Clinical Question

What is the appropriate antihypertensive treatment goal for patients with diabetes mellitus?

Bottom Line

Although most recent practice guidelines have relaxed the blood pressure goals for patients with diabetes, there are still a few holdouts that suggest aggressive treatment. This analysis shows that the ideal range for hypertension control in patients with diabetes is between 140 and 150 mm Hg; higher or lower sustained blood pressures increase mortality, the so-called J-curve. (Level of Evidence = 1a)

Synopsis

These researchers searched four databases, including the Cochrane Central library, identifying 49 studies enrolling 73,738 participants with (mostly type 2) diabetes who were treated for hypertension. Two authors independently selected articles for inclusion and extracted data. Heterogeneity and publication bias were assessed but not reported. Most studies were at low risk of bias. The studies evaluated the effect of hypertension treatment on mortality and cardiovascular events but were not specifically designed to compare benefit across different target systolic blood pressures. So, the authors got creative and looked at mortality rates based on baseline (before treatment) and attained (after treatment) systolic blood pressure. In patients with a baseline blood pressure greater than 140 mm Hg or greater than 150 mm Hg, treatment decreased all-cause mortality on average, though not by much (relative risk [RR] = 0.87; 95% confidence interval [CI], 0.78 to 0.98 and RR = 0.89; 95% CI, 0.80 to 0.99). However, cardiovascular mortality, myocardial infarction risk, and development of end-stage renal disease were decreased by 15% to 25%. If baseline blood pressure was less than 140 mm Hg, however, further treatment did not decrease all-cause mortality and significantly increased the risk of cardiovascular mortality (RR = 1.15; 95% CI, 1.00 to 1.32). These results are somewhat at variance with a meta-analysis published last year that found a reduced risk of stroke and albuminuria with treatment (JAMA. 2015;313(6):603–615).

Study design: Meta-analysis (randomized controlled trials)

Funding source: Government

Setting: Various (meta-analysis)

Reference: BrunströmMCarlbergBEffect of antihypertensive treatment at different blood pressure levels in patients with diabetes mellitus: systematic review and meta-analyses. BMJ2016;352:i717.