Sex-Specific Basal Metabolic Rate and NAFLD Risk: The Multi-Population Observational and Mendelian Randomization...

Area of Science:

• Metabolic Health
• Hepatology
• Genetics

Background:

• The relationship between basal metabolic rate (BMR) and non-alcoholic fatty liver disease (NAFLD) requires further elucidation, especially concerning sex-specific variations.
• Population-specific analyses are crucial for understanding BMR's impact on NAFLD prevalence.

Purpose of the Study:

• To investigate the association between BMR and NAFLD across different populations.
• To explore potential sex differences in the BMR-NAFLD relationship.
• To determine the causal link between BMR and NAFLD using genetic data.

Main Methods:

• Analysis of health examination data from 30,845 Chinese individuals and 5,019 US adults (NHANES 2017-2020).
• Estimation of BMR using the Mifflin-St Jeor equation and statistical analysis including logistic regression and restricted cubic splines (RCS).
• Two-sample Mendelian randomization (MR) study utilizing genome-wide association studies (GWAS) data for BMR and NAFLD in European populations.

Main Results:

• A significant, dose-dependent association between higher BMR quartiles and increased odds of NAFLD was observed in the Chinese population.
• Sex differences in BMR-NAFLD associations were significant in the Chinese cohort (P for interaction <0.05) but not in the US cohort.
• Two-sample MR confirmed a causal effect of BMR on NAFLD with an odds ratio (OR) of 1.59 (95% CI: 1.24-2.03).

Conclusions:

• Elevated BMR is an independent and causally relevant risk factor for NAFLD.
• The findings highlight population-specific sex differences in the BMR-NAFLD relationship, particularly in the Chinese population.
• These results suggest the potential need for tailored management strategies for NAFLD based on population and sex.