Alanine aminotransferase elevation not associated with fatty liver is frequently seen in obese Japanese women

OBJECTIVE: To determine the prevalence of fatty liver and alanine aminotransferase (ALT) elevation in obese Japanese women and to clarify the factors contributing to fatty change and ALT elevation in the cohort. DESIGN: Cross-sectional and population-based study. SUBJECTS: From 4366 women who received their annual health check-up, 4211 women were selected for analysis. All 4211 women were negative for hepatitis virus markers. MEASUREMENTS: Peripheral blood cell counts, liver biochemical tests, fasting glucose, cholesterol and triglyceride levels, uric acids, glycosylate hemoglobin A1c, and ultrasound examination. RESULTS: Ultrasonographic evidence of fatty liver and ALT elevation was seen in 391 (9.3%) and 238 (5.7%), respectively, of the 4211 women. Frequencies of both fatty liver and ALT elevation increased with increase in the degree of obesity. The frequency of ALT elevation was higher in women with fatty liver than in women without fatty liver among the nonobese or mildly obese group. However, the frequency of ALT elevation was not significantly different between women with fatty liver and women without fatty liver among the severely obese group. Multivariate analysis showed that obesity, hemoglobin (> or = 14 g/dl), triglyceride (> or = 150 mg/dl), diabetes mellitus, and fatty liver were significant predictors of ALT elevation. However, only two variables, hemoglobin (> or = 14 g/dl) and presence of diabetes, were significant in the severely obese group. CONCLUSIONS: ALT elevation not associated with fatty liver was frequently seen in obese women, suggesting that obesity is directly associated with the elevated ALT level in Japanese obese women. In addition, hemoglobin (> or = 14 g/dl) was a strong predictor of ALT elevation in the severely obese group.