Review of prescription medications in home-based older adults with stroke: a pilot study.

BACKGROUND: Pharmacological intervention for comorbid management and stroke prevention may increase polypharmacy, inappropriately prescribed drugs (IPDs), and potential drug-drug interactions (PDDIs) among older adults with a history of stroke.

OBJECTIVE: The objective of this study was to determine prevalence and incidence of polypharmacy, IPDs, and PDDIs in a cohort of home-based older adults with self-reported stroke living in New York and Florida.

METHODS: Using a cross-sectional design, we determined the prevalence of PDDIs in 191 older adults with a history of stroke. We quantified the odds of PDDIs using bivariate logistic regression. Using a 3-year retrospective longitudinal design, we determined the relative risk (RR) of PDDIs in 41 new cases (New York) with polypharmacy and IPD. The independent variables were polypharmacy and IPDs, and the dependent variable was PDDIs.

RESULTS: Subjects from Florida were older, had higher frequencies of some medical conditions, and used more medications, but the prevalence rates of PDDIs showed similar trends for the 2 states: 60% (New York) and 86% (Florida). The 3 strongest predictors of PDDIs in New York were polypharmacy (> or = 4 drugs) (odds ratio [OR]=10.3; 95% confidence interval [CI]=3.8-27.8); IPDs (OR=8.4; 95% CI=2.7-25.5); and having a heart condition (OR=6.0; 95% CI=1.6-22.8). The logistic model yielded one predictor for PDDIs in Florida: polypharmacy (> or = 4 drugs) (OR=9.7; 95% CI=1.4-65.4). The 3-year RR for PDDIs (New York) was 1.8 (95% CI=1.2-2.8) from polypharmacy and 2.1 (95% CI=1.3-3.3) from IPDs.

CONCLUSIONS: Although this research is exploratory and used a small convenience sample, the estimates obtained suggest consideration of prospective hypothesis testing using a larger database and a greater number of subjects using more recent medications. Prospective examination of developing drug-drug interactions in this way will enhance the generalizability of these findings. This study shows similarities in the prevalence rates between 2 historical cohorts in 2 states, thereby suggesting plausibility of findings.