Serum metabolite profile associated with incident type 2 diabetes in Koreans: findings from the Korean Genome and Epidemiology Study

The identification of metabolic alterations in type 2 diabetes (T2D) is useful for elucidating the pathophysiology of the disease and in classifying high-risk individuals. In this study, we prospectively examined the associations between serum metabolites and T2D risk in a Korean community-based cohort (the Ansan–Ansung cohort). Data were obtained from 1,939 participants with available metabolic profiles and without diabetes, cardiovascular disease, or cancer at baseline. The acylcarnitine, amino acid, amine, and phospholipid levels in fasting serum samples were analyzed by targeted metabolomics. During the 8-year follow-up period, we identified 282 cases of incident T2D. Of all metabolites measured, 22 were significantly associated with T2D risk. Specifically, serum levels of alanine, arginine, isoleucine, proline, tyrosine, valine, hexose and five phosphatidylcholine diacyls were positively associated with T2D risk, whereas lyso-phosphatidylcholine acyl C17:0 and C18:2 and other glycerophospholipids were negatively associated with T2D risk. The associated metabolites were further correlated with T2D-relevant risk factors such as insulin resistance and triglyceride indices. In addition, a healthier diet (as measured by the modified recommended food score) was independently associated with T2D risk. Alterations of metabolites such as amino acids and choline-containing phospholipids appear to be associated with T2D risk in Korean adults.