Association between adherence to diuretic therapy and health care utilization in patients with heart failure.

Abstract

To determine the relationship between adherence to diuretic therapy and health care utilization. Prospective, observational study. University-affiliated medical center. Forty-two patients with heart failure. Electronic monitoring of adherence to diuretic therapy (percentage of diuretic prescription container openings) and to scheduling (percentage of container openings within a specific time). All patients were prescribed a diuretic, most commonly furosemide (88%). Patients varied widely in adherence to therapy (mu = 72% +/- 30%) and to scheduling (mu = 43% +/- 30%). Education was a predictor of drug-taking adherence (p=0.0062) but not of scheduling adherence. Log-linear models revealed that poor scheduling adherence was associated with increased cardiovascular-related hospitalizations (chi2 11.63, p=0.0006) and predicted more heart failure-related hospitalizations (chi2 4.04, p=0.0444). In contrast, neither measure was significantly associated with cardiovascular- or heart failure-related emergency department visits. We found a moderate correlation between scheduling adherence and taking adherence (r = 0.6513). Patients taking a greater proportion of diuretic agents on schedule may decrease the risk of cardiovascular- and heart failure-related hospitalizations. If these findings are confirmed by a larger study, interventions to improve adherence and patient health outcomes should consider the timing of doses as well as the number of daily doses of a diuretic.