Combined Effects of Lifestyle Risk Factors on Fatty Liver Index

Abstract

Background: Factors of lifestyle may have a major impact on liver-related morbidity and mortality.We examined independent and joint effects of lifestyle risk factors on fatty liver index (FLI), a biomarker of hepatic steatosis, in a population-based cross-sectional national health survey. Methods:The study included 12,368 participants (5,784 men, 6,584 women) aged 25-74 years.Quantitative estimates of alcohol use, smoking, adiposity and physical activity were used to establish a total score of risk factors, with higher scores indicating an unhealthier lifestyle. FLI was calculated based on an algorithm including body mass index, waist circumference, serum gammaglutamyltransferase and triglycerides. Results:The occurrence of FLI ≥ 60% indicating fatty liver increased from 2.4% in men with zero risk factors to 81.9% in those with a total risk score of 7-8 (p < 0.0005 for linear trend) and in women from 0% to 73.5% (p < 0.0005). The most striking individual impacts on the likelihood for FLI above 60% were observed for physical inactivity (p < 0.0005 for both genders) and alcohol consumption (p < 0.0005 for men). Interestingly, coffee consumption was also found to increase with increasing risk factor scores (p < 0.0005 for linear trend in both genders). Conclusions:The data indicates that unfavorable combinations of lifestyle risk factors lead to a high likelihood of hepatic steatosis. Use of FLI as a diagnostic tool may benefit the assessment of interventions aimed at maintaining a healthy lifestyle and prevention of liver-related morbidity. BackgroundExcessive alcohol use, smoking, and lack of physical activity are typical risk factors of lifestyle, which may contribute to adiposity, fatty deposition in the liver and increased all-cause mortality [1][2][3][4].Furthermore, several risk factors are often present concomitantly in the same individual [5,6]. Recent studies have concluded that simultaneous adherence to multiple healthy lifestyle factors could significantly prolong life expectancy suggesting substantial therapeutic implications for interventions focusing on basic lifestyle factors [1,7,8].In current societies, hepatic steatosis is a highly common manifestation of health problems driven by behavioral factors. Building of too much fat in the liver may lead to a wide variety of clinical