Prevalence of previously unrecognized peripheral arterial disease in patients undergoing coronary angiography

Coronary artery disease (CAD) and peripheral arterial disease (PAD) are serious manifestations of systemic atherosclerosis. A considerable proportion of patients with CAD have associated PAD; however, many are asymptomatic and this condition remains underdiagnosed. Little is known about the prevalence and clinical implication of PAD in patients undergoing coronary angiography in the Middle East with no history of the disease. To study the prevalence of previously unrecognized PAD of the lower limbs in patients undergoing coronary angiography, and to determine the correlation with CAD. This is a prospective study conducted at a university tertiary referral hospital. A total of 2120 patients referred for coronary angiography without a prior diagnosis of PAD, between January 1, 2014 and December 31, 2014, were included. Patients were evaluated through detailed medical history taking, a questionnaire survey to assess symptoms and functional status, ankle-brachial index (ABI) measurement, and coronary angiography. PAD was considered present if the ABI was <0.90 in either leg. In all patients, the prevalence of previously unrecognized PAD was 12.8%. There was no significant difference between men and women (13.4% vs 11.7%, P = .485). Abnormal angiographic results were seen in 82% (1739 of 2120). The prevalence of PAD was 14.7% in patients with abnormal coronary angiographic result, significantly higher than that in patients with normal results (4.5%, P < .0001). The prevalence of abnormal angiographic results among patients with and without PAD was 96% and 80%, respectively (P = .001). Factors independently related to PAD were age (odds ratio [OR] 1.081, 95% confidence interval [CI] 1.053–1.109; P < .001), hypertension (OR 3.122, 95% CI: 1.474–5.678; P < .004), diabetes (OR 1.827, 95% CI: 0.975–2.171; P = .04), smoking (OR 1.301, 95% CI: 0.725–2.076; P < .001), previous coronary artery bypass grafting (OR 2.939, 95% CI: 1.385–5.219; P = .004), previous cerebrovascular accident (OR 3.212, 95% CI: 1.872–9.658; P = .003), left main CAD (OR 9.535, 95% CI: 3.978–20.230; P = .002), and multivessel CAD (OR 1.869, 95% CI: 1.018–2.798; P = .03). Patients with CAD and PAD were associated with a higher prevalence of multivessel CAD (58.2% vs 42.6%, P < .005) and left main disease (3% vs 0.3%, P < .0001). The prevalence of undiagnosed PAD in patients undergoing coronary angiography was 12.8% (14.7% in patients with CAD) and associated with a higher incidence of cardiovascular risk factors, multivessel disease, and left main disease. The high prevalence of PAD in patients with CAD confirms the importance of active screening for PAD by using ABI. Routine determination of ABI in the clinical evaluation of all patients with CAD may help identify high-risk patients.