Physical Activity Improves Borderline Ankle-Brachial Index Values in a Cardiovascular Risk Population

Peripheral arterial disease (PAD) is an underdiagnosed and undertreated disease because it remains asymptomatic for so long. The ankle-brachial index (ABI) is a valid method for detecting PAD in lower extremities. ABI ≤0.90 indicates incident PAD. Recent studies have found that subjects with borderline ABI values (0.91-1.00) have increased mortality rates. The objective of our 7-year follow-up study was to investigate the progression of PAD in borderline ABI subjects, who underwent a multifactorial cardiovascular intervention.

A total of 193 subjects with borderline ABI were examined in 2005-2006. None of them had previously diagnosed diabetes, cardiovascular or renal disease or intermittent claudication. They were given conventional treatment for multiple risk factors of cardiovascular diseases (hypertension, hypercholesterolemia, elevated blood glucose, smoking, and overweight). Sixty-four percent of these subjects (n = 123) attended a follow-up visit in 2012.

Of the 123 subjects with borderline ABI (mean age 59.0 ± 6.5 years, 62% female) at baseline, 18 (15%, 95% confidence intervals [CI]: 9%-22%) developed incident PAD during the follow-up. The mean ABI was 0.97 ± 0.03 at baseline and 1.01 ± 0.12 at 7-year follow-up visit. The change in mean ABI was +0.04 (95% CI: 0.03-0.07), P < 0.001. ABI improved significantly in 25 (20%) subjects. In multivariate ordered logistic regression analyses high and even moderate leisure-time physical activity (LTPA; odds ratio 6.15; 95% CI: 1.99-19.1) predicted a rise in ABI in comparison to low LTPA.

Physical activity seems to improve significantly ABI values among men and women with borderline ABI (0.91-1.00).