The Prevalence of Steatohepatitis Declines with Age in Non-urban Individuals with Obesity

Background: Worldwide, the prevalence of the major health disorder, obesity, has risen. Obesity is a risk factor for development of steatohepatitis, a precursor to chronic liver disease. Alanine transaminase (ALT) is a recognized marker for steatohepatitis. The prevalence of steatohepatitis in aging populations with obesity has not been well delineated. Objective: Our hypothesis is that the prevalence of steatohepatitis would be lower in older subjects with obesity due to the increased morbidity and mortality related to chronic liver disease in individuals with obesity. Method: Consecutive individuals with obesity (n=400) have been evaluated in gastrointestinal clinic. Exclusions (n=72) include cirrhosis, hepatitis C, Celiac disease, >28 g/day alcohol, and >2 g/day acetaminophen. Definition of elevation of ALT in men and women is based on the American College of Gastroenterology guidelines. Result: Among 328 eligible subjects, 175 are ≤ 64 years-old and 153 are ≥ 65 years old. Mean body mass index (BMI) of individuals ≤ 64 years is 36.0+/-5.2 kg/m<sup>2</sup> and mean BMI of individuals ≥ 65 years is 34.9+/-4.1 kg/m<sup>2 </sup>(t-test: p=0.036). Subjects with type 2 diabetes mellitus include 53 of 175 subjects ≤ 64 years and 94 of 153 subjects ≥ 65 years (Chi-square 2X2 Statistic: p<.001). The overall prevalence of ALT elevation is 47%. A Chi-square 2X2 statistic (p<.001) supports the hypothesis that ALT elevation is inversely dependent upon age, and a Chi-square 2X2 statistic (p=0.039) supports a higher prevalence of steatotic liver disease in younger subjects. Conclusion: The high prevalence of ALT elevation, consistent with steatohepatitis, in this non-urban population is statistically more common in subjects ≤ 64 years-old, supporting our hypothesis. This difference is not explained by type 2 diabetes, which is statistically more common in subjects ≥ 65 years-old, but is consistent with the higher prevalence of steatotic liver disease in subjects ≤ 64 years-old. The association between a higher prevalence of elevated ALT levels and a higher prevalence of hepatic steatosis supports the importance of weight loss to resolve hepatic steatosis in order to protect younger individuals with steatohepatitis.