Elevated serum alanine transaminase in patients with type 1 or type 2 diabetes mellitus

Abstract

Background: The risk of chronic liver disease is higher in diabetics, and serum alanine transaminase (ALT) is a sensitive predictor of mortality from liver disease. Aim: To estimate the prevalence of elevated ALT in type 1 and type 2 diabetes, and identify possible risk factors. Methods: We identified all patients (n=2077) attending review between September 2002 and August 2003. We excluded those with no ALT measurement (n=73); those whose alcohol consumption was >14 units/ week (women) (n=276) or >21 units/week (men) (n=324); and those with a diagnosis of Maturity Onset Diabetes of the Young, secondary diabetes, gestational diabetes or uncertain type of diabetes (n=51). We calculated the prevalences of elevated ALT in both type 1 and type 2 diabetes patients, and compared the demographic, microvascular risk factors and current drug use between each group using multivariate logistic regression. Results: Of 1353 patients included, 836 (61.9%) had type 2 diabetes. Elevated ALT was found in 9.5% (95%CI 7.1-12.3%) of patients with type 1 diabetes, and 12.1% (95%CI 9.9-14.5%) of those with type 2 diabetes. The risk of elevated ALT in patients with type 2 diabetes increased with increasing body mass index (ptrend=0.04), and was lower in those taking insulin (OR 0.38, 95%CI 0.22-0.65). Discussion: The prevalence of elevated ALT is 3-4 times higher in patients with either type 1 or type 2 diabetes than in the general population. Further studies investigating the aetiology and mechanisms of this elevation may suggest appropriate early interventions. © 2006 Oxford University Press.