To quantify effectiveness of lifestyle interventions for hypertension.
Electronic bibliographic databases from 1998 onwards, existing guidelines, systematic reviews.
We included randomized, controlled trials with at least 8 weeks' follow-up, comparing lifestyle with control interventions, enrolling adults with blood pressure at least 140/85 mmHg. Primary outcome measures were systolic and diastolic blood pressure. Two independent reviewers selected trials and abstracted data; differences were resolved by discussion.
We categorized trials by type of intervention and used random effects meta-analysis to combine mean differences between endpoint blood pressure in treatment and control groups in 105 trials randomizing 6805 participants. Robust statistically significant effects were found for improved diet, aerobic exercise, alcohol and sodium restriction, and fish oil supplements: mean reductions in systolic blood pressure of 5.0 mmHg [95% confidence interval (CI): 3.1–7.0], 4.6 mmHg (95% CI: 2.0–7.1), 3.8 mmHg (95% CI: 1.4–6.1), 3.6 mmHg (95% CI: 2.5–4.6) and 2.3 mmHg (95% CI: 0.2–4.3), respectively, with corresponding reductions in diastolic blood pressure. Relaxation significantly reduced blood pressure only when compared with non-intervention controls. We found no robust evidence of any important effect on blood pressure of potassium, magnesium or calcium supplements.
Patients with elevated blood pressure should follow a weight-reducing diet, take regular exercise, and restrict alcohol and salt intake. Available evidence does not support relaxation therapies, calcium, magnesium or potassium supplements to reduce blood pressure.
aUniversity of Newcastle upon Tyne, Centre for Health Services Research, Newcastle upon Tyne
bUniversity of Durham, School for Health, Wolfson Research Unit, Stockton-on-Tees
cUniversity of Leeds, School of Healthcare, Leeds
dUniversity of Leicester, Department of Cardiovascular Sciences, University of Leicester Clinical Sciences Building, Leicester Royal Infirmary, Leicester
eUniversity of Newcastle upon Tyne, Clinical Research Facility, Royal Victoria Infirmary, Newcastle upon Tyne, UK
Received 8 March, 2005
Revised 29 July, 2005
Accepted 19 September, 2005
Correspondence and requests for reprints to Dr H.O. Dickinson, University of Newcastle upon Tyne, Centre for Health Services Research, 21 Claremont Place, Newcastle upon Tyne, NE2 4AA, UK Tel: +44 191 222 3699; fax: +44 191 222 6043; e-mail: email@example.com
Sponsorship: This work was undertaken with funding from the National Institute for Clinical Excellence. The funding body was not involved in any aspect of the design or conduct of the review or interpretation of findings. The views expressed are those of the authors and not necessarily those of the funding body.
Potential conflicts of interest: G.A.F. and B.W. have received honoraria from a number of pharmaceutical companies for lectures and consultancy, and grant support for clinical trials from medical charities and the pharmaceutical industry.
Preliminary work on the review was reported in a recent national clinical guideline commissioned by the National Institute for Clinical Excellence, see http://www.nice.org.uk/page.aspx?o=217976.
Part of this systematic review has been prepared under the aegis of The Cochrane Collboration. The Collaboration's publication policy permits journals to publish reviews, with priority if required, but permits The Cochrane Collaboration also to publish and disseminate such reviews.