Increasing Physical Activity for the Treatment of Hypertension: A Systematic Review and Meta-Analysis

Low physical activity has been identified as a major risk factor for cardiovascular disease. Medical societies therefore recommend increased physical activity be part of any antihypertensive therapy. Focusing on patient-relevant outcomes such as mortality and cardiovascular events, this review was conducted to assess the long-term effects of interventions aiming at increasing physical activity in comparison with no such interventions on adult patients with essential hypertension. We searched for high-quality systematic reviews in MEDLINE, EMBASE, Cochrane Database of Systematic Reviews (Cochrane Reviews), Database of Abstracts of Reviews of Effects (Other Reviews) and Health Technology Assessment Database (Technology Assessments) published between 1997 and February 2009 and for randomized controlled trials (RCTs) in MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials (Clinical Trials) published before September 2012. Additional studies were identified by hand searching reference lists of reviews. RCTs with at least 24 weeks' follow-up that evaluated the effect of increased physical activity on the blood pressure of adults with essential hypertension were included in our review. Primary outcomes were all-cause mortality, cardiovascular morbidity and mortality, end-stage renal disease, quality of life and adverse events. When appropriate, we used random effects meta-analyses to determine mean difference with 95 % confidence intervals for each endpoint. All data were analysed using the Review Manager software version 5.0.24 from the Cochrane Collaboration. None of the included nine trials, covering 891 patients with hypertension, provided sufficient data on patient-relevant outcomes such as mortality, cardiovascular events or injuries related to physical activity. Information on changes in systolic and diastolic blood pressure was provided for all included trials. The majority of the included RCTs reported that increased physical activity led to a decrease in systolic and diastolic blood pressure of 5-10 and 1-6 mmHg, respectively, but due to marked heterogeneity in the meta-analyses both for systolic and diastolic blood pressure (I-2 = 70.0 and 73.0 %), no effect estimates were provided. About 50 % of the included trials were small, evaluating at most 20 participants per study group, and more than twothirds were deemed to have a high risk of bias. Although a decrease in blood pressure is shown to be a consequence of increased physical activity, RCTs of appropriate study size and quality that examine potential patient-relevant benefits or harms still need to be conducted to evaluate whether physical activity really improves the health of patients with essential hypertension.