Avaliação do complexo íntima-média da carótida pela ultrassonografia e sua relação com o escore Pathobiological Determinants of Atherosclerosis in Youth

Abstract

Atherosclerosis begins in childhood and adolescence and results in mortality or high-morbidity conditions such as myocardial infarction, cerebrovascular accident and peripheral artery disease. In order to identify individuals with a high probability of developing cardiovascular disease, risk scores for cardiovascular risk stratification were developed. In adolescence, the Pathobiological Determinants of Atherosclerosis in Youth score is used, but not much in Brazil. The thickening of the intima-media complex of the carotid artery, as assessed by ultrasonography, is regarded as diagnostic of subclinical atherosclerotic disease. However, there is no consensus in the literature on a cutoff to consider the presence of this condition. The goal of this study was to evaluate the prevalence of thickening of intima-media complex of the carotid, by means of the 75th percentile and Z-score, on high school adolescents and its relationship to the PDAY score. METHOD: Cross-sectional, quantitative study conducted in public high schools in Campina Grande, Paraíba, Brazil, from September 2012 to June 2013, involving 512 adolescents between 15 and 19 years of age. Sociodemographic (age, gender, skin color, socioeconomic status and maternal education); clinical,

anthropometric,

biochemical and behavioral variables, which comprise the PDAY score (fasting glucose, HbA1c, HDL and N-HDL cholesterol, blood pressure, BMI, and smoking), were evaluated. The thickening of the intima-media complex of the carotid artery was measured by ultrasound examination, with two cutoff points adopted: greater than or equal to 75th percentile values and greater than or equal to Z-score 2+. To evaluate the association between the thickening of intima-media complex of the carotid and socio-demographic, clinical, anthropometric, biochemical, and the PDAY score, the chi-square test was performed. To verify the independent association of each characteristic with the presence or absence of thickening of the intima-media layer, considered a dichotomous dependent variable, and the independent variables (components of the PDAY score, smoking and nutritional status score) a multivariate logistic regression model was developed. Analyses were performed in SPSS 22.0 and the significance level of 5% was considered. RESULTS: The thickening of the carotid artery was present in 25.0% when the 75th percentile cutoff was used, and 4.3% when the Z-score was used, and high cardiovascular risk was observed in 10.1% of the adolescents studied. Regardless of the criteria utilized, there was no association between carotid thickness and sex (p> 0.05). When assessed by percentile, there was only an association with one of its components, BMI> 30 (p= 0.005). On the other hand, the elevated measurements of intima-media complex of the carotid, using the Z-score, were associated with elevated systolic blood pressure (p= 0.024), high non-HDL cholesterol (p= 0.039) and those with a PDAY score classified as high risk (p= 0.003). After adjusting the model, high PDAY score proved to be an independent risk factor for the presence of thickening of the carotid artery, with a 4 times greater chance of having this condition when compared with those at low risk. CONCLUSION: The evaluation of thickening of intima-media complex of carotid by ultrasonography, using as a cutoff Z-score, was associated with the Pathobiological Determinants of Atherosclerosis in Youth score.