The burden of community-acquired pneumonia in seniors: results of a population-based study

Michael L Jackson, Kathleen M Neuzil, William W Thompson, David K Shay, Onchee Yu, Christi A Hanson, Lisa A Jackson, Michael L Jackson, Kathleen M Neuzil, William W Thompson, David K Shay, Onchee Yu, Christi A Hanson, Lisa A Jackson

Abstract

Background: Pneumonia is recognized as a leading cause of morbidity in seniors. However, the overall burden of this disease--and, in particular, the contribution of ambulatory cases to that burden--is not well defined. To estimate rates of community-acquired pneumonia and to identify risk factors for this disease, we conducted a large, population-based cohort study of persons aged >or=65 years that included both hospitalizations and outpatient visits for pneumonia.

Methods: The study population consisted of 46,237 seniors enrolled at Group Health Cooperative who were observed over a 3-year period. Pneumonia episodes presumptively identified by International Classification of Diseases, Ninth Revision, Clinical Modification codes assigned to medical encounters were validated by medical record review. Characteristics of participants were defined by administrative data sources.

Results: The overall rate of community-acquired pneumonia ranged from 18.2 cases per 1000 person-years among persons aged 65-69 years to 52.3 cases per 1000 person-years among those aged >or=85 years. In this population, 59.3% of all pneumonia episodes were treated on an outpatient basis. In multivariate analysis, risk factors for community-acquired pneumonia included age, male sex, chronic obstructive pulmonary disease, asthma, diabetes mellitus, congestive heart failure, and smoking.

Conclusions: On the basis of these data, we estimate that roughly 915,900 cases of community-acquired pneumonia occur annually among seniors in the United States and that approximately 1 of every 20 persons aged >or=85 years will have a new episode of community-acquired pneumonia each year.

Figures

Table A1
Table A1
Definition of baseline covariates.
Table 1
Table 1
Baseline characteristics of study subjects, by age group
Table 2
Table 2
Rates of community-acquired pneumonia (CAP) and the proportion of patients hospitalized, by age group, during the study period.
Figure 1
Figure 1
Biweekly rates of all cases of community-acquired pneumonia (CAP) among seniors in Group Health Cooperative (GHC), including hospitalizations and outpatient visits for CAP, during the study period. Periods of influenza virus circulation, as defined by Centers for Disease Control and Prevention surveillance data, are shaded [7–10]. For comparison, the biweekly proportion of all deaths in the United States attributed to pneumonia and influenza (P&I), as reported by national vital statistics data, is also presented [6].
Table 3
Table 3
Results of multivariate Cox proportional analyses of time to first event for the outcomes of chart review-confirmed hospitalizations for community-acquired pneumonia (CAP), outpatient visits for CAP, and all CAP.

References

    1. Marston BJ, Plouffe JF, File TM, Jr, et al. Incidence of community-acquired pneumonia requiring hospitalization. results of a population-based active surveillance study in Ohio. The Community-Based Pneumonia Incidence Study Group. Arch Intern Med. 1997;157:1709–18.
    1. Hoyert DL, Arias E, Smith BL, Murphy SL, Kochanek KD. Deaths: final data for 1999. Natl Vital Stat Rep. 2001;49:1–113.
    1. Kaplan V, Angus DC, Griffin MF, Clermont G, Scott Watson R, Linde-Zwirble WT. Hospitalized community-acquired pneumonia in the elderly: age- and sex-related patterns of care and outcome in the United States. Am J Respir Crit Care Med. 2002;165:766–72.
    1. Kochanek KD, Smith B. Deaths: preliminary data for 2002. National Vital Statistics Reports. 2004;52:1–48.
    1. Jackson LA, Neuzil KM, Yu O, et al. Effectiveness of pneumococcal polysaccharide vaccine in older adults. N Engl J Med. 2003;348:1747–55.
    1. Vital statistics mortality data, multiple cause detail, 1998–2000. Hyattsville, MD: National Center for Health Statistics; 2000.
    1. Centers for Disease Control and Prevention Update: influenza activity—United States and worldwide, 2000–01 season, and composition of the 2001–02 influenza vaccine. MMWR Morb Mortal Wkly Rep. 2001;50:466–79.
    1. Centers for Disease Control and Prevention Update: influenza activity—United States and worldwide, 1997–98 season, and composition of the 1998–99 influenza vaccine. MMWR Morb Mortal Wkly Rep. 1998;47:280–4.
    1. Centers for Disease Control and Prevention Update: influenza activity—United States and worldwide, 1998–99 season, and composition of the 1999–2000 influenza vaccine. MMWR Morb Mortal Wkly Rep. 1999;48:374–8.
    1. Centers for Disease Control and Prevention Update: influenza activity—United States and worldwide, 1999–2000 season, and composition of the 2000–01 influenza vaccine. MMWR Morb Mortal Wkly Rep. 2000;49:375–81.
    1. Fisher LD, Lin DY. Time-dependent covariates in the Cox proportional-hazards regression model. Annu Rev Public Health. 1999;20:145–57.
    1. Koepsell T, Weiss N. Epidemiologic methods: studying the occurrence of illness. New York: The University of Chicago Press; 2003.
    1. Jokinen C, Heiskanen L, Juvonen H, et al. Incidence of community-acquired pneumonia in the population of four municipalities in eastern Finland. Am J Epidemiol. 1993;137:977–88.
    1. Koivula I, Sten M, Leinonen M, Makela PH. Clinical efficacy of pneumococcal vaccine in the elderly: a randomized, single-blind population-based trial. Am J Med. 1997;103:281–90.
    1. Foy HM, Cooney MK, Allan I, Kenny GE. Rates of pneumonia during influenza epidemics in Seattle, 1964 to 1975. JAMA. 1979;241:253–8.
    1. Hetzel L, Smith A. Census 2000 briefs: the 65 years of age and older population: 2000. Washington, DC: US Census Bureau; 2001.
    1. LaCroix AZ, Lipson S, Miles TP, White L. Prospective study of pneumonia hospitalizations and mortality of US older people: the role of chronic conditions, health behaviors, and nutritional status. Public Health Rep. 1989;104:350–60.
    1. Almirall J, Bolibar I, Balanzo X, Gonzalez CA. Risk factors for community-acquired pneumonia in adults: a population-based case-control study. Eur Respir J. 1999;13:349–55.
    1. Farr BM, Bartlett CL, Wadsworth J, Miller DL. Risk factors for community-acquired pneumonia diagnosed upon hospital admission. British Thoracic Society Pneumonia Study Group. Respir Med. 2000;94:954–63.
    1. Farr BM, Woodhead MA, Macfarlane JT, et al. Risk factors for community-acquired pneumonia diagnosed by general practitioners in the community. Respir Med. 2000;94:422–7.
    1. Koivula I, Sten M, Makela PH. Risk factors for pneumonia in the elderly. Am J Med. 1994;96:313–20.
    1. Almirall J, Gonzalez CA, Balanzo X, Bolibar I. Proportion of community-acquired pneumonia cases attributable to tobacco smoking. Chest. 1999;116:375–9.
    1. Glezen WP. Serious morbidity and mortality associated with influenza epidemics. Epidemiol Rev. 1982;4:25–44.
    1. Perrotta DM, Decker M, Glezen WP. Acute respiratory disease hospitalizations as a measure of impact of epidemic influenza. Am J Epidemiol. 1985;122:468–76.
    1. Neuzil KM, Reed GW, Mitchel EF, Jr, Griffin MR. Influenza-associated morbidity and mortality in young and middle-aged women. JAMA. 1999;281:901–7.

Source: PubMed

スポンサーと協力者

医学的状態

薬物療法

3
購読する