Peripheral microvascular dysfunction as an independent predictor of atherosclerotic damage in type 1 diabetes patients: A preliminary study

Abstract

It has been recently hypothesized that peripheral microvascular dysfunction may contribute to atherosclerotic damage (AD) in diabetic patients. In order to test this hypothesis, we assessed forearm skin post-occlusive reactive hyperaemia (skin-PORH), an index of peripheral microvascular function, using laser-Doppler flowmetry, in 40 type 1 diabetes patients (T1D-pts), aged 49 ± 11 years, with no known cardiovascular complications, and in 50 age and sex-matched healthy control subjects (CS). T1D-pts also underwent carotid arteries ultrasound scanning (Ca-US) and ankle-brachial index (ABI) measurement. An arbitrary index of AD (AD-index), ranging from “0” (normal ABI, normal Ca-US) to “3” (abnormal ABI, one or more plaques at the Ca-US), was determined in T1D-pts. Linear and multiple regression analyses were performed to identify independent predictors of AD in T1D-pts. T1D-pts had a lower skin-PORH compared with CS (p = 0.015). In T1D-pts AD-index resulted to be negatively related with skin-PORH (R = 0.44; p < 0.005) or deep-breathing test (DBT) (R = 0.53; p < 0.0005), and positively related with systolic arterial pressure (R = 0.31; p < 0.05), microalbuminuria (R = 0.46; p < 0.005), patients' age (R = 0.51; p < 0.001) and diabetes duration (R = 0.39; p < 0.05). At the multiple regression analysis skin-PORH (R = 0.36; p < 0.005), patients' age R = 0.24; p < 0.05) and DBT (R = 0.4 – p < 0.005) resulted to be independent predictors of AD-index in T1D-pts. These preliminary findings support the hypothesis that peripheral microvascular dysfunction may contribute to AD in T1D-pts.