Cardiovascular autonomic neuropathy in type 1 diabetic patients with and without peripheral neuropathy

One hundred Type 1 diabetic patients (54 men, 46 women) mean age 28.9+/-8.4 years, were selected from among individuals referred to our hospital, with no previous diagnosis of diabetic chronic complications including diabetic neuropathy. After clinical and physical examinations, subjects were divided into two groups: with (n = 37) and without (n = 63) peripheral neuropathy. The percentage of subjects with cardiovascular autonomic neuropathy (AN), diagnosed by positive results to at least two of the five cardiovascular tests (Valsalva ratio, EI ratio, 30/15 ratio, blood-pressure response to standing up and handgrip test), was 40%: 72.9% in the group with peripheral neuropathy and 20.6% in the group without peripheral neuropathy (P < 0.0001). The prevalence of cardiovascular AN was related to the duration of the diabetes (P < 0.0001) and to HbA1c (P < 0.02). The presence of microalbuminuria and the existence of retinopathy were higher (P < 0.01 ) in group 1 (with peripheral neuropathy). Logistic regression analysis showed that only the presence of higher excretion of albumin is independently related to the presence of peripheral neuropathy. In conclusion, cardiovascular AN is frequent in Type 1 diabetes; furthermore, prevalence increases with the existence of peripheral neuropathy and with duration of the diabetes.