Parathyroid Hormone Levels May Predict Nonalcoholic Steatohepatitis in Morbidly Obese Patients

BACKGROUND: Obesity as a worldwide health problem is associated with nonalcoholic steatohepatitis (NASH). Since severe liver injury may be present in asymptomatic obese patients and a definite diagnosis of nonalcoholic steatohepatitis can only be made after an invasive procedure of liver biopsy, there is a need for noninvasive methods to predict the probability of NASH. OBJECTIVES: To investigate the role of vitamin D endocrine system in predicting the probability of presence of NASH in asymptomatic morbidly obese candidates of bariatric surgery. PATIENTS AND METHODS: From December 09 to March 11, every patient undergoing bariatric surgery had a liver biopsy. Nonalcoholic steatohepatitis was diagnosed using the Lee’s criteria, the baseline labs obtained and the association between laboratory data and presence of NASH assessed. RESULTS: Forty-six patients (34 women, aged 36.5 ± 10.6 years) were analyzed. The mean levels of liver enzymes were significantly higher in the group with NASH (P value < 0.01). In an unadjusted logistic model, PTH was the only variable in vitamin D endocrine system which was significantly associated with NASH (odds ratio (OR): 1.04, 95%CI: 1.01 - 1.07). After adjustment for possible confounding factors, age (OR: 1.22, 95%CI: 1.00 - 1.50) and PTH (OR: 1.08, 95%CI: 1.01 - 1.16) were predictive factors for NASH (P value < 0.05). CONCLUSIONS: Elevated serum PTH level was the predictive factor for NASH in morbidly obese patients. Also, we reported elevated serum liver enzymes, high serum PTH levels and older age as predictors of NASH in patients seeking obesity surgical treatments.