Influenza Vaccine Effectiveness among Elderly People with Chronic Diseases, Pitsanulok Province, 2008-2009
Keywords:
Influenza, vaccine effectiveness, elderly, chronic diseasesAbstract
Background: This study evaluated influenza vaccine effectiveness among elderly people with chronic medical conditions during 2008-2009. The objectives were to measure vaccine effectiveness for preventing clinical influenza, hospitalization with medical condition and death from all causes.
Methods: The patients with influenza like illness or hospitalized with medical condition were tested for influenza confirmation. We used prospective cohort study, among people aged 60 years old or above who had at least one of 7 chronic diseases (that were specified as a criteria for receiving influenza vaccine) who lived in Muang district of Pitsanulok province. The volunteers were followed up via phone every 2 weeks for 12 months to compare the outcomes between vaccinated and unvaccinated groups. The specimens were sent to Regional medical science center 2, Pitsanulok province or National Institute of Health, Nonthaburi province.
Results: Totally, there were 1,033 volunteers participated in this study. Among them, only 2 persons withdrawn from the study. Three hundred and sixty persons (34.85%) were vaccinated and 673 (65.15%) were unvaccinated. During the follow up period, there were 224 developed influenza like illness, 257 hospitalized with medical conditions and 39 deaths. Total 51episode were confirmed with influenza. After adjustment for confounder, the effectiveness of vaccine against clinical influenza was 35% (95%CI = -22%-65%), hospital admission with medical condition 24% (95%CI = 1%-42%) and death from all cause 54% (95%CI = 3%-79%), the later 2 were statistically significant.
Conclusions: Influenza vaccine effectively prevented hospitalization with medical condition and death from all causes among elderly people with chronic medical condition. The effectiveness against clinical influenza was not clear but this figure should be under estimated since we could not collect second serum to confirm influenza among those people who were died. Due to the finding of good effectiveness in preventing severe illness and deaths, the influenza vaccine should be continued among elderly people.
References
Karwat KJ, Szpotanska M, Szulc Z, et al. The influence of influenza vaccination on asthma and chronic obstructive pulmonary disease. Pneumonol Alergol Pol 2006;74(1):80-3.
Vila-Córcoles A, Ochoa O, de Diego C, et al. Effects of annual influenza vaccination on Winter mortality in elderly people with chronic pulmonary disease. International Journal of Clinical Practice 2008; 62(1):10-7.
Gurfinkel EP and de al Fuente RL. Two-Year FollowUp of the FLU Vaccination Acute Coronary Syndrome (FLUVACS) Registry, Texas Heart Institute Journal 2004;31(1):28-32.
Davis MM, Taubert K, Benin AL, Brown DW, Mensah GA, Baddour LM, et al. Influenza Vaccination as Secondary Prevention for Cardiovascular Disease: A Science Advisory From the American Heart Association/American College of Cardiology: Endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation, the American Association of Critical Care nurses, the American Association of Heart Failure Nurses, the American Diabetes Association, the Association of Black Cardiologists, Inc., the Heart Failure Society of American Academy of Nurse Practitioners supports the recommendations of this scientific advisory: This science advisory is consistent with the recommendations of the Centers of Disease Control and Prevention and the Advisory Committee on Immunization Practices. Circulation 2006;114:1549-53.
Heffelfinger JD, Heckbert SR, Psaty BM, Weiss NS, Thompson WW, Bridges CB, Jackson LA. Influenza Vaccination and Risk of Incident Myocardial Infarction. Human Vaccine 2006;2(4):161-6.
Grau AJ, Fischer B, Barth C, et al. Influenza Vaccination Is Associated With a Reduced Risk of Stroke. Stroke 2005;36:1501-6.
Hall WH, Ramachandran R, Narayan S, Jani AB, Vijayakumar S. An electronic application for rapidly calculating Charlson comorbidity score. BMC Cancer 2004;4(94):1-8.
Rothman KJ, Greenland S, Lash TL. Modern Epidemiology, Third Edition. Philadelphia: Lippincott Williams & Wilkins; 2008.
Jackson LA, Jackson ML, Nelson JC, Neuzil KM, Weiss NS. Evidence of bias in estimates of influenza vaccine effectiveness in seniors. Int J Epidemiol 2005;35:337-44.
Jackson LA, Nelson JC, Benson P, Neuzil KM, Reid RJ, et al. Functional status is a confounder of the association of influenza vaccine and risk of all cause mortality in seniors. Int J Epidemiol 2005;35:345-52.
Centers for Disease Control and Prevention. Flu Vaccine Effectiveness: Questions and Answers for Health Professionals. [cited 2011 October 20]. Available from: http://www.cdc.gov/flu/professionals/vaccination/effectivenessqa.htm.
Anthony F. Recent developments in seasonal influenza epidemiology and prevention. Clinician Outreach and Communication Activity (COCA) Teleconference. [cited 2008 May 27]. Available from: http://emergency.cdc.gov/coca/ppt/FinalFiore COCAinfluenza08.ppt.
Herrera GA, Iwane MK, Cortese M, et al. Influenza vaccine effectiveness among 50-64-year-old persons during a season of poor antigenic match between vaccine and circulating influenza virus strains: Colorado, United States, 2003-2004. Vaccine 2007; 25(1):154-60.
Centers for Disease Control and Prevention. Interim Adjusted Estimates of Seasonal Influenza Vaccine Effectiveness — United States, February 2013. MMWR 2013; 62(7):119-23.
Gross PA, Hermogenes AW, Sacks HS, Lau J and Levandowski RA. The efficacy of influenza vaccine in elderly persons: a meta-analysis and review of the literature. Ann Intern Med 1995;123:518-27.
Vu T, Farish S, Jenkins M, Kelly H.A meta-analysis of effectivetiveness of influenza vaccine in persons aged 65 years and over iving in the community. Vaccine 2002; 20(13-14):1831-6.
Nichol KL. Influenza vaccination in the elderly, impact on hospitalization and mortality. Drug Aging 2005;22(6):495-515.
Centers for Disease Control and Prevention. What You Should Know for the 2012-2013 Influenza Season, Questions & Answers. [cited 2013 March 16]. Available from: http://www.cdc.gov/flu/past seasons/1213season.htm.
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