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Peripheral arterial disease (PAD) is widely accepted as an indicator disease for generalized atherosclerosis. As patients with symptomatic, but also asymptomatic PAD often present with coronary artery disease (CAD), the ankle brachial index may serve as a screening tool to detect CAD in primary care. We aimed to quantify the excess cardiovascular risk borne by PAD patients compared to those without PAD in a typical primary care sample of elderly patients. Methods. The German Epidemiological Trial on Ankle Brachial Index (getABI) is a large-scale prospective observational epidemiological 3-year study in 6,880 unselected patients ≥65 years in 344 representative offices across Germany. The prevalence in incidence of PAD (defined as ankle brachial index, ABI < 0.9) was determined with standardized Doppler sonography at baseline and regular follow-up intervals. Death including cardiac death and CAD events (myocardial infarction, coronary revascularisation) were reported by GPs and verified by hospital data (on-site monitored study). To determine relative risk elevations between patients with and without PAD, hazard rate ratios (HRR) were calculated using a multivariate Cox regression model adjusted for age, gender, body mass index and the known CAD risk factors smoking, diabetes, hypertension, lipid disorders, and previous CAD. Results. At baseline, mean age of patients was 72.5 yrs, 58% were females, 46% (ever) smoker, 74% had hypertension, 24% diabetes mellitus, and 52% lipid disorders. The prevalence of PAD in the cohort was 18.0% at baseline (35.5% when including distal arterial occlusions). At 3 years, the survival status of 6865 (99%) patients is known. All-cause mortality was 11.1% in patients with PAD and 4.2% in patients without PAD (adjusted HRR 1.9 [95% confidence interval: 1.5-2.3]). Mortality due to CAD was 4.5% vs. 1.1% (HRR: 2.7 [1.8-3.9]). Death due to other causes was also increased in PAD patients: 4.3% vs. 2.2% (HRR: 1.4 [1.0-2.0]). There was a clear inverse association between ABI and the incidence of (cardiovascular) deaths. For example, in patients with an ABI <0.5 all-cause mortality at 3 years was 25.0%, and cardiovascular mortality was 17.3%. Among the traditional risk factors, the presence of PAD (HRR 1.8 [1.5-2.3]) was second strongest predictor for mortality at 3 years, after current smoking (HRR 2.6 [1.9-3.6]).
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