Risk of pneumonia in elderly nursing home residents using typical versus atypical antipsychotics

Abstract

Background: Antipsychotic medications are extensively used in nursing homes for management of behavioral and psychiatric disorders in the elderly. Prior research suggests that pneumonia is one of the common causes of anti psychotic-related mortality in this population. None of the studies compared typical and atypical antipsychotics with respect to pneumonia.

Objective: To examine the risk of pneumonia with use of typical versus atypical antipsychotics in dual eligible elderly nursing home residents.

Methods: The study involved a retrospective cohort design matched on propensity score using Medicare and Medicaid Analytical eXtract data from 4 US states. The study population included all elderly dual eligible (Medicaid and Medicare) nursing home residents (aged ≥65 years) who initiated antipsychotics any time between July 1, 2001, and December 31, 2003. The risk of pneumonia during the 6-month follow-up period was modeled using a Cox proportional model and extended Cox hazard model stratified on matched pairs based on propensity score, using atypical agents as the reference category.

Results: Analysis of Medicaid-Medicare data revealed that there were 49,904 new antipsychotic (46,293 atypical and 3611 typical) users in the unmatched cohort and 7218 (3609 atypical and 3609 typical) users in the matched cohort. The unadjusted rate of pneumonia was 8.17% (4.61 events per person year) for atypical users and 5.21% (5.21 events per person year) for typical users.

The results: HR 1.17, 95% CI 0.83-1.66; and 50-180 days: HR 1.36, 95% CI 0.87-2.14) suggest that there was no significant difference in the risk of pneumonia among typical and atypical users.

Conclusions: The study found no differential risk of pneumonia between typical versus atypical antipsychotic use in dual eligible nursing home residents. Given the differential risk of mortality with typical and atypical antipsychotic use in nursing homes, more research is needed to evaluate other contributory factors of mortality with respect to these 2 antipsychotic classes.