Prevalence of peripheral arterial disease in type 2 diabetes mellitus and its correlation with coronary artery disease and its risk factors.

OBJECTIVES

Peripheral arterial disease (PAD) is one of the macrovascular complications of type 2 diabetes mellitus. Unlike other complications, it has received little attention in the Indian medical literature. There is significant difference in the reported prevalence of PAD and its associated risk factors between Indian and Western studies. In order to assess PAD in diabetics, its associated risk factors and its relationship with coronary artery disease, we conducted a hospital-based, cross-sectional study.

METHODS

Consecutive patients on regular follow up in our diabetes clinic were included. In addition to a detailed history and physical examination, anthropometric parameters like body mass index, waist circumference and waist hip ratio were measured. Relevant laboratory investigations were performed. Modified Rose questionnaire and Minnesota codes were used to diagnose coronary artery disease (CAD). Colour Doppler examination of the arteries of the lower limbs was performed. Arteries were evaluated both longitudinally and transversely. Individual ABI was obtained for each leg by dividing corresponding ankle pressure by the brachial pressure. The lower of the values obtained for the two legs was taken as the true ABI. A cut off of < 0.9 was used to define peripheral arterial disease. Predictors of PAD were assessed using univariate tests of significance. Binary logistic regression was used to identify independent predictors of CAD.

RESULTS

We studied 146 patients (79 men and 67 women; mean age 59.4 +/- 7.2 years; mean duration of diabetes 8.8 +/- 3.8 years). The prevalence of PAD was 14.4% with women having a slightly higher prevalence (14.9%), as compared to men (13.9%) (p=0.864). CAD was present in 28%. Age, duration of diabetes, smoking, systolic and diastolic blood pressures and an HbA1c >7% were significant predictors of PAD. We did not find a correlation between measures of obesity and PAD. Using binary logistic regression, older age (p=0.01), higher HbA1c levels (p=0.02), microalbuminuria (p=0.03) and deranged lipid profile (total cholesterol, HDL, triglycerides) were found to be significant predictors of CAD.

CONCLUSION

Using ankle brachial index, we found evidence of PAD in 14.3% of type 2 diabetics. Risk factors significantly associated with PAD were--higher age, longer duration of diabetes, higher systolic and diastolic blood pressure, smoking, higher HbA1c levels and CAD. The prevalence of CAD was higher in patients with PAD (52.38% vs. 24% in those without PAD; p=0.007). Thus the presence of PAD should alert the clinician to a high probability of underlying CAD.