Hyperinsulinaemia: a risk factor for peripheral arterial disease in the non-diabetic general population

Peripheral arterial disease is a common complication of diabetes mellitus, and hyperinsulinaemia has been associated with an increased incidence of intermittent claudication in diabetic subjects. Our aim was to investigate the relationship between hyperinsulinaemia and peripheral arterial disease in the non-diabetic general population.

Eighty-three cases with peripheral disease and 88 age- and sex-matched controls were selected from non-diabetic participants in the Edinburgh Artery Study, a survey of 1,592 men and women aged 55-74 years of randomly selected from the general population.

Mean plasma insulin, 1 h after a 75 g oral glucose load, was higher in cases than in controls (73.6 versus 59.8 mU/l; P < 0.05). The relationship between insulin and disease was independent of blood pressure [odds ratio (OR) 2.04; 95% CI 1.11-3.74; P < or = 0.05] and partially independent of low- and high-density lipoprotein cholesterol and triglycerides (OR 1.86; 95% CI 0.99-3.48; P < or = 0.1). Mean 1 h insulin was higher in current or ex-smokers than in those who had never smoked (P < or = 0.05) and when smoking was added to the multivariate model, the relationship between insulin and disease diminished (OR 1.64; 95% CI 0.83-3.23; P > 0.1).

In the non-diabetic general population, peripheral arterial disease is associated with post-glucose hyperinsulinaemia, independently of blood pressure, lipoproteins and triglycerides. Some of this association may be mediated by a relationship between hyperinsulinaemia and smoking.