Appropriate reductions in compliance among well-controlled hypertensive patients

Abstract

Physicians have traditionally viewed partial compliance with medications as a concern only in hypertensive patients whose blood pressure (BP) is poorly controlled. However, partial compliance also occurs in patients whose BP has become normal on medications; in them, reduced compliance may indicate that they have been prescribed more medication than they need. During enrollment for a study of medication reduction in hypertensive patients, we identified 118 male veterans who were eligible for the study because their diastolic BP had been less than 95 mmHg for more than 6 months. Fifty-nine of these patients (50.0%) agreed to participate in the study, of whom 71% successfully reduced or stopped ("stepped down") one or more of their antihypertensive drugs over a 1-year period. The 59 patients who did not enroll continued to receive routine care for hypertension in the clinic without intensive efforts at stepdown. Nevertheless, 24% of these patients reduced or stopped at least one medication over the same time period. In the year prior to the study, 29 of the 118 eligible patients (24.6%) had obtained less than 80% of their medications, measured by pharmacy refill records. Compliance in obtaining antihypertensive medications prior to the study was lower among eligible patients who stepped down medications during the study year (90.4% +/- 18.7%) than in those who did not (102.1% +/- 26.1%, p = 0.006). After adjustment for other predictors of stepdown (number of medications, duration of clinic enrollment, and pre-reduction systolic BP), each 10% increase in compliance among all eligible patients was associated with a reduction in the odds ratio for successful stepdown of 0.8 (95% CI 0.5-1.0, p = 0.01). We conclude that many well-controlled hypertensives appropriately obtain less medications than they are prescribed. Such patients should be considered for reduction of antihypertensive drugs.