Background: Non-alcoholic fatty liver disease is prevalent in affluent countries and is strongly associated with metabolic syndrome.
Aim: To study the prevalence of undiagnosed diabetes and postchallenge hyperglycaemia in Chinese patients with non-alcoholic fatty liver disease.
Methods: 73 consecutive patients with biopsy-proven non-alcoholic fatty liver disease and no history of diabetes underwent comprehensive metabolic screening. Diagnosis of diabetes and impaired glucose regulation was based on the 2006 American Diabetes Association criteria.
Results: The prevalence of undiagnosed diabetes and impaired glucose tolerance in non-alcoholic fatty liver disease patients was 33% and 29%, respectively. Among patients with 2-h plasma glucose above 7.8 mm, 47% had normal fasting glucose (below 5.6 mm). Impaired glucose tolerance was more common in patients with non-alcoholic steatohepatitis than those with simple hepatic steatosis (P = 0.036), and 2-h plasma glucose correlated with fibrosis stage (Spearman coefficient: 0.25, P = 0.046). In a binary logistic regression analysis, high fasting glucose and low high-density lipoprotein cholesterol were independent factors associated with diabetes. Nevertheless, if oral glucose tolerance test was only performed in non-alcoholic fatty liver disease patients with impaired fasting glucose, 20.8% of diabetes cases would be missed.
Conclusions: Isolated postchallenge hyperglycaemia is common among Chinese non-alcoholic fatty liver disease patients without history of diabetes. It is associated with histological severe disease, and cannot be accurately predicted by any fasting glucose cut-off.