A propensity-matched study of the effects of chronic diuretic therapy on mortality and hospitalization in older adults with heart failure.

BACKGROUND: Non-potassium-sparing diuretics may increase mortality and hospitalizations in heart failure patients. Most heart failure patients are older adults, yet the effect of diuretics on cause-specific mortality and hospitalizations in older adults with heart failure is unknown. The objective of this propensity-matched study was to determine the effect of diuretics on mortality and hospitalizations in heart failure patients >or=65 years.
METHODS: Of the 7788 Digitalis Investigation Group participants, 4036 were >or=65 years and 3271 (81%) were receiving diuretics. Propensity scores for diuretic use for each of the 4036 patients were calculated using a non-parsimonious multivariable logistic regression model incorporating all measured baseline covariates, and were used to match 651 (85%) patients not receiving diuretics with 651 patients receiving diuretics. Effects of diuretics on mortality and hospitalization at 37 months of median follow-up were assessed using matched Cox regression models.
RESULTS: All-cause mortality occurred in 173 patients not receiving diuretics and 208 patients receiving diuretics respectively during 2056 and 1943 person-years of follow-up (hazard ratio {HR}=1.36; 95% confidence interval {CI}=1.08-1.71; p=0.009). All-cause hospitalizations occurred in 413 patients not receiving and 438 patients receiving diuretics respectively during 1255 and 1144 person-years of follow-up (HR=1.18; 95% CI=0.99-1.39; p=0.063). Diuretic use was associated with significant increased risk of cardiovascular mortality (HR=1.50; 95% CI=1.15-1.96; p=0.003).and heart failure hospitalization (HR=1.48; 95% CI=1.13-1.94; p=0.005).
CONCLUSIONS: Chronic diuretic use was associated with significant increased mortality and hospitalization in ambulatory older adults with heart failure receiving angiotensin converting enzyme inhibitor and diuretics.