Obesity Measures and Elevated Levels of Alanine Aminotransferase: A Population Based Study

Background: Obesity may lead to various morbidity including liver diseases. The present study was done to determine which obesity indices, including body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR), and waist to height ratio (WHtR) have the stronger association with rising levels of alanine aminotransferase (ALT). Materials and Methods: Of 6143 subjects aged ≥ 10 years of a cohort study in northern Iran, the data of 5052 subjects were analyzed. We performed multivariate logistic regression analyses for data of men and women, separately. In multivariate analyses the obesity measures were separately included in model in addition to other potential confounders. A high value of ALT was considered as outcome. The capability of obesity indices to discriminate an elevated level of ALT was evaluated using receiver operating characteristic (ROC). Results: Based on our results, men and women with obesity showed significantly higher values of liver enzymes for all obesity indices. In multivariate analysis, while WHtR showed the strongest association with a high value of ALT in men [Wald=91.44; OR=3.348, 95%CI (2.613-4.289); P<0.001], WC showed the strongest association in women [Wald=26.76; OR=1.724, 95%CI (1.402-2.119)]. Conclusion: WHtR in men and WC in women have more independent association with elevated levels of ALT.