Objectives: The metabolic syndrome has become a significant health problem worldwide. In this study, we investigated the relationship between the metabolic syndrome, bright liver (BL) by ultrasonography (US), and plasma alanine aminotransferase (ALT) levels among apparently healthy adults.
Research methods and procedures: A total of 15,430 nonalcoholic healthy adults without hepatitis B or C were recruited from four nationwide MJ Health Screening Centers in Taiwan in 2000. Metabolic syndrome was defined using the National Cholesterol Education Panel (NCEP) metabolic syndrome criteria or modified NCEP criteria. Based on liver US, subjects were classified into either having BL or not. The relationship between the metabolic syndrome, BL, and ALT levels was examined using multivariate logistic regression analysis.
Results: The crude OR of the metabolic syndrome was 13.92 (12.19 using modified NCEP criteria), and the age-BMI-sex-adjusted OR was 3.77 (3.71 using modified NCEP criteria) in subjects with BL vs. subjects without BL, respectively. The ORs of the metabolic syndrome were significantly higher in subjects with elevated ALT levels than in those with normal ALT levels. After adjustment for age, sex, and BMI, BL and elevated ALT level were independently associated with increased risk of the metabolic syndrome.
Discussion: Presence of BL and elevated plasma ALT level was independently associated with increased risk of the metabolic syndrome in adults. These factors contribute to a list of well-known risk factors, including obesity, aging, and male sex, and thus can be applied as an additional evaluation for the metabolic syndrome in a clinical setting.