Espessura da camada íntima-média da artéria carótida comum e idade vascular em pacientes com Diabetes Mellitus tipo 1

Abstract

Patients with type 1 diabetes mellitus (T1DM) have an early and diffuse preclinical atherosclerosis process. This process contributes to the high incidence of cardiovascular disease (CVD) found in this population. There are no recommendations for the identification and stratification of patients with T1DM and increased CVD risk. The measurement of the intima and media thickness (IMT) of the common carotid artery correlates with pre-clinical atherosclerosis and CVD risk. Identification of factors associated with the increase of IMT could contribute to the identification of those patients with higher CVD risk. Moreover, the estimation of "vascular age" (VA) using, could be a useful tool for the stratification of CVD risk. Objectives: evaluate the IMT of patients with T1DM compared to a group of individuals without diabetes. Identify clinical and laboratory factors associated with increased IMT and evaluate if the substitution of CA for the VA would be a useful tool to stratify the CVD risk of patients with T1DM. Methods: A cross-sectional study that evaluated 127 patients with T1DM and 125 control subjects. The IMT was measured using a semi-automated border detection software. VA was estimated in subjects with &#8805; 35 years old, using normality tables for IMT. Results: patients with T1DM had higher IMT compared to controls (p<0.001). Comparing T1DM patients and control subjects, women with T1DM had higher IMT difference (0.039) than men (0.033 mm). Age and diabetes duration had a synergistic effect on IMT in patients with T1DM. The gamma multivariate regression analysis in patients with T1DM showed that IMT was associated with age (Exp(β)=1.006, p<0.001), diabetes duration (Exp(β)=1.004, p=0.002), family history of type 2 diabetes (T2DM) (Exp(β)=1.048, p=0.014), Body mass index (BMI) (Exp(β)=1.006, p=0.008) creatinine clearance (Exp(β)=0.000, p=0.029) and total cholesterol (Exp(β)=0.999, p<0.001). In patients with T1DM there was a difference between VA and CA (9.4 years, p<0.001) and between CVD risk assessed by VA and by CA (3.8 %, p<0.001), without difference in the control group. Women with T1DM had higher difference between the VA and CA (11.2 years, p<0.001) than men with T1DM (6.4 years, p=0.021). In patients with T1DM there was a change in CVD risk stratification from low risk (8,8%) to a moderate risk (12,6%). There was an increase in the CVD risk stratification in 18 patients with T1DM (31%), 14 of then were female. There was a decrease os CVD risk from moderate do low risk in one male patient with T1DM. Discussion: patients with T1DM have increased carotid IMT, despite a young age. This IMT increase could be a precocious marker of CVD and it is even higher higher in women with T1DM and individuals with family history of T2DM. The VA may contribute to the evaluation of the "aging" of cardiovascular system and may be a useful tool for the identification and stratification of patients with increased CVD risk. Future prospective studies are needed to evaluate the causal relationship between carotid IMT and CVD and the reliability of VA for the prediction of CVD risk.