Sleep apnoea is associated with major cardiac events in peripheral arterial disease

Obstructive sleep apnoea (OSA) is associated with atherosclerosis and cardiovascular events. Peripheral arterial disease (PAD) represents severe atherosclerosis with a high mortality after vascular surgery. The role of OSA in the prognosis of these patients is not yet established. 84 patients (aged 67 ± 9 years) scheduled for sub-inguinal surgical revascularisation were enrolled for preoperative polysomnography. The threshold for significant OSA was an apnoea/hypopnoea index ≥ 20 events·h(-1). Major adverse cardiovascular and cerebrovascular events (MACCE), including cardiac death, myocardial infarction, coronary revascularisation, angina pectoris requiring hospitalisation and stroke, were used as a combined end-point. During follow-up (median 52 months), 17 out of 39 patients with and six out of 45 patients without significant OSA suffered MACCE. In the multivariate Cox regression, the primary predictors of MACCE were significant OSA (hazard ratio (HR) 5.1 (95% CI 1.9-13.9); p=0.001) and pre-existing coronary artery disease (HR 4.4 (95% CI 1.8-10.6); p=0.001). Other significant predictors were a ≥ 4 year history of PAD (HR 3.8 (95% CI 1.3-11.5); p=0.02) and decreasing high-density lipoprotein/total cholesterol ratio (HR 0.95 per percentage (95% CI 0.90-1.00); p=0.048). OSA is associated with poor long-term outcome in patients with PAD following revascularisation. OSA might have an important role in the pathogenesis of cardiovascular morbidity and mortality in these patients.