Association of nonalcoholic fatty liver disease with bone mineral density and serum osteocalcin levels in Korean men

OBJECTIVE Bone mineral density has been reported to negatively associate with nonalcoholic fatty liver disease. Osteocalcin, a bone formation marker and metabolic regulator, has been previously evaluated as the mediator between bone mineral density and nonalcoholic fatty liver disease. Herein, we aimed to investigate the correlations of nonalcoholic fatty liver disease with bone mineral density and serum osteocalcin levels in Korean men. METHODS A total of 859 men (249 and 610 men with and without nonalcoholic fatty liver disease, respectively) were recruited for this retrospective cross-sectional study. All participants underwent hepatic ultrasonography and dual energy X-ray absorptiometry. Anthropometric and biochemical data, including the serum osteocalcin levels and homeostasis model assessment of insulin resistance (HOMA-IR), were collected. RESULTS Nonalcoholic fatty liver disease negatively associated with right-hip bone mineral density (odds ratio, 0.797; 95% confidence interval, 0.645-0.984; P=0.035) and serum osteocalcin (odds ratio, 0.948; 95% confidence interval, 0.910-0.988; P=0.011) after adjusting for BMI and HOMA-IR. The mean right-hip bone mineral density was lower in men with versus without nonalcoholic fatty liver disease after adjusting for serum osteocalcin, BMI and HOMA-IR (0.11±0.06 vs. 0.29±0.04; P=0.019). CONCLUSION Nonalcoholic fatty liver disease negatively associated with right-hip bone mineral density and serum osteocalcin in Korean men. General population-based prospective studies evaluating the causal relationship between bone metabolism and nonalcoholic fatty liver disease are needed, and the mechanism linking nonalcoholic fatty liver disease to bone mineral density beyond insulin resistance and osteocalcin should be evaluated in the future.