Peripheral artery disease is a coronary heart disease risk equivalent among both men and women: results from a nationwide study

Aims Lower extremity peripheral artery disease (PAD) has been proposed as a coronary heart disease (CHD) risk equivalent'. We aimed to examine whether PAD confers similar risk for mortality as incident myocardial infarction (MI) and whether risk differs by gender. Methods Using nationwide Danish administrative registries (2000-2008), we identified patients aged 40 years with incident PAD (PAD only, n=35,628), incident PAD with a history of MI (PAD+MI, n=7029), and incident MI alone (MI alone, n=71,115). Results Patients with PAD only tended to be younger, female, and have less comorbidity than the other groups. During follow up (median 1051 d, IQR 384-1938), we found that MI-alone patients had greater risk of adverse outcomes in the acute setting (first 90 d); however, the PAD-only and PAD+MI groups had higher long-term mortality at 7 years than those with MI alone (47.8 and 60.4 vs. 36.4%, respectively; p<0.0001). After adjustment, the PAD-only and PAD+MI groups had a higher long-term risk for mortality [hazard ratio (HR) 1.47, 95% confidence interval (CI) 1.44-1.51; and HR 1.65, 95% CI 1.58-1.72, respectively], cardiovascular mortality (HR 1.30, 95% CI 1.26-1.34; and HR 1.71, 95% CI 1.62-1.80, respectively), and composite of death, MI, and ischaemic stroke, 95% CI HR, 1.38, 95% CI 1.36-1.42; and HR 1.68, 95% CI 1.61-1.75, respectively). The greater long-term risks of PAD were seen for both women and men. Conclusions Both women and men with incident PAD have greater long-term risks of total and cardiovascular mortality vs. those with incident MI. PAD should be considered a CHD risk equivalent, warranting aggressive secondary prevention.