Hospitalizations and deaths due to respiratory illnesses during influenza seasons: a comparison of community residents, senior housing residents, and nursing home residents.
BACKGROUND
Although research indicates that influenza is a major cause of morbidity and mortality among older adults, few studies have tried to identify which seniors are particularly at risk of experiencing complications of influenza. The purpose of this study was to compare hospitalizations and deaths due to respiratory illnesses during influenza seasons among seniors (aged 65+) living in the community, senior residences (apartments reserved for seniors), and nursing homes.


METHODS
Using administrative data, all hospital admissions and deaths due to respiratory illnesses (pneumonia and influenza, chronic lung disease, and acute respiratory diseases) were identified for all individuals aged 65 and older living in Winnipeg, Canada (approximately 88,000 individuals) during four influenza seasons (1995-1996 to 1998-1999).


RESULTS
Hospitalization and death rates for respiratory illnesses increased significantly during influenza seasons, compared to fall periods (e.g., 42.7 vs 25.2 hospitalizations per 1000 population aged 80 and older). Moreover, hospitalization rates for pneumonia and influenza, chronic lung disease, and acute respiratory diseases were higher among individuals living in senior residences (42.5 per 1000 for all respiratory illnesses combined) than their counterparts living in the community (22.8 per 1000). Furthermore, deaths due to pneumonia and influenza and chronic lung disease were higher among senior housing residents (4.2 per 1000) than community residents (2.6 per 1000) and were particularly high among nursing home residents (52.1 per 1000).


CONCLUSIONS
Individuals living in seniors residences are at increased risk of being hospitalized for and dying of respiratory illnesses during influenza seasons. Given that influenza vaccination is currently the best method to reduce influenza-associated illnesses among seniors, this suggests that influenza vaccination strategies should be targeted at this population.
Menec
Verena H
VH
Department of Community Health Sciences and Manitoba Centre for Health Policy, The University of Manitoba, Winnipeg, Canada. vmenec@cpe.umanitoba.ca
MacWilliam
Leonard
L
Aoki
Fred Y
FY
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002170:Canada / Q000453:epidemiology; D003153:Community Health Services; D005260:Female; D006798:Housing; D006801:Humans; D007251:Influenza, Human / Q000150:complications* / Q000401:mortality* / Q000628:therapy; D008297:Male; D009735:Nursing Homes; D010343:Patient Admission; D012111:Residence Characteristics; D012140:Respiratory Tract Diseases / Q000209:etiology* / Q000401:mortality* / Q000628:therapy; D012307:Risk Factors; D012621:Seasons; D016019:Survival Analysis; D016896:Treatment Outcome