A Positive Correlation of Basal Metabolic Rate With Significant Liver Fibrosis in Adults With MASLD and Obesity: Results From NHANES 2017–2020

Background and Aim Since the stage of liver fibrosis is closely associated with mortality in nonalcoholic fatty liver disease (NAFLD) and metabolic dysfunction–associated steatotic liver disease (MASLD), it is essential to identify patients at risk of fibrosis progression. Basal metabolic rate (BMR) has gained attention in weight management for individuals with obesity. This study aimed to assess the accuracy of BMR in predicting the severity of fibrosis in patients with NAFLD or MASLD. Methods Data from the National Health and Nutrition Examination Survey (NHANES) 2017–2020.03 were analyzed. Noninvasive diagnosis of liver steatosis was performed using the controlled attenuation parameter (CAP) measured by FibroScan. BMR calculated using the Harris–Benedict equation (BMRh) and the Mifflin–St Jeor equation (BMRm) was included in the analysis. Results A total of 4184 individuals with MASLD were included, of whom 639 (15.27%) had significant fibrosis. Among 1577 individuals with NAFLD, 223 (14.14%) had significant fibrosis. Participants with significant fibrosis were older and had higher CAP, BMRh, and BMRm values (all p < 0.05). Multivariate analysis identified BMR as an independent risk factor for significant fibrosis. In obesity participants with MASLD or NAFLD, both BMRh and BMRm were positively correlated with BMI, CAP, and liver stiffness measurement (all p < 0.01). For obesity participants with MASLD or NAFLD, both BMRh‐ or BMRm‐incorporating models had higher AUROCs than aspartate transaminase‐to‐platelet ratio index, fibrosis‐4, and gamma‐glutamyl transpeptidase to platelet ratio in predicting significant fibrosis (all p < 0.001). Conclusion BMR is elevated in individuals with NAFLD or MASLD and significant liver fibrosis. The novel model combining age, male gender, BMR, aspartate transaminase, white blood cell counts, platelet counts, and diabetes outperformed conventional noninvasive scoring systems in predicting significant fibrosis in individuals with MASLD and obesity.