S Yuan et al, 2022. Lifestyle and metabolic factors for non-alcoholic fatty liver disease: Mendelian randomization study, European Journal of Epidemiology, published online.

May 30, 2022

ABSTRACT

The risk factors for nonalcoholic fatty liver disease (NAFLD) have not been clearly identified. We conducted a Mendelian randomization (MR) study to explore this. Independent genetic variants strongly associated with 5 lifestyle and 9 metabolic factors were selected as instrumental variables from corresponding genome-wide association studies (GWASs). Summary-level data for NAFLD were obtained from a GWAS meta-analysis of 8434 cases and 770,180 non-cases (discovery dataset) and another GWAS meta-analysis of 1483 cases and 17,781 non-cases (replication dataset). Univariable and multivariable MR analyses were performed. There were associations with NAFLD for lifetime smoking index (odds ratio (OR) 1.59, 95% confidence interval (CI) 1.31-1.93 per SD-increase), body mass index (BMI, OR 1.33, 95% CI 1.23-1.43 per SD-increase), waist circumference (OR 1.82; 95% CI 1.48-2.24 per SD-increase), type 2 diabetes (OR 1.21, 95% CI 1.15-1.27 per unit increase in log-transformed odds), systolic blood pressure (OR 1.17; 95% CI 1.07-1.26 per 10 mmHg increase), high-density lipoprotein cholesterol (OR 0.84, 95% CI 0.77-0.90 per SD-increase), and triglycerides (OR 1.23, 95% CI 1.15-1.33 per SD-increase). The associations for type 2 diabetes, systolic blood pressure, triglycerides, but not for high-density lipoprotein cholesterol remained strong after adjusting for genetically-predicted BMI. Genetic liability to type 2 diabetes mediated 51.4% (95% CI 13.4-89.3%) of the BMI-effects on NAFLD risk. There were suggestive inverse associations of genetically-predicted alcohol, coffee, and caffeine consumption, and vigorous physical activity with NAFLD risk. This study identified several lifestyle and metabolic factors that may be causally implicated in NAFLD.

NextPrevious

This information is intended for Healthcare professional audiences.
Please consider the environment before printing.