Impact of inappropriate drug use on mortality and functional status in representative community dwelling elders

Abstract

Background: The predictive validity of Drug Utilization Review (DUR) and drugs-to-avoid criteria in elders is unknown.

Objectives: To evaluate the relationship between use of inappropriate drugs as determined by these explicit criteria and mortality and decline in functional status in community dwelling elders.

Research design: Cohort study.

Subjects: The fourth wave (3234 participants) of the Duke Established Populations for Epidemiologic Studies of the Elderly.

Measures: Two sets of inappropriate drug-use criteria: (1) DUR with respect to dosage, duplication, drug-drug interactions, duration, and drug-disease interactions; and (2) Beers-modified criteria regarding drugs-to-avoid were applied to drug use reported in an in-home interview. Death was identified from the National Death Index; change in four functional status measures (basic self-care, intermediate self-care, complex self-management, physical function) was determined during the following 3 years.

Results: Use of inappropriate drugs identified by either set of criteria was not significantly associated with mortality. The drugs-to-avoid criteria identified no significant associations between use of these drugs and decline in functional status. With DUR criteria, however, the association between use of inappropriate drugs and basic self-care was significant and pronounced among those with drug-drug or drug-disease interaction problems (Adj. OR 2.04; 95% CI 1.32-3.16).

Conclusions: Identifying the impact of inappropriate drug use may depend on the criteria applied. Further studies are needed that measure additional outcomes and use alternate measures of inappropriate drug use.