Polypharmacy and mortality among nursing home residents with advanced cognitive impairment: results from the SHELTER study

Abstract

Introduction: Older adults with advanced cognitive impairment have a limited life expectancy and the use of multiple drugs is of questionable benefit in this population. The aim of the present study was to assess if, in a sample of nursing home (NH) residents with advanced cognitive impairment, the effect of polypharmacy on mortality differs depending on estimated life expectancy.

Methods: Data were from the Services and Health for Elderly in Long TERm care (SHELTER) project, a study collecting information on residents admitted to 57 NHs in 8 European countries. Polypharmacy was defined as the concomitant use of 10 or more drugs. Limited life expectancy was estimated based on an Advanced Dementia Prognostic Tool (ADEPT) score of 13.5 or more. A Cognitive Performance Scale score of 5 or more was used to define advanced cognitive impairment. Participants were followed for 1 year.

Results: Mean age of 822 residents with advanced cognitive impairment entering the study was 84.6 (SD 8.0) years, and 630 (86.6%) were women. Overall, 123 participants (15.0%) had an ADEPT score of 13.5 or more (indicating limited life expectancy) and 114 (13.9%) were on polypharmacy. Relative to residents with ADEPT score less than 13.5, those with ADEPT score of 13.5 or higher had a lower use of benzodiazepines, antidementia drugs, and statins but a higher use of beta-blockers, digoxin, and antibiotics. Polypharmacy was associated with increased mortality among residents with ADEPT score of 13.5 or more (adjusted hazard ratio [HR] 2.19, 95% confidence interval [CI]: 1.15-4.17), but not among those with ADEPT score less than 13.5 (adjusted HR 1.10, 95% CI: 0.71-1.71).

Discussion: Polypharmacy is associated with increased mortality in NH residents with advanced cognitive impairment at the end of life.

Conclusion: These findings underline the need to assess life expectancy in older adults to improve the prescribing process and to simplify drug regimens.