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Uptake of Influenza Vaccination and Missed Opportunities Among Adults with High-Risk Conditions, United States, 2013

  • Peng-jun Lu
    Correspondence
    Requests for reprints should be addressed to Peng-jun Lu, MD, PhD, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, 1600 Clifton Road, NE, Mail Stop E-62, Atlanta, GA 30333.
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Ga
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  • Alissa O'Halloran
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Ga

    Leidos Inc, Atlanta, Ga
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  • Helen Ding
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Ga

    Eagle Medical Services LLC, San Antonio, Tex
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  • Anup Srivastav
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Ga

    Leidos Inc, Atlanta, Ga
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  • Walter W. Williams
    Affiliations
    Immunization Services Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, Ga
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Published:November 06, 2015DOI:https://doi.org/10.1016/j.amjmed.2015.10.031

      Abstract

      Background

      Since 1960, the Advisory Committee on Immunization Practices has recommended influenza vaccination for adults with certain high-risk conditions because of increased risk for complications from influenza infection. We assessed national influenza vaccination among persons ages 18-64 years with high-risk conditions.

      Methods

      We analyzed data from the 2012 and 2013 National Health Interview Survey. The Kaplan-Meier survival analysis procedure was used to estimate the cumulative proportion of influenza vaccination among adults ages 18-64 years with high-risk conditions. Potential missed opportunities for influenza vaccination were also evaluated. Multivariable logistic regression and predictive marginal analyses were conducted to identify factors independently associated with vaccination.

      Results

      Overall, 39.9 million adults ages 18-64 years (18.9%) had at least one high-risk condition. For adults ages 18-64 years with high-risk conditions, overall influenza vaccination coverage was 49.5%. Coverage among adults 50-64 years of age was significantly higher compared with those ages 18-49 years (59.3% vs 39.0%; P <.05). Among adults ages 18-64 years, coverage was 46.2% for those with chronic lung diseases, 50.5% for those with heart disease, 58.0% for those with diabetes, 62.5% for those with renal disease, and 56.4% for those with cancer. Overall, 90.1% reported at least one visit to a health care setting where vaccination could have been provided. Among adults ages 18-64 years with high-risk conditions, older age, being female, Hispanic ethnicity or Asian race, having one or more physician visits, a regular physician for health care, health insurance, and having ever received pneumococcal vaccination were independently associated with a higher likelihood of influenza vaccination. Being widowed/divorced/separated or never married and not being employed were independently associated with a lower likelihood of influenza vaccination.

      Conclusions

      Influenza vaccination coverage varies substantially by age and high-risk conditions but remains low. Approximately 50% of those with high-risk conditions remain unvaccinated. Health care providers should ensure they routinely assess influenza vaccination status, and recommend and offer vaccines to those with high-risk conditions.

      Keywords

      Clinical Significance
      • In 2012-2013, an estimated 40 million adults 18-64 years of age had medical conditions, but only about 50% had received the vaccine.
      • Overall, 90.1% of unvaccinated individuals reported at least one visit to a health care setting where vaccination could have been provided.
      • Healthcare providers should consider each office or emergency department visit a potential opportunity to vaccinate patients with high-risk conditions.
      Persons with underlying high-risk conditions such as asthma, bronchitis, emphysema, chronic obstructive pulmonary disease, heart disease, renal disease, diabetes, and cancer are known to be at substantially increased risk for serious complications from influenza.
      • Grohskopf L.A.
      • Olsen S.J.
      • Sokolow L.Z.
      • et al.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP)—United States, 2014-15 influenza season.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of seasonal influenza with vaccines. Recommendations of the Advisory Committee on Immunization Practices (ACIP)—United States, 2013-2014.
      • Monto A.S.
      Epidemiology of influenza.
      Vaccination of persons with high-risk conditions is a key public health strategy in preventing influenza-related morbidity and mortality in the US.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of seasonal influenza with vaccines. Recommendations of the Advisory Committee on Immunization Practices (ACIP)—United States, 2013-2014.
      Optimal use of vaccination strategies not only can reduce influenza-related morbidity and mortality, but also can minimize missed work days due to illness.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of seasonal influenza with vaccines. Recommendations of the Advisory Committee on Immunization Practices (ACIP)—United States, 2013-2014.
      Persons with high-risk conditions were recommended for annual influenza vaccination by the Public Health Service as early as 1960.
      • Burney L.E.
      Influenza immunization: statement.
      Before 2010, the Advisory Committee on Immunization Practices (ACIP) recommended yearly vaccination for adults ages ≥50 years and adults 18-49 years with high-risk conditions.
      • Fiore A.E.
      • Uyeki T.M.
      • Broder K.
      • et al.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices.
      Since the 2010-2011 season, the ACIP has recommended annual influenza vaccination for all adults.
      • Grohskopf L.A.
      • Olsen S.J.
      • Sokolow L.Z.
      • et al.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP)—United States, 2014-15 influenza season.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of seasonal influenza with vaccines. Recommendations of the Advisory Committee on Immunization Practices (ACIP)—United States, 2013-2014.
      • Fiore A.E.
      • Uyeki T.M.
      • Broder K.
      • et al.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices.
      Healthy People 2020 provides a comprehensive set of 10-year, national goals and objectives for improving the health of all Americans.

      US Department of Health and Human Services. Immunization and infectious diseases. Available at: http://www.healthypeople.gov/2020/topics-objectives/topic/immunization-and-infectious-diseases/objectives. Accessed March 11, 2015.

      Before Healthy People 2020 of influenza vaccination objectives were consolidated following the ACIP recommendation for universal vaccination of adults, the annual influenza vaccination target for adults 18-64 years with high-risk conditions was 90%.

      US Department of Health and Human Services. Immunization and infectious diseases. Available at: http://www.healthypeople.gov/2020/topics-objectives/topic/immunization-and-infectious-diseases/objectives. Accessed March 11, 2015.

      The current revised vaccination target for all adults ≥18 years of age is 70%

      US Department of Health and Human Services. Immunization and infectious diseases. Available at: http://www.healthypeople.gov/2020/topics-objectives/topic/immunization-and-infectious-diseases/objectives. Accessed March 11, 2015.

      ; however, ACIP continues to emphasize that persons with high-risk conditions should be a focus of vaccination efforts.
      • Fiore A.E.
      • Uyeki T.M.
      • Broder K.
      • et al.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices.
      Despite the long-standing ACIP recommendations, vaccination levels among persons with medical conditions that increase risk for complications from influenza have remained suboptimal.

      Centers for Disease Control and Prevention (CDC). Flu vaccination coverage, United States, 2012-13 influenza season. Available at: http://www.cdc.gov/flu/fluvaxview/coverage-1213estimates.htm. Accessed March 11, 2015.

      • Egede L.E.
      • Zheng D.
      Racial/ethnic differences in influenza vaccination coverage in high-risk adults.
      • Singleton J.A.
      • Wortley P.M.
      • Lu P.J.
      Influenza vaccination of persons with cardiovascular disease in the United States.
      Centers for Disease Control and Prevention (CDC)
      Interim results: state-specific seasonal influenza vaccination coverage—United States, August 2009-January 2010.
      • Lu P.J.
      • Singleton J.A.
      • Euler G.L.
      • Williams W.W.
      • Bridges C.B.
      Seasonal influenza vaccination of adult populations, U.S., 2005-2011.
      To evaluate the impact of the current adult influenza vaccination program in the US for persons with high-risk conditions, we assessed national influenza vaccination coverage and potential missed opportunities for vaccination among adults 18-64 years with underlying high-risk conditions using data from the National Health Interview Survey (NHIS). We also evaluated demographic and access-to-care factors associated with receipt of influenza vaccination to identify potential strategies to improve vaccination coverage.

      Methods

      We analyzed data from the 2012 and 2013 NHIS. NHIS is a probability-based annual household survey conducted by the National Center for Health Statistics of the Centers for Disease Control and Prevention.

      Centers for Disease Control and Prevention (CDC). 2012 National Health Interview Survey (NHIS): public use data release. Available at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/2012/srvydesc.pdf. Accessed March 11, 2015.

      Centers for Disease Control and Prevention (CDC). 2013 National Health Interview Survey (NHIS): public use data release. Available at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/2013/srvydesc.pdf. Accessed March 11, 2015.

      The survey has 4 main modules: the household composition section, family core, sample adult core, and sample child core. In the sample adult core, one adult per sampled family was randomly selected and asked to complete the sample adult questionnaire, including questions about receipt of influenza vaccination. In 2012 and 2013, the final response rates for the sample adult core were 61.2% for both years.

      Centers for Disease Control and Prevention (CDC). 2012 National Health Interview Survey (NHIS): public use data release. Available at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/2012/srvydesc.pdf. Accessed March 11, 2015.

      Centers for Disease Control and Prevention (CDC). 2013 National Health Interview Survey (NHIS): public use data release. Available at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/2013/srvydesc.pdf. Accessed March 11, 2015.

      We defined high-risk persons as individuals who self-reported one or more of the following: ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack or other heart condition; being diagnosed with cancer in the past 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; during the past 12 months, being told by a physician they have chronic bronchitis or weak or failing kidneys; or reporting an asthma episode or attack in the past 12 months. Poverty status was defined as a total family income of <$23,492 and <$23,624 for a family of 4 for 2012 and 2013, respectively, using poverty thresholds published by the US Census Bureau.

      U.S. Census Bureau. Poverty thresholds. Available at: http://www.census.gov/hhes/www/poverty/data/threshld/. Accessed on May 4, 2015.

      SUDAAN (software for the statistical analysis of correlated data, version 10.01; Research Triangle Institute, Research Triangle Park, NC) was used to calculate point estimates and 95% confidence intervals. In bivariate analyses, we assessed influenza vaccination among adults 18-64 years of age with high-risk conditions stratified by demographic and access-to-care variables. Chi-squared and t tests were used to determine differences between groups with statistical significance at P <.05. To better assess seasonal influenza vaccination coverage, we reported coverage restricted to individuals interviewed during August 2012 through June 2013, and vaccinated during July 2012 through May 2013 using the Kaplan-Meier survival analysis procedure. Multivariable logistic regression and predictive marginal models were used to generate adjusted prevalence ratios and identify variables independently associated with reported receipt of influenza vaccination in the past 12 months.
      • Korn E.L.
      • Graubard B.I.
      Predictive margins (direct standardization).
      • Nadel M.R.
      • Shapiro J.A.
      • Klabunde C.N.
      • et al.
      A national survey of primary care physicians' methods for screening for fecal occult blood.
      All variables used in the bivariate analysis were included in the full multivariable model. To assess potential missed opportunities for influenza vaccination among adults with high-risk conditions, we calculated the proportions of persons who reported not receiving influenza vaccination in the 2012-2013 influenza season by selected health care access characteristics.

      Results

      Table 1 shows the baseline demographic characteristics of the study population.
      Table 1Characteristics of Participants 18-64 Years with High-risk Conditions
      High-risk definition: adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      in the United States, by Demographic and Access-to-care Characteristics—NHIS 2012-2013
      Includes respondents interviewed from August 2012 through June 2013.
      CharacteristicsAge Group
      18-64 y18-49 y50-64 y
      Sample%Sample%Sample%
      Total4853100.0226448.5258951.5
      Sex
       Male207446.887943.0119550.4
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       Female277953.2138557.0139449.6
      Race/ethnicity
       Non-Hispanic white292868.2131665.8161270.3
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       Non-Hispanic black85113.337213.447913.2
       Hispanic74612.440914.533710.4
       Asian1633.2743.0893.4
       Other1652.9933.3722.6
      Marital status
       Married199953.285846.4114159.5
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       Widowed/divorced/separated140820.243814.297025.7
       Never married143126.796339.446814.7
      Education
       <High school85116.237016.048116.4
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       High school graduate131427.056025.375428.6
       Some college+267456.8133258.7134254.9
      Employment status
       Employed261156.2144764.0116448.9
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       Not employed3136.32038.71104.0
       Not in work force192737.561427.3131347.2
      Poverty level
       At or above poverty331279.7150976.9180382.4
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       Below poverty117820.361323.156517.6
      US born status
       US born416587.2192887.0223787.3
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       Born outside US, in US ≤10 y861.7682.9180.7
       Born outside US, in US >10 y59311.126410.132912.0
      Region of residence
       Northeast77917.037217.540716.5
       Midwest98322.845521.852823.8
       South191439.087138.8104339.2
       West117721.256621.961120.5
      Physician contacts within past year
       None4439.426811.81757.2
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       146510.026012.32057.8
       2-3106723.352223.154523.5
       4-9155032.766229.888835.5
       >10122324.651123.071226.0
      Hospitalization within past year
       Yes89317.134815.154519.0
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       No395582.9191584.9204081.0
      Regular physician
       Yes435190.4193786.4241494.1
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       No4609.631113.61495.9
      Health insurance
       With health insurance396682.8176279.3220486.0
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       Without health insurance86917.249420.737514.0
      Ever received pneumococcal vaccination
       Yes142230.543821.398439.0
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
       No319669.5170678.7149061.0
      NHIS = National Health Interview Survey.
      High-risk definition: adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      Includes respondents interviewed from August 2012 through June 2013.
      P <.05 by chi-square test (comparing persons 18-49 years with 50-64 years).
      The overall influenza vaccination coverage for the 2012-2013 season among adults ages 18-64 years with high-risk conditions was 49.5%. Vaccination coverage for the 2012-2013 season among adults with high-risk conditions was significantly lower among adults ages 18-49 years at 39.0% compared with 59.3% for adults ages 50-64 years (Table 2). Vaccination coverage for adults 18-64 years of age with high-risk conditions was 49.0% for non-Hispanic whites, 45.8% for non-Hispanic blacks, 49.4% for Hispanics, 65.9% for Asians, and 60.6% for those reporting other race (Table 2). Coverage was significantly higher among Asians, compared with non-Hispanic whites (P <.05) (Table 2). Coverage for adults 18-64 years of age with high-risk conditions was significantly higher among adults with at least some college education, who were employed and living at or above poverty level (Table 2) (P <.05). Additionally, coverage was significantly lower among adults who were never married, and those who were born outside the US and were in the US <10 years (Table 2) (P <.05).
      Table 2Influenza Vaccination Coverage
      Participants vaccinated July 2012-May 2013 and interviewed August 2012-June 2013.
      Among Adults Aged 18-64 Years with High-risk Conditions
      High-risk definition: adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      in the United States, by Demographic and Access-to-care Characteristics—NHIS 2012-2013
      CharacteristicsAge Group
      18-64 y18-49 y50-64 y
      %(95% CI)%(95% CI)%(95% CI)
      Total49.5(47.2-51.9)39.0(35.8-42.4)59.3(55.8-62.8)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Sex
       Male
      Reference level.
      46.9(43.2-50.8)32.8(27.8-38.3)58.0(53.0-63.1)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Female51.8(48.7-55.0)43.6(39.0-48.5)
      P <.05 by t test comparing against the reference group.
      60.7(56.4-65.0)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Race/ethnicity
       Non-Hispanic white
      Reference level.
      49.0(46.1-52.0)36.6(32.7-40.7)59.6(55.3-63.8)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Non-Hispanic black45.8(39.4-52.7)40.5(32.4-49.8)50.8(42.0-60.3)
       Hispanic49.4(43.6-55.4)39.7(32.0-48.5)62.6(53.7-71.4)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Asian65.9(52.2-79.2)
      P <.05 by t test comparing against the reference group.
      61.9(39.8-84.0)
      P <.05 by t test comparing against the reference group.
      70.5(56.1-83.6)
       Other60.6(48.2-73.2)56.2(40.6-73.0)
      P <.05 by t test comparing against the reference group.
      68.0(48.9-85.6)
      Marital status
       Married
      Reference level.
      53.5(50.0-57.1)43.8(38.7-49.2)60.6(55.5-65.7)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Widowed/divorced/separated49.6(45.3-54.1)36.2(29.0-44.5)56.1(50.8-61.7)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Never married42.1(37.7-46.8)
      P <.05 by t test comparing against the reference group.
      34.9(30.2-40.1)
      P <.05 by t test comparing against the reference group.
      59.3(51.4-67.4)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Education
       <High school
      Reference level.
      45.3(39.4-51.7)34.5(26.5-44.1)55.5(46.7-64.7)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       High school graduate43.7(39.2-48.6)33.2(26.3-41.3)52.2(46.4-58.2)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Some college+53.6(50.5-56.6)
      P <.05 by t test comparing against the reference group.
      42.8(39.0-46.9)64.2(59.5-68.9)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Employment status
       Employed
      Reference level.
      48.2(45.2-51.3)40.6(36.9-44.6)57.2(52.3-62.1)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Not employed31.4(23.9-40.7)
      P <.05 by t test comparing against the reference group.
      26.0(17.2-38.0)
      P <.05 by t test comparing against the reference group.
      44.4(29.2-63.2)
       Not in work force54.9(51.3-58.6)
      P <.05 by t test comparing against the reference group.
      40.1(33.6-47.3)63.2(58.6-67.7)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Poverty level
       At or above poverty50.4(47.7-53.2)
      P <.05 by t test comparing against the reference group.
      40.1(36.3-44.1)59.7(55.6-63.8)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Below poverty
      Reference level.
      43.6(38.4-49.2)36.2(29.4-44.0)52.8(45.4-60.5)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      US born status
       US born
      Reference level.
      49.4(46.8-52.0)39.1(35.6-42.7)58.9(55.0-62.8)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Born outside US, in US ≤10 y31.1(17.4-51.7)
      P <.05 by t test comparing against the reference group.
      Estimate may not be reliable due to relative standard error >0.3 or sample size <30.
      Estimate may not be reliable due to relative standard error >0.3 or sample size <30.
      68.1(40.3-92.0)
       Born outside US, in US >10 y54.0(47.6-60.6)44.7(35.7-54.8)61.0(51.6-70.6)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Region of residence
       Northeast
      Reference level.
      51.5(45.1-58.2)39.5(31.6-48.4)63.6(55.9-71.2)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       Midwest49.8(44.9-54.9)41.4(34.4-49.3)56.7(48.3-65.5)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       South48.0(44.6-51.4)36.8(32.0-42.2)58.0(52.9-63.2)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       West50.6(45.9-55.6)40.7(34.3-47.8)60.6(52.9-68.3)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Physician contacts within past year
       None
      Reference level.
      18.3(12.8-25.8)14.5(8.6-23.9)23.3(14.8-35.7)
       136.1(29.0-44.2)
      P <.05 by t test comparing against the reference group.
      27.4(19.6-37.6)
      P <.05 by t test comparing against the reference group.
      47.0(36.2-59.3)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      P <.05 by t test comparing against the reference group.
       2-347.7(43.0-52.7)
      P <.05 by t test comparing against the reference group.
      38.0(31.1-45.8)
      P <.05 by t test comparing against the reference group.
      57.5(50.2-65.0)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      P <.05 by t test comparing against the reference group.
       4-955.9(51.6-60.3)
      P <.05 by t test comparing against the reference group.
      46.7(40.6-53.3)
      P <.05 by t test comparing against the reference group.
      63.2(57.4-69.1)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      P <.05 by t test comparing against the reference group.
       >1060.4(56.0-64.8)
      P <.05 by t test comparing against the reference group.
      48.7(41.9-56.0)
      P <.05 by t test comparing against the reference group.
      69.8(64.2-75.1)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      P <.05 by t test comparing against the reference group.
      Hospitalization within past year
       Yes58.7(53.3-64.3)
      P <.05 by t test comparing against the reference group.
      51.6(43.0-60.9)
      P <.05 by t test comparing against the reference group.
      64.6(57.4-71.7)
      P <.05 by t test comparing 18-49 years with 50-64 years.
       No
      Reference level.
      47.7(45.1-50.4)36.8(33.2-40.7)58.0(54.2-61.9)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Regular physician
       Yes53.2(50.7-55.7)
      P <.05 by t test comparing against the reference group.
      42.6(39.0-46.4)
      P <.05 by t test comparing against the reference group.
      62.1(58.5-65.7)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      P <.05 by t test comparing against the reference group.
       No
      Reference level.
      15.1(10.5-21.5)16.5(11.1-24.1)12.2(6.8-21.5)
      Health insurance
       With health insurance55.1(52.5-57.7)
      P <.05 by t test comparing against the reference group.
      44.5(40.7-48.5)
      P <.05 by t test comparing against the reference group.
      64.1(60.5-67.7)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      P <.05 by t test comparing against the reference group.
       Without health insurance
      Reference level.
      23.9(19.9-28.6)19.4(14.3-26.2)30.0(23.1-38.4)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      Ever received pneumococcal vaccination
       Yes73.4(69.6-77.0)
      P <.05 by t test comparing against the reference group.
      63.7(56.3-71.0)
      P <.05 by t test comparing against the reference group.
      78.2(73.9-82.3)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      P <.05 by t test comparing against the reference group.
       No
      Reference level.
      38.7(36.0-41.6)31.6(28.0-35.4)46.9(42.3-51.8)
      P <.05 by t test comparing 18-49 years with 50-64 years.
      CI = confidence interval; NHIS = National Health Interview Survey.
      Participants vaccinated July 2012-May 2013 and interviewed August 2012-June 2013.
      High-risk definition: adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      P <.05 by t test comparing 18-49 years with 50-64 years.
      § Reference level.
      P <.05 by t test comparing against the reference group.
      Estimate may not be reliable due to relative standard error >0.3 or sample size <30.
      Among adults 18-64 years of age with high-risk conditions, vaccination coverage was higher for those who had any physician contacts during the past year, compared with those with none, and increased with higher numbers of physician contacts. There was almost a 40 percentage-point difference in proportion vaccinated between those who had no physician contacts and those who had 10 or more physician contacts in the past year (Table 2). Persons who had been hospitalized in the past year were significantly more likely to have received influenza vaccination than those who were not. There was a 38 percentage-point difference in vaccination coverage between those who had a regular physician for health care and those who did not have one. Coverage was significantly higher (P <.05) among adults with health insurance (55.1%) compared with those without health insurance (23.9%), and among adults who had ever received pneumococcal vaccination (73.4%) compared with those who had not (38.7%) (P <.05 for both comparisons) (Table 2). Vaccination coverage was significantly higher among adults ages 50-64 years compared with adults ages 18-49 years across most sociodemographic and access-to-care characteristics (Table 2).
      In multivariable analysis, among adults ages 18-64 years with high-risk conditions: older age, being female, Hispanic ethnicity or Asian race, having one or more physician visits, a regular physician for health care, health insurance, and having ever received pneumococcal vaccination were independently associated with a higher likelihood of influenza vaccination. Being widowed/divorced/separated and not being employed were independently associated with a lower likelihood of influenza vaccination (Table 3). Among adults 18-49 years of age with high-risk conditions, characteristics independently associated with a higher likelihood of vaccination were similar to those for subjects 18-64 years of age. Never having been married and not being employed were independently associated with a lower likelihood of vaccination (Table 3). Among adults 50-64 years of age with high-risk conditions, Hispanic ethnicity, having 2 or more physician visits, a regular physician for health care, health insurance, and having ever received pneumococcal vaccination were independently associated with a higher likelihood of vaccination (Table 3).
      Table 3Multivariable Logistic Regression and Predictive Marginal Analysis
      Participants interviewed August 2012-June 2013 and vaccinated within the past 12 months from date of interview.
      of Influenza Vaccination Among Adults 18-64 Years with High-risk Conditions
      High-risk definition: adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      in the United States, by Demographic and Access-to-care Characteristics—NHIS 2012-2013
      CharacteristicsAge Group
      18-64 y18-49 y50-64 y
      PR (95% CI)PR (95% CI)PR (95% CI)
      Age
       18-49 yReferenceNANA
       50-64 y1.27 (1.17-1.39)
      P <.05 compared with the reference level.
      NANA
      Sex
       MaleReferenceReferenceReference
       Female1.12 (1.03-1.21)
      P <.05 compared with the reference level.
      1.24 (1.07-1.44)
      P <.05 compared with the reference level.
      1.05 (0.96-1.15)
      Race/ethnicity
       Non-Hispanic whiteReferenceReferenceReference
       Non-Hispanic black0.94 (0.83-1.06)1.00 (0.82-1.22)0.90 (0.78-1.05)
       Hispanic1.21 (1.07-1.37)
      P <.05 compared with the reference level.
      1.26 (1.03-1.54)
      P <.05 compared with the reference level.
      1.19 (1.03-1.38)
      P <.05 compared with the reference level.
       Asian1.33 (1.10-1.63)
      P <.05 compared with the reference level.
      1.64 (1.25-2.17)
      P <.05 compared with the reference level.
      1.16 (0.90-1.51)
       Other1.21 (0.98-1.50)1.39 (1.03-1.87)1.10 (0.83-1.45)
      Marital status
       MarriedReferenceReferenceReference
       Widowed/divorced/separated0.89 (0.81-0.97)
      P <.05 compared with the reference level.
      0.85 (0.70-1.03)0.92 (0.84-1.01)
       Never married0.93 (0.85-1.02)0.86 (0.74-1.00)
      P <.05 compared with the reference level.
      1.01 (0.89-1.14)
      Education
       <High schoolReferenceReferenceReference
       High school graduate0.95 (0.83-1.10)0.92 (0.71-1.19)0.98 (0.84-1.15)
       Some college+1.10 (0.98-1.25)1.05 (0.86-1.29)1.13 (0.98-1.30)
      Employment status
       EmployedReferenceReferenceReference
       Not employed0.81 (0.68-0.97)
      P <.05 compared with the reference level.
      0.77 (0.58-1.02)
      P <.05 compared with the reference level.
      0.84 (0.65-1.07)
       Not in work force0.95 (0.87-1.04)0.93 (0.78-1.12)0.96 (0.87-1.06)
      Poverty level
       At or above poverty1.08 (0.97-1.21)1.12 (0.91-1.37)1.05 (0.93-1.20)
       Below povertyReferenceReferenceReference
      US born status
       US bornReferenceReferenceReference
       Born outside US-in US ≤10 y1.02 (0.79-1.33)0.96 (0.66-1.40)1.01 (0.60-1.72)
       Born outside US-in US >10 y1.03 (0.90-1.17)0.99 (0.78-1.25)1.05 (0.88-1.24)
      Region of residence
       NortheastReferenceReferenceReference
       Midwest1.01 (0.90-1.15)1.02 (0.83-1.26)1.02 (0.88-1.18)
       South0.98 (0.88-1.10)0.98 (0.83-1.17)1.00 (0.87-1.14)
       West0.99 (0.88-1.11)1.02 (0.84-1.25)0.97 (0.83-1.14)
      Physician contacts within past year
       NoneReferenceReferenceReference
       11.27 (1.00-1.63)
      P <.05 compared with the reference level.
      1.32 (0.92-1.90)1.25 (0.92-1.71)
       2-31.47 (1.18-1.83)
      P <.05 compared with the reference level.
      1.53 (1.10-2.13)
      P <.05 compared with the reference level.
      1.41 (1.05-1.90)
      P <.05 compared with the reference level.
       4-91.48 (1.18-1.85)
      P <.05 compared with the reference level.
      1.53 (1.11-2.10)
      P <.05 compared with the reference level.
      1.43 (1.05-1.95)
      P <.05 compared with the reference level.
       >101.54 (1.22-1.93)
      P <.05 compared with the reference level.
      1.53 (1.07-2.18)
      P <.05 compared with the reference level.
      1.52 (1.12-2.06)
      P <.05 compared with the reference level.
      Hospitalization within past year
       Yes1.05 (0.94-1.17)1.11 (0.91-1.37)1.01 (0.90-1.13)
       NoReferenceReferenceReference
      Regular physician
       Yes1.68 (1.33-2.11)
      P <.05 compared with the reference level.
      1.58 (1.17-2.12)
      P <.05 compared with the reference level.
      2.22 (1.44-3.43)
      P <.05 compared with the reference level.
       NoReferenceReferenceReference
      Health insurance
       With health insurance1.41 (1.21-1.64)
      P <.05 compared with the reference level.
      1.52 (1.21-1.92)
      P <.05 compared with the reference level.
      1.34 (1.10-1.64)
      P <.05 compared with the reference level.
       Without health insuranceReferenceReferenceReference
      Ever received pneumococcal vaccination
       Yes1.76 (1.63-1.89)
      P <.05 compared with the reference level.
      2.06 (1.80-2.36)
      P <.05 compared with the reference level.
      1.58 (1.44-1.72)
      P <.05 compared with the reference level.
       NoReferenceReferenceReference
      CI = confidence interval; NHIS = National Health Interview Survey.
      Participants interviewed August 2012-June 2013 and vaccinated within the past 12 months from date of interview.
      High-risk definition: adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      P <.05 compared with the reference level.
      Among adults 18-64 years of age, influenza vaccination coverage in the 2012-2013 season was 49.5% among those with at least one high-risk condition, 59.5% among those with at least 2 high-risk conditions, 46.2% among those with lung disease, 50.5% among those with heart disease, 58.0% among those with diabetes, 62.5% among those with renal disease, and 56.4% among those with cancer (Table 4). Additionally, most condition-specific vaccination coverage was significantly higher among persons ages 50-64 years compared with those ages 18-49 years (Table 4).
      Table 4Prevalence of Specific Conditions and Vaccination Coverage
      Participants vaccinated July 2012-May 2013 and interviewed August 2012-June 2013.
      Among Adults 18-64 Years, United States, NHIS 2012-2013
      Persons 18-64 yPersons 18-49 yPersons 50-64 y
      Prevalence of ConditionsPopulation Estimates (Weighted Sample Size)Vaccination CoveragePrevalence of ConditionsPopulation Estimates (Weighted Sample Size)Vaccination CoveragePrevalence of ConditionsPopulation Estimates (Weighted Sample Size)Vaccination Coverage
      % (95% CI)In Millions% (95% CI)% (%95 CI)In Millions% (95% CI)% (95% CI)In Millions% (95% CI)
      Lung diseases
      Persons reported one or more of the following: being told by a physician they had chronic bronchitis in the past 12 months; being told they had an asthma attack in the past 12 months; ever being told they had emphysema; ever being told they had chronic obstructive pulmonary disease.
      7.7 (7.3-8.2)16.346.2 (42.5-50.1)6.3 (5.9-6.8)9.137.6 (32.6-43.2)10.8 (9.9-11.6)7.256.6 (51.3-62.0)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
       Active asthma3.9 (3.6-4.3)8.244.0 (39.1-49.3)4.0 (3.6-4.4)5.734.8 (29.4-41.0)3.8 (3.4-4.4)2.664.0 (55.1-72.9)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
       Bronchitis3.5 (3.2-3.8)7.350.0 (44.7-55.7)2.6 (2.3-3.0)3.842.9 (35.2-51.6)5.3 (4.7-5.9)3.557.1 (48.8-65.7)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
       Emphysema1.1 (0.9-1.3)2.351.0 (40.4-62.5)0.5 (0.4-0.6)0.749.3 (28.3-74.9)2.4 (2.0-2.8)1.652.1 (41.5-63.5)
       COPD1.8 (1.6-2.1)3.955.2 (47.7-63.0)0.8 (0.6-0.9)1.145.6 (30.2-64.4)4.2 (3.7-4.8)2.859.3 (51.7-67.1)
      Heart disease
      Persons reporting one or more of the following heart conditions: coronary heart disease, angina, heart attack, or other heart condition.
      7.5 (7.1-8.0)15.950.5 (46.8-54.3)4.6 (4.2-5.0)6.738.1 (33.0-43.6)13.8 (12.8-14.8)9.259.5 (54.4-64.7)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
      Diabetes6.7 (6.3-7.2)14.258.0 (53.9-62.1)3.4 (3.1-3.8)4.945.1 (38.4-52.3)13.8 (12.9-14.9)9.265.0 (59.9-70.1)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
      Renal disease1.2 (1.1-1.4)2.662.5 (53.6-71.5)0.8 (0.7-1.0)1.250.2 (37.3-64.6)2.1 (1.7-2.5)1.474.8 (65.2-83.4)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
      Cancer0.9 (0.8-1.1)1.956.4 (45.2-68.2)0.5 (0.4-0.7)0.749.9 (32.5-70.5)1.7 (1.4-2.1)1.160.5 (47.1-74.2)
      ≥1 high-risk condition
      Adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      18.9 (18.3-19.6)39.949.5 (47.2-51.9)13.4 (12.8-14.1)19.339.0 (35.8-42.4)30.8 (29.6-32.1)20.559.3 (55.8-62.8)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
      ≥2 high-risk condition
      Adults categorized as at high risk for influenza-related complications self-reported 2 or more of the following: lung disease, heart disease, diabetes, renal disease, or cancers.
      4.0 (3.7-4.4)8.559.5 (54.3-64.8)1.9 (1.7-2.2)2.849.0 (39.3-59.7)8.6 (7.8-9.5)5.764.7 (58.5-70.9)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
      No high-risk conditions81.1 (80.4-81.7)170.532.9 (31.6-34.2)86.6 (85.9-87.2)124.529.2 (27.8-30.7)69.2 (67.9-70.4)46.042.8 (40.5-45.2)
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
      CI = confidence interval; COPD = chronic obstructive pulmonary disease; NHIS = National Health Interview Survey.
      Participants vaccinated July 2012-May 2013 and interviewed August 2012-June 2013.
      Persons reported one or more of the following: being told by a physician they had chronic bronchitis in the past 12 months; being told they had an asthma attack in the past 12 months; ever being told they had emphysema; ever being told they had chronic obstructive pulmonary disease.
      P <.05 by t test for comparisons of vaccination coverage between persons ages 18-49 years and persons 50-64 years.
      § Persons reporting one or more of the following heart conditions: coronary heart disease, angina, heart attack, or other heart condition.
      Adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      Adults categorized as at high risk for influenza-related complications self-reported 2 or more of the following: lung disease, heart disease, diabetes, renal disease, or cancers.
      Potential missed opportunities for influenza vaccination also were evaluated. Among adults 18-64 years of age with at least one high-risk condition who reported not receiving influenza vaccination in the 2012-2013 season, 87.3% had one or more physician contacts in the last 12 months, 15.2% were hospitalized in past year, and 31.7% had visited an emergency department (ED). Overall, 90.1% reported at least one visit to a health care setting where vaccination could have been provided. Among persons reporting ≥2 ED visits, the proportion was significantly higher among non-Hispanic blacks (25.2%). Among those with at least one potential missed opportunity, Hispanics had the lowest proportion (85.2%) (Table 5).
      Table 5Select Health Care Access Characteristics Among Persons Ages 18-64 Years with High-risk Conditions
      High-risk definition: adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      Who Reported Not Receiving Influenza Vaccination in the 2012-2013 Season
      Includes August 2012-June 2013 interviews; estimates the proportion of adults with high-risk conditions who had not received influenza vaccination from July 2012 through May 2013.
      and Potential Missed Opportunities for Influenza Vaccination – NHIS 2012-2013
      CharacteristicSample, nTotal % (95% CI)Non-Hispanic white % (95% CI)Non-Hispanic black % (95% CI)Hispanic % (95% CI)
      Doctor visit
       No visit37912.7 (11.2-14.3)12.5 (10.6-14.6)10.2 (7.1-14.3)17.0 (13.3-21.5)
       1 visit36411.5 (10.1-13.2)10.6 (8.9-12.5)14.3 (10.4-19.3)14.1 (10.8-18.2)
       2-3 visits73523.9 (22.1-25.8)23.7 (21.3-26.2)22.9 (18.8-27.6)23.2 (19.0-28.0)
       4-9 visits99230.5 (28.5-32.5)30.6 (28.0-33.3)33.5 (28.6-38.8)27.2 (22.8-32.0)
       10+ visits72521.4 (19.6-23.4)22.7 (20.3-25.4)19.2 (15.6-23.4)18.5 (15.0-22.7)
      Hospitalization in past year
       Yes50915.2 (13.7-16.8)14.8 (13.1-16.8)20.3 (15.8-25.5)12.7 (9.9-16.2)
       No269384.8 (83.2-86.3)85.2 (83.2-86.9)79.7 (74.5-84.2)87.3 (83.8-90.1)
      Emergency Department (ED) visit
       0213768.3 (66.1-70.4)69.6 (66.9-72.1)56.6 (51.2-61.9)
      Indicates P <.05 (chi-squared test for association between race/ethnicity, non-Hispanic white is the reference group).
      70.7 (65.8-75.2)
       151516.2 (14.6-18.0)16.6 (14.6-18.9)18.2 (14.3-22.8)13.9 (10.5-18.1)
       2+54915.5 (13.9-17.3)13.8 (12.0-15.9)25.2 (21.1-29.9)
      Indicates P <.05 (chi-squared test for association between race/ethnicity, non-Hispanic white is the reference group).
      15.4 (12.2-19.3)
      At least one possible missed opportunity
       Yes
      Indicates persons reported one more of the following: had at least one doctor visit, hospitalized in the past year, had at least one ED visit.
      290290.1 (88.7-91.3)90.2 (88.3-91.8)93.4 (90.4-95.5)85.2 (80.8-88.7)
      Indicates P <.05 (chi-squared test for association between race/ethnicity, non-Hispanic white is the reference group).
       No2969.9 (8.7-11.3)9.8 (8.2-11.7)6.6 (4.5-9.6)14.8 (11.3-19.2)
      CI = confidence interval; NHIS = National Health Interview Survey.
      High-risk definition: adults categorized as at high risk for influenza-related complications self-reported 1 or more of the following: 1) ever being told by a physician they had diabetes, emphysema, chronic obstructive pulmonary disease, coronary heart disease, angina, heart attack, or other heart condition; 2) having a diagnosis of cancer during the preceding 12 months (excluding nonmelanoma skin cancer) or ever being told by a physician they have lymphoma, leukemia, or blood cancer; 3) being told by a physician they have chronic bronchitis or weak or failing kidneys; or 4) reporting an asthma episode or attack during the preceding 12 months.
      Includes August 2012-June 2013 interviews; estimates the proportion of adults with high-risk conditions who had not received influenza vaccination from July 2012 through May 2013.
      Indicates P <.05 (chi-squared test for association between race/ethnicity, non-Hispanic white is the reference group).
      § Indicates persons reported one more of the following: had at least one doctor visit, hospitalized in the past year, had at least one ED visit.

      Discussion

      Findings from this study demonstrate that among adults 18-64 years of age with high-risk conditions, influenza vaccination coverage was low overall as well as among those with multiple high-risk conditions. During the 2012-2013 season, about 40%-60% of adults ages 18-64 years at increased risk for influenza were unvaccinated against influenza. Vaccination coverage remained well below the previous Healthy People 2020 target of 90% for all the influenza high-risk groups studied and below the current target of 70% set for all adults.

      US Department of Health and Human Services. Immunization and infectious diseases. Available at: http://www.healthypeople.gov/2020/topics-objectives/topic/immunization-and-infectious-diseases/objectives. Accessed March 11, 2015.

      Factors associated with lower influenza vaccination coverage among adults with high-risk conditions have been described in other studies and might include: lack of a preexisting relationship of state immunization programs with providers who serve adults at high risk; difficulty in implementing a risk-condition-based vaccination recommendation; persons with underlying health conditions not considering themselves as high risk limiting the effectiveness of targeted messages; and historically low seasonal influenza vaccination coverage in this population.
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      • Parrott M.A.
      The Diabetes Quality Improvement Project: moving science into health policy to gain an edge on the diabetes epidemic.

      National Asthma Education and Prevention Program. Draft needs assessment report for potential update of the expert panel report-3(2007): guidelines for the diagnosis and management of asthma, April 2014. Bethesda, MD: National Institutes of Health, National Heart, Lung, and Blood Institute. Available at: https://www.nhlbi.nih.gov/health-pro/resources/lung/nhlbac-asthma-report. Accessed March 15, 2015.

      • Davis M.M.
      • Taubert K.
      • Benin A.L.
      • et al.
      Influenza vaccination as secondary prevention for cardiovascular disease: a science advisory from the American Heart Association/American College of Cardiology.
      For example, the Diabetes Quality Improvement Project, a collaborative effort between public and private organizations to improve preventive care for persons with diabetes, including influenza vaccination, has been ongoing for more than 10 years.
      • Silver A.
      • Figge J.
      • Haskin D.L.
      • et al.
      An asthma and diabetes quality improvement project: enhancing care in clinics and community health centers.
      • Fleming B.B.
      • Greenfield S.
      • Engelgau M.M.
      • Pogach L.M.
      • Clauser S.B.
      • Parrott M.A.
      The Diabetes Quality Improvement Project: moving science into health policy to gain an edge on the diabetes epidemic.
      The National Asthma Education and Prevention Program panel identified influenza vaccination as one of several “key clinical activities that should be considered as essential for quality asthma care.”

      National Asthma Education and Prevention Program. Draft needs assessment report for potential update of the expert panel report-3(2007): guidelines for the diagnosis and management of asthma, April 2014. Bethesda, MD: National Institutes of Health, National Heart, Lung, and Blood Institute. Available at: https://www.nhlbi.nih.gov/health-pro/resources/lung/nhlbac-asthma-report. Accessed March 15, 2015.

      The American Heart Association/American College of Cardiology, together with other heart disease organizations, recommended influenza vaccination as secondary prevention for cardiovascular disease.
      • Davis M.M.
      • Taubert K.
      • Benin A.L.
      • et al.
      Influenza vaccination as secondary prevention for cardiovascular disease: a science advisory from the American Heart Association/American College of Cardiology.
      In addition, the US Department of Health and Human Services initiated a strategic framework to improve the health status of individuals with multiple chronic conditions.

      US Department of Health and Human Services. Multiple chronic conditions—a strategic framework: optimum health and quality of life for individuals with multiple chronic conditions. Washington, DC: 2010. Available at: http://www.hhs.gov/ash/initiatives/mcc/mcc_framework.pdf. Accessed March 15, 2015.

      U.S. Department of Health & Human Services. HHS initiative on multiple chronic conditions. Available at: http://www.hhs.gov/ash/initiatives/mcc/. Accessed March 15, 2015.

      • Parekh A.K.
      • Goodman R.A.
      • Gordon C.
      • Koh H.K.
      HHS Interagency Workgroup on Multiple Chronic Conditions
      Managing multiple chronic conditions: a strategic framework for improving health outcomes and quality of life.
      The Department of Health and Human Services framework contains a vision statement, goals, objectives, and discrete strategies for individuals with multiple chronic conditions to guide the department in coordinating its efforts internally and externally through collaborating with stakeholders to improve care coordination, maximize the use of proven self-care management and other services, provide better tools and information to providers who deliver care to persons with multiple chronic conditions, and facilitate research to fill knowledge gaps and develop beneficial interventions. The framework outlines national strategies for improving health and quality of life for individuals with multiple chronic conditions, including maximizing use of proven services like vaccination.

      US Department of Health and Human Services. Multiple chronic conditions—a strategic framework: optimum health and quality of life for individuals with multiple chronic conditions. Washington, DC: 2010. Available at: http://www.hhs.gov/ash/initiatives/mcc/mcc_framework.pdf. Accessed March 15, 2015.

      U.S. Department of Health & Human Services. HHS initiative on multiple chronic conditions. Available at: http://www.hhs.gov/ash/initiatives/mcc/. Accessed March 15, 2015.

      • Parekh A.K.
      • Goodman R.A.
      • Gordon C.
      • Koh H.K.
      HHS Interagency Workgroup on Multiple Chronic Conditions
      Managing multiple chronic conditions: a strategic framework for improving health outcomes and quality of life.
      Those ongoing activities may help improve influenza vaccination coverage among persons with high-risk conditions.
      As might be expected, this study found that vaccination coverage among persons 50-64 years of age was significantly higher than among those ages 18-49 years. This result remained after controlling for other demographic and access to care variables. As people age, the prevalence of high-risk conditions is likely to increase. In this study, the prevalence of lung disease, heart disease, and diabetes among adults 50-64 years of age were 10.8%, 13.8%, and 13.8%, respectively, compared with 6.3%, 4.6%, and 3.4%, respectively, among adults 18-49 years of age. Health care providers may be more likely to recommend influenza vaccination to persons ages 50-64 years with high-risk conditions because of a perception of greater risk for complications from influenza compared with younger persons 18-49 years of age.
      • Bridges C.B.
      • Winquist A.G.
      • Fukuda K.
      • et al.
      Advisory Committee on Immunization Practices
      Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices (ACIP).
      Health care providers should ensure that persons at high risk receive appropriate vaccinations regardless of age.
      Influenza vaccination coverage also varied substantially among persons with specific high-risk conditions, ranging from 44.0% for adults with asthma to 62.5% for those with renal disease. Lower coverage for adults with asthma might reflect their concerns that the vaccine could trigger an asthma exacerbation, making them less likely to be vaccinated, although studies found no evidence of asthma exacerbation or other severe side effects after influenza vaccination.
      • Eisner M.D.
      Asthma and influenza vaccination.
      The American Lung Association Asthma Clinical Research Centers
      The safety of inactivated influenza vaccine in adults and children with asthma.
      • Kmiecik T.
      • Sek K.
      • Górski P.
      Safety of influenza vaccination in asthmatics.
      Given that respiratory infections such as influenza can be serious in persons with asthma, the lower vaccination coverage in this risk group warrants further consideration.
      • Dower J.
      • Donald M.
      • Begum N.
      • Vlack S.
      • Ozolins I.
      Patterns and determinants of influenza and pneumococcal immunisation among adults with chronic disease living in Queensland, Australia.
      Offering influenza vaccination in the ED to those with asthma would be appropriate. Sometimes EDs may be the only place these patients interact with a medical provider.

      National Asthma Education and Prevention Program. Draft needs assessment report for potential update of the expert panel report-3(2007): guidelines for the diagnosis and management of asthma, April 2014. Bethesda, MD: National Institutes of Health, National Heart, Lung, and Blood Institute. Available at: https://www.nhlbi.nih.gov/health-pro/resources/lung/nhlbac-asthma-report. Accessed March 15, 2015.

      Physicians should consider each office or ED visit a potential opportunity to vaccinate persons with asthma.

      National Asthma Education and Prevention Program. Draft needs assessment report for potential update of the expert panel report-3(2007): guidelines for the diagnosis and management of asthma, April 2014. Bethesda, MD: National Institutes of Health, National Heart, Lung, and Blood Institute. Available at: https://www.nhlbi.nih.gov/health-pro/resources/lung/nhlbac-asthma-report. Accessed March 15, 2015.

      We found that vaccination coverage among persons who have health insurance, have a regular physician for health care, and physician contacts in the past 12 months were significantly associated with influenza vaccination. These findings remained after controlling for other variables and are consistent with other reports.
      • Egede L.E.
      • Zheng D.
      Racial/ethnic differences in influenza vaccination coverage in high-risk adults.
      • Singleton J.A.
      • Wortley P.M.
      • Lu P.J.
      Influenza vaccination of persons with cardiovascular disease in the United States.
      • Williams W.W.
      • Lu P.J.
      • Saraiya M.
      • et al.
      Factors associated with human papillomavirus vaccination among young adult women in the United States.
      Physician contact plays an important role in vaccination uptake.
      • Egede L.E.
      • Zheng D.
      Racial/ethnic differences in influenza vaccination coverage in high-risk adults.
      • Singleton J.A.
      • Wortley P.M.
      • Lu P.J.
      Influenza vaccination of persons with cardiovascular disease in the United States.
      • Lu P.J.
      • Ding D.
      • Black C.L.
      H1N1 and seasonal influenza vaccination of U.S. healthcare personnel, 2010.
      Having a regular physician and seeing a physician provide opportunities for education about influenza vaccination and offering vaccination and other prevention services. Persons with high-risk conditions may have more frequent contacts with their health care providers. Routine physician visits can provide important opportunities for providers to vaccinate persons with high-risk conditions.
      There were missed opportunities for vaccinating adults with high-risk conditions. Although our findings suggest that recent physician contacts were independently associated with influenza vaccination, we also found a substantial proportion of individuals with high-risk conditions who had visited their physicians at least 10 times within the past year, but still were not vaccinated. Based on our study, overall, 90.1% of unvaccinated individuals reported at least one visit to a health care setting where vaccination could have been provided, including 87.3% who had one or more physician contacts in the last 12 months, 15.2% who were hospitalized in the previous 12 months, and 31.7% who had visited an ED. In one study, a significant proportion of generalists and subspecialists failed to recommend influenza vaccination to their high-risk patients.
      • Nichol K.L.
      • Zimmerman R.
      Generalist and subspecialist physicians' knowledge, attitudes, and practices regarding influenza and pneumococcal vaccinations for elderly and other high-risk patients: a nationwide survey.
      Use of standing-order programs might help reduce the number of missed opportunities for vaccinating persons who have already accessed the medical system.
      • Rehm S.J.
      • Farley M.M.
      • File Jr., T.M.
      • et al.
      Higher pneumococcal disease vaccination rates needed to protect more at-risk US adults.
      • Poland G.A.
      • Shefer A.M.
      • McCauley M.
      • et al.
      Standards for adult immunization practices.
      National Center for Immunization and Respiratory Diseases
      General recommendations on immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP).
      In addition, it is also important for subspecialists to recommend and offer influenza vaccination to high-risk adults. Although primary care physicians are the predominant providers for adults with chronic conditions in the health care system, subspecialists also see these patients with great frequency.
      • Davis M.M.
      • Wortley P.M.
      • Ndiaye S.M.
      • Cowan A.E.
      • Osta A.D.
      • Clark S.J.
      Influenza vaccine for high-risk non-elderly adults: a national survey of subspecialists.
      However, one study indicated that about 22% of subspecialists did not stock the influenza vaccine. The most common factor in the decision to not stock vaccine was the perception that patients will receive the vaccine elsewhere.
      • Davis M.M.
      • Wortley P.M.
      • Ndiaye S.M.
      • Cowan A.E.
      • Osta A.D.
      • Clark S.J.
      Influenza vaccine for high-risk non-elderly adults: a national survey of subspecialists.
      Subspecialists, especially cardiologists, were less likely to stock and recommend influenza vaccine.
      • Davis M.M.
      • Wortley P.M.
      • Ndiaye S.M.
      • Cowan A.E.
      • Osta A.D.
      • Clark S.J.
      Influenza vaccine for high-risk non-elderly adults: a national survey of subspecialists.
      • Davis M.M.
      • Wortley P.M.
      • Ndiaye S.M.
      • Woods M.G.
      • Clark S.J.
      National availability of influenza vaccine among medical subspecialty practices.
      To reduce missed opportunities overall, subspecialists should be encouraged to vaccinate high-risk patients or refer their patients for vaccination.
      • Davis M.M.
      • Wortley P.M.
      • Ndiaye S.M.
      • Cowan A.E.
      • Osta A.D.
      • Clark S.J.
      Influenza vaccine for high-risk non-elderly adults: a national survey of subspecialists.
      • Davis M.M.
      • Wortley P.M.
      • Ndiaye S.M.
      • Woods M.G.
      • Clark S.J.
      National availability of influenza vaccine among medical subspecialty practices.
      One limitation should be considered in interpreting these results. Information on influenza vaccination was self-reported and may be subject to recall bias. However, self-reported seasonal influenza vaccination status among older adults has been shown to have relatively high agreement with vaccination status ascertained from medical records.
      • Donald R.M.
      • Baken L.
      • Nelson A.
      • Nichol K.L.
      Validation of self-report of influenza and pneumococcal vaccination status in elderly outpatients.
      • Zimmerman R.K.
      • Raymund M.
      • Janosky J.E.
      • Nowalk M.P.
      • Fine M.J.
      Sensitivity and specificity of patient self-report of influenza and pneumococcal polysaccharide vaccinations among elderly outpatients in diverse patient care strata.
      • Mangtani P.
      • Shah A.
      • Roberts J.A.
      Validation of influenza and pneumococcal vaccine status in adults based on self-report.
      Influenza vaccination coverage among adults with high-risk conditions remains suboptimal. In 2012-2013, an estimated 40 million adults ages 18-64 years had underlying medical conditions, but only about 50% had received the vaccine, and 90% of unvaccinated individuals may have missed at least one potential opportunity for receiving vaccination. Even though the influenza vaccination was expanded to include all persons ≥6 months of age in the 2010-2011 season, the ACIP continued to emphasize that persons with high-risk conditions should be a focus of vaccination efforts.
      • Fiore A.E.
      • Uyeki T.M.
      • Broder K.
      • et al.
      Centers for Disease Control and Prevention (CDC)
      Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices.
      Substantial improvement in annual influenza vaccination of adults with high-risk conditions is needed to maximally reduce the health impact of influenza. Primary care providers, subspecialists, and pharmacists should routinely recommend and offer vaccinations when patients access the medical system.
      National Vaccine Advisory Committee
      Recommendations from the National Vaccine Advisory committee: standards for adult immunization practice.
      Expanded access through greater use of complimentary settings and vaccine providers, and better use of evidence-based practices at medical sites (eg, standing orders, and reminder/recall notification) are important to improving influenza vaccination coverage further.
      • Poland G.A.
      • Shefer A.M.
      • McCauley M.
      • et al.
      Standards for adult immunization practices.
      Guide to Community Preventive Services
      Increasing appropriate vaccination: health care system-based interventions implemented in combination. Available at.

      Acknowledgment

      We thank James A. Singleton and Stacie M. Greby for their thoughtful review of the manuscript.

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