Risk Factors for Adverse Drug Reactions in Older Subjects Hospitalized in a Dedicated Dementia Unit

Abstract

Objective: To identify risk factors for the occurrence of adverse drug reactions (ADRs) based on geriatric evaluation.

Design: Longitudinal prospective study from May 2010 to November 2011.

Setting: Dedicated acute geriatric care unit specializing in the management of patients with dementia syndrome (Alzheimer disease or related syndromes) at the University Hospital of Reims, France.

Participants: Older patients with dementia syndrome (Alzheimer disease or related syndromes).

Measurements: Sociodemographic variables and comprehensive geriatric assessment were recorded. Occurrence of ADRs was noted. Risk factors for ADR were identified by multivariate logistic regression.

Results: During the study period, 293 patients were included; average age was 82 ± 8 years; the majority were women (61.4%). Average Mini-Mental State Examination score was 13 ± 8; average activities of daily living (ADL) score was 3.6 ± 2.1. Independent risk factors for occurrence of at least one ADR were polypharmacy (≥5 drugs/day) (OR: 4.0, 95% CI: 1.1-14.1) and dependence on at least 1 ADL (OR: 2.6, 95% CI: 1.1-6.5).

Conclusions: Risk factors for ADRs were polypharmacy and dependence on at least one ADL. Our findings underline the importance of taking into consideration the characteristics of the patients when prescribing drugs in this specific population. Prescriptions should be re-evaluated at each follow-up.

Keywords: adverse drug reaction; dementia syndrome; older subject; polypharmacy.