Objective: To conduct a cohort study of the effect of alcohol and obesity on liver enzymes in China.
Methods: To study 500 individuals of liver enzymes normality randomly in the 1999-year epidemiological survey, and liver enzyme levels (461 complete data) in 2006.
Results: Logistic-regression analysis showed a daily alcohol intake of at least 40 g, duration of drinking at least 10 years, and obesity, which were closely related to abnormality in liver enzyme levels; the relative risk (95% confidence interval) was 2.014 (1.108-3.662), 2.085 (1.106-3.928), and 1.772 (1.140-2.754), respectively (all P<0.05). According to the value of daily alcohol intake/duration of drinking and body mass index (BMI) to categorize, seven-year cumulative incidence of liver enzymes levels abnormality for the daily alcohol intake at least 40 g and obesity group or the duration of drinking at least 10 years and obesity group was the highest, 51.47 and 47.12%, respectively. No significant dose-response relationship was found between daily alcohol intake/duration of drinking and liver enzyme level abnormalities.
Conclusion: The risk of alcohol consumption and obesity-inducing liver injury together is far greater than the risk of a single factor inducing liver injury. An alcoholic threshold effect may be more important than a dose-response effect on liver enzyme levels.