Trials to improve blood pressure through adherence to antihypertensives in stroke/TIA: systematic review and meta-analysis.

BACKGROUND

The purpose of this study was to determine whether interventions including components to improve adherence to antihypertensive medications in patients after stroke/transient ischemic attack (TIA) improve adherence and blood pressure control.

METHODS AND RESULTS

We searched MEDLINE, EMBASE, CINAHL, BNI, PsycINFO, and article reference lists to October 2012. Search terms included stroke/TIA, adherence/prevention, hypertension, and randomized controlled trial (RCT). Inclusion criteria were participants with stroke/TIA; interventions including a component to improve adherence to antihypertensive medications; and outcomes including blood pressure, antihypertensive adherence, or both. Two reviewers independently assessed studies to determine eligibility, validity, and quality. Seven RCTs were eligible (n=1591). Methodological quality varied. All trials tested multifactorial interventions. None targeted medication adherence alone. Six trials measured blood pressure and 3 adherence. Meta-analysis of 6 trials showed that multifactorial programs were associated with improved blood pressure control. The difference between intervention versus control in mean improvement in systolic blood pressure was -5.3 mm Hg (95% CI, -10.2 to -0.4 mm Hg, P=0.035; I(2)=67% [21% to 86%]) and in diastolic blood pressure was -2.5 mm Hg (-5.0 to -0.1 mm Hg, P=0.046; I(2)=47% [0% to 79%]). There was no effect on medication adherence where measured.

CONCLUSIONS

Multifactorial interventions including a component to improve medication adherence can lower blood pressure after stroke/TIA. However, it is not possible to say whether or not this is achieved through better medication adherence. Trials are needed of well-characterized interventions to improve medication adherence and clinical outcomes with measurement along the hypothesized causal pathway.