BP-lowering drugs reduced major CV events by similar amounts in patients with and without type 2 diabetes

A 5-mm Hg reduction in systolic blood pressure (SBP) decreased the risk of major cardiovascular (CV) events in patients with or without type 2 diabetes, but the relative treatment effect was weaker in the former group, according to a recent systematic review. The participant-level analysis had a median follow-up of 4.2 years and estimated the effects of five major drug classes, including angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, beta-blockers, calcium-channel blockers, and thiazide diuretics.

The study was published by The Lancet Diabetes & Endocrinology on July 22 and summarized in the August ACP Diabetes Monthly. The following commentary by Jayson C. Carr, MD, FACP, was published in the ACP Journal Club section of Annals of Internal Medicine on Dec. 6.

In an updated analysis of Blood Pressure Lowering Treatment Trialists' Collaboration data, Nazarzadeh and colleagues included >300,000 participants across 51 clinical trials and found that relative CV benefits of hypertension treatment were smaller for patients with vs. without diabetes. Absolute risk reductions for most CV end points were similar, a finding largely explained by higher baseline CV risk in patients with diabetes. As antihypertensive treatment in patients with diabetes also delays progression of kidney and retinal disease, the benefits of pharmacologic treatment remain clear for most patients with hypertension and diabetes.

Nazarzadeh and colleagues found similar CV event reductions with different drug classes, supporting the conclusion that degree of BP lowering rather than drug used is the prime driver of CV risk reduction. The study may support a polypill (fixed-dose combination of antihypertensive and statin drugs) approach to primary CV disease prevention. However, a particular drug class will have clinical advantages for some patients—for example, angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers in patients with comorbid diabetic nephropathy or congestive heart failure. Treatment also reduced CV events across the spectrum of baseline SBP, and the authors concluded that current BP thresholds for instituting treatment are not warranted. Although all BP groups benefited from treatment, individualized treatment decisions based on clinical and other patient factors are needed.

The mean age of participants was 65 years; however, studies have shown that antihypertensive treatment reduces CV risk in older patients, including those who are >80 years of age, or are older and frail, although risks for orthostasis, associated falls, and polypharmacy need to be considered.