Statins Helpful in Peripheral Artery Disease

Patients with critical limb ischemia who took statins had significantly fewer major cardiovascular events and limb amputations, a retrospective study indicated.

Review of 380 patients with critical limb ischemia showed that those who had taken statins were half as likely to suffer myocardial infarction, stroke, or death from any cause (propensity-adjusted hazard ratio 0.53, 95% 0.28-0.99) compared with those not on statins, reported John R. Laird, MD, of the University of California Davis, and colleagues.

Rates of a composite of death and limb amputation were also halved in the statin-takers (HR 0.53, 95% CI 0.35-0.98), the researchers reported in an article scheduled for online publication in the Journal of the American College of Cardiology.

"The improved rates of 1-year major adverse cardiovascular and cerebrovascular events with statin use strengthens the evidence supporting the guideline recommendations of statin therapy for all peripheral artery disease (PAD) patients, including those with even the most advanced stages of disease," Laird and colleagues wrote.

Their conclusion was echoed in an accompanying editorial by Michael Jaff, DO, of Massachusetts General Hospital in Boston. "It is exciting to learn through this retrospective single-center propensity analysis that aggressive statin therapy may not only reduce myocardial infarction, stroke, and death, but may actually improve limb survival in the most advanced PAD patients," he wrote.

What was disappointing, Jaff indicated, was that only 65% of the study sample were taking statins, even though published guidelines call for statins to be prescribed routinely for PAD patients.

For the current study, Laird and colleagues analyzed data in a registry of PAD patients maintained at the University of California Davis from 2006 to 2012. Of these, records for 380 indicated at least one presentation of critical limb ischemia with angiography with or without endovascular treatment. Median follow-up for outcomes after procedures was 409 days.

Patients were categorized as statin users when either hospitalization records or the most recent visit before undergoing the procedure showed current statin use. Among statin users, the most common types were simvastatin (Zocor) and atorvastatin (Lipitor).

Mean patient age was about 69 (SD 13). Significantly more patients taking statins had diabetes, hypertension, coronary artery disease, and a history of MI or carotid stenosis (allP<0.001), compared with nonusers. A history of stroke was also more common in the statin users (P=0.01).

Low-density lipoprotein and total cholesterol levels were significantly lower on average in the statin users, despite the increased comorbidity burden (LDL, 75 versus 96 mg/dL, P<0.001; total cholesterol, 142 versus 167 mg/dL, P=0.001).

Crude 1-year post-procedure rates of MI, stroke, all-cause mortality, and amputation were as follows in the two groups:

MI: statin users 5%, nonusers 6% (P=0.2)

Stroke: statin users 1%, nonusers 3% (P=0.1)

Death: statin users 15%, nonusers 21% (P=0.04)

Composite of the above: statin users 18%, nonusers 23% (P=0.048)

Amputation: statin users 12%, nonusers 18% (P=0.3)

The researchers also found that, among the statin users, those with LDL levels higher than 130 mg/dL had significantly higher event rates than those with lower levels. "Future studies should continue to investigate the optimal target level of LDL among this high-risk group of patients," they wrote.

Laird and colleagues also examined lesion outcomes in a subgroup of 295 patients undergoing endovascular interventions. In general, statin users were more likely to achieve primary assisted or secondary patency both in femoropopliteal and infrapopliteal lesions, although statistical significance was achieved only for the latter category (P<0.05).

Limitations to the study included its restriction to a single center and the possibility of unmeasured confounders. Laird and colleagues noted that statin use might be "a marker for quality of or access to care." Also, the duration of statin use and patients' adherence was not assessed.

Source: www.medpagetoday.com