Changes in Medication Complexity and Post-Hospitalization Outcomes in Older Adults Hospitalized for Heart Failure

Medication regimen complexity may be an important risk factor for adverse outcomes in older adults with heart failure. However, increasing complexity is often necessary when prescribing guideline-directed medical therapy at the time of a heart failure hospitalization. We sought to determine whether increased medication regimen complexity following a heart failure hospitalization was associated with worse post-hospitalization outcomes.

This retrospective cohort study included Reasons for Geographic and Racial Differences in Stroke (REGARDS) participants aged at least 65 years hospitalized for heart failure between 2003 and 2014. We calculated changes between hospital admission and discharge in medication count (Δcount) and in the validated Medication Regimen Complexity Index (ΔMRCI), which incorporates each medication's dosage formulation, frequency, timing, and special instructions. The primary outcome was a composite of 90-day all-cause readmission and all-cause mortality post-discharge. We calculated ΔMRCI and Δcount, identified their predictors, and examined their association with the primary outcome.

Among 725 patients hospitalized for heart failure, the mean (SD) age was 77 (7.2) years, 46% were female, and 35% were Black. At discharge, nearly 75% had an increase in their medication regimen complexity and 60% had an increase in their medication count. Patients with the highest ΔMRCI and Δcount were more likely to be female and Black. Predictors of the highest ΔMRCI included Charlson comorbidity index and not being discharged home; predictors of the highest Δcount included intensive care unit stay. Approximately 48% of patients experienced a 90-day readmission or death. Neither ΔMRCI (highest versus lowest tertile; HR 1.14, 95% CI 0.86, 1.50) nor Δcount (HR 0.97, 95% CI 0.73, 1.27) were associated with 90-day outcomes.

Following a heart failure hospitalization, increased medication regimen complexity was common but was not associated with 90-day post-hospitalization outcomes. These are reassuring data, suggesting that it is reasonable for clinicians to focus on optimizing medication regimens for patients with heart failure even if it increases regimen complexity.