Seventy-three consecutive diabetic adults with symptomatic peripheral neuropathy were evaluated for the presence of cardiovascular autonomic neuropathy and electrocardiographic evidence of myocardial infarction (MI). Twenty-five (34.2%) patients demonstrated cardiovascular autonomic neuropathy, and ten (13.7%) patients had electrocardiographic evidence of MI. Of the ten MI identified, seven were asymptomatic (silent) by history. The incidence of silent MI was significantly higher (P less than .04) in patients with cardiovascular autonomic neuropathy. It is postulated that sudden death in diabetic patients with cardiovascular autonomic neuropathy may be due to silent MI.