Meta-Analysis Finds Risk of Disease Progression in PAD Is Higher Than Expected

January 13, 2016—A meta-analysis of mortality and disease progression in peripheral artery disease (PAD) found that the risk of disease progression is higher than expected. The study was published by Birgitta Sigvant, MD, et al online ahead of print in the European Journal of Vascular and Endovascular Surgery (EJVES).

As noted in EJVES, PAD affects up to 20% of older people and is associated with a high risk of cardiovascular (CV) morbidity but a rather low risk of progression of leg symptoms. However, these risk estimations are largely taken from cohort studies performed 20 years ago. The investigators systematically reviewed available data and attempted to perform meta-analyses of CV risk and disease progression.

The investigators conducted a database literature search from 1990 to 2015 using related subject headings. Inclusion criteria were cohort studies for PAD, sample size > 100 patients, follow-up ≥ 1 year, and studies presenting endpoints covering mortality and/or CV events. Analyses were performed for a reference population, as well as for groups with asymptomatic PAD, symptomatic PAD, and subjects with an ankle brachial index < 0.9.

Of 354 identified articles, 35 were eligible for systematic review. Sample size varied between 109 and 16,440 subjects. Mean age ranged from 56 to 81 years (standard deviation, 10.8), and mean follow-up was 6.3 years (range, 1–13 years). Most (91%) patients with symptomatic PAD had intermittent claudication (IC). 

Symptomatic PAD patients had higher 5-year cumulative CV mortality than the reference population (13% vs 5%). During follow-up, approximately 7% of asymptomatic PAD patients progressed to IC, and 21% of patients with IC were diagnosed as having critical limb ischemia, with 4% to 27% undergoing amputations, reported the investigators in EJVES.

The investigators concluded that the risk to the limb is underestimated in patients with PAD, whereas CV-related morbidity is more moderate than stated in the guidelines, especially for patients with IC. These findings should be considered when evaluating patients for treatment, advised the investigators.