Risk Factor Prevalence and their Relative Influence on Fatty Liver and Gallstone Disease: A Cross-Ethnic Study Comparing Two High-Risk Populations from Chile and Northeast Germany

Abstract

Objective: Fatty Liver Disease (FLD) and Gallstone disease (GSD) are among the most common gastrointestinal disorders worldwide. Based on data of two ethnically distant populations from Santiago de Chile and Northeast Germany sharing remarkably high prevalence for both diseases, we aimed to estimate (1) the standardised prevalence of FLD and GSD, (2) the population-specific prevalence of known risk factors and (3) the relative influence of each risk factor for the occurrence of the respective outcome.
Design: We used data from two population-based studies from Chile (n=742) and Germany (n=3632). Regression methods were applied to assess the prevalence of risk factors at a specific age. To quantify the relative contribution of the risk factors to the occurrence of FLD and GSD, we used hierarchical variation partitioning.
Results: The standardised prevalence of FLD ranged from 20.7% in Chilean men to 37.9% in German men and the standardised prevalence of GSD from 14.5% in German men to 40.5% in Chilean women. Risk profiles differed considerably between populations and sexes. Overall, the contributions of the risk factors to the occurrence of FLD and GSD coincided widely. For FLD, age and BMI were the predominant factors, followed by serum triglyceride levels and the Single-Nucleotide Polymorphism (SNP) rs738409 C>G of the PNPLA3 gene. In GSD age was the predominant determinant, in women additionally BMI. Alcohol consumption played a marked role in Chilean men, being positively associated with GSD, similarly the use of contraceptives in Chilean women. The relative contribution of the lithogenic SNP rs11887543 was low in both populations, with marginal effect in Chileans.
Conclusion: Despite marked differences in risk profiles, relative influences of risk factors coincided widely between study populations. Knowledge about importance of risk factors for fatty liver and gallstone disease may guide therapy and advises for lifestyle changes.