https://immattersacp.org/weekly/archives/2016/02/09/5.htm

Statins associated with fewer major adverse coronary events, mortality in those with low ankle-brachial index

Clinicians should optimize therapy for people with clear indications for statin therapy, including those with diabetes, an editorial suggested.


Statin therapy was associated with a reduction in major adverse coronary events (MACE) and all-cause mortality among participants without clinical cardiovascular disease (CVD) but with asymptomatic peripheral arterial disease, regardless of its low CVD risk, a study from Spain found.

Researchers obtained data from 2006 through 2013 from a database comprising 5 million patients attended by the 3,414 general practitioners in the 274 primary care practices managed by the Catalan Institute of Health, consisting of approximately 80% of this region of Spain or 10% of the entire Spanish population. Patients were ages 35 to 85 years with an ankle-brachial index (ABI) ≤0.95 and without clinically recognized CVD. Participants were categorized as statin nonusers or new users (first prescription or represcribed after ≥6 months).

The matched-pair cohort included 5,480 patients (mean age, 67 years; 44% women) matched 1:1 by inclusion date and propensity score for statin treatment. The 10-year coronary heart disease risk was low (median, 6.9%). Median follow-up was 3.6 years. The study results were published online Feb. 8 by the Journal of the American College of Cardiology.

Differences were observed in MACE and all-cause mortality rates (in events per 1,000 person-years). MACE rates were 19.7 (95% CI, 17.2 to 22.5) in new users versus 24.7 (95% CI, 21.8 to 27.8) in nonusers. Mortality rates were 24.8 (95% CI, 22.0 to 27.8) in new users versus 30.3 (95% CI, 27.2 to 33.6) in nonusers. Hazard ratios for primary endpoint events significantly differed between groups, as well, the authors noted. MACE decreased relatively by 20% (95% CI, 3% to 34%) and all-cause mortality decreased relatively by 19% (95% CI, 3% to 32%). The 1-year numbers needed to treat were 200 for MACE and 239 for all-cause mortality.

The researchers noted that the absolute reduction was comparable to that achieved in secondary prevention.

“If these results are confirmed, they could easily be applied in clinical practice and have a large effect on CVD prevention, because a non-negligible 5% to 17% of individuals have the characteristics reported here,” the authors wrote. “Medical prescriptions in primary prevention account for part of the increasing economic burden of CVD in developed countries, so this strategy could be focused on actual high-risk individuals, ensuring cost-effectiveness.”

An editorial countered that it is unlikely that findings from the study will change clinical practice. Most patients in the study qualified for statin therapy even before the ABI measurement, and it is likely that the number of people with a low ABI and no other indication for cholesterol-lowering therapy is small.

“[F]irst clinicians should optimize therapy for people with clear indications for statin therapy, including those with diabetes mellitus,” the editorial stated. “The number of people with a low ABI who do not have another indication for ABI screening would need to be substantial to justify a clinical trial.”