Nurse-led adherence support in hypertension: a randomized controlled trial

BACKGROUND: Lack of medication adherence is a common reason for poor control of blood pressure in the community, increasing the risk of heart attacks and strokes. OBJECTIVE: To evaluate the effect of nurse-led adherence support for people with uncontrolled high blood pressure compared with usual care. METHODS: We recruited 245 women and men with uncontrolled hypertension (> or = 150/90 mmHg) from 21 general practices in Bristol, UK. Participants were randomized to receive nurse-led adherence support or usual care alone. Main outcome measures were adherence to medication ('timing compliance') and blood pressure. RESULTS: Mean baseline timing compliance (+/- SD) was high in both the intervention (90.8 +/- 15.6%) and the control group (94.5 +/- 7.6%). There was no evidence of an effect of the intervention on timing compliance at follow-up (adjusted difference in means -1.0%; 95% confidence interval (CI) -5.1 to 3.1). There was also no difference at follow-up between the groups with regard to systolic blood pressure (-2.7 mmHg; 95% CI -7.2 to 1.8) or diastolic blood pressure (0.2 mmHg; 95% CI -1.9 to 2.3). Projected costs for the primary care sector per consultation were 6.60 pound sterling for the intervention compared with 5.08 pound sterling for usual care. CONCLUSION: In this study, adherence to blood pressure medication was much higher than previously reported. There was no evidence of an effect of nurse-led adherence support on medication adherence or blood pressure compared with usual care. Nurse-led adherence support was also more expensive from a primary care perspective.