Medical Research: What is the background for this study? What are the main findings?
Dr. Sundström: High blood pressure is the most important risk factor for premature death globally. The number of people with hypertension is increasing, with one billion people currently affected worldwide. Most of these have mild hypertension (a systolic blood pressure of 140 to 159 mm Hg and/or a diastolic blood pressure of 90 to 99 mm Hg) and no previous cardiovascular disease. The optimal management of this large group is uncertain, as no single trial of blood pressure lowering has provided clear evidence of treatment benefits for such persons.
In this systematic review and meta-analysis of 13 randomized controlled trials including more than 15000 people with mild hypertension and without previous known cardiovascular disease, blood pressure-lowering drug therapy decreased strokes by 28%, cardiovascular deaths by 25%, and total deaths by 22%. Achieved blood pressure reduction and numbers of events were small.
Medical Research: What should clinicians and patients take away from your report?
Dr. Sundström: Blood pressure-lowering treatment is likely to reduce the risk of a number of important adverse health outcomes for patients with blood pressures in the mild hypertension range in the primary preventive setting. The benefit will mainly depend on the size of the blood pressure reduction achieved and the level of baseline risk. Ultimately, resourcing will determine how large a proportion of the population with uncomplicated mild hypertension can be treated. Estimation of cardiovascular risk may aid prioritization among this large patient group.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Sundström: A definitive, adequately powered, large-scale trial amongst patients with uncomplicated mild hypertension would be an important addition to the evidence base. Until then, decision-making using absolute risk assessment may be the best approach for blood pressure lowering in patients with mild hypertension.