Gordura abdominal avaliada por ultrassom como preditor de diabetes mellitus gestacional

Abstract

The prevalence of gestational diabetes mellitus (GDM) has progressively increased, and the use of tools for early screening of GDM that combine safety, low cost, and high efficacy is of interest. We aimed to evaluate subcutaneous, visceral, and preperitoneal abdominal fat measured by ultrasound as a predictor of GDM; compare abdominal fat and maternal anthropometric measurements, and evaluate the association between increased blood glucose and large-for-gestational-age newborns. The total sample consisted of 352 pregnant women in the first (11 to 14 weeks) and second (20 to 24 weeks) trimesters who attended for routine ultrasound examination and who had normal first-trimester fasting glucose (less than 92 mg/dl). Second-trimester DMG status was obtained by oral glucose tolerance test (OGTT) with 75g glucose overdose. The total mean age of the participants was 33.3 (4.2) years. Data collection was performed from February 2019 to February 2020, with measurements of weight, height, circumferences (arm, calf, and thigh), skinfolds (bicipital, triceps, subscapular, and thigh), and abdominal fat measurements (visceral, subcutaneous, and maximal preperitoneal) by ultrasound. Statistical analyses were performed in the SPSS program version 20.0. A Receiver Operator Characteristic (ROC) curve determined the optimal threshold for predicting DMG. Intra-group differences were evaluated by paired t-Student or Wilcoxon test. Differences between weight and body mass index (BMI) were evaluated by the Friedman test. Pearson or Spearman correlations were performed between markers of the glycemic curve and body composition. The variances between body composition and the tertiles of the markers of the OGTT curve were evaluated by ANOVA or Kruskal Wallis test. The Bonferroni post hoc test was used to evaluate the differences between the groups. The statistical significance adopted was p <0.05. According to the ROC curve, a threshold of 45.25 mm of maximum preperitoneal fat was identified as the best cut-off point, with 87% sensitivity and 41% specificity to predict GDM. Crude and adjusted odds ratios (OR) for age and pre-pregnancy BMI were 0.730 (95% CI: 0.561 - 0.900) and 0.777 (95% CI: 0.623 - 0.931), respectively. In the second trimester of gestation, the increase in abdominal fat was proportional to the increase in basal glucose, by the Suzuki method (visceral fat p ≤ 0.051), Mauad (subcutaneous fat p ≤ 0.025), and Stoner (subcutaneous fat p ≤ 0.002). We observed, an increase in subcutaneous fat (p ≤ 0.029) and visceral fat (p ≤ 0.039), proportional to the increase in newborn weight assessed by the Suzuki method in the second trimester, but the differences were lost after adjustments. Also in the second trimester, we observed an increase in biceps (p ≤ 0.044) and subscapular (p ≤ 0.014) skinfolds that were proportional to the increase in glucose. It was concluded that maximum 11 preperitoneal fat, measured by ultrasound to predict the risk of GDM, appears to be a feasible, inexpensive, and practical alternative to incorporate into clinical practice during the first trimester of pregnancy.