Plasma Ceramides containing Saturated Fatty Acids are Associated with Risk of Type 2 Diabetes.

Abstract Recent studies suggest that the type of saturated fatty acid bound to sphingolipids influences the biological activity of those sphingolipids. However, it is unknown whether associations of sphingolipids with diabetes may differ by the identity of bound lipid species. Here we investigated associations of 15 ceramide and sphingomyelin species (i.e., all sphingolipids, measured with coefficient of variation less than 20%) with incident type 2 diabetes in the Cardiovascular Health Study (n = 3,645), a large cohort study of cardiovascular disease (CVD) among elderly adults who were followed from 1989-2015. Diabetes incidence was defined as fasting glucose ≥126 mg/dL or non-fasting glucose ≥200 mg/dL; reported use of insulin or oral hypoglycemic medication; or documentation of diabetes diagnosis through the Centers for Medicare and Medicaid Services records. Associations of each sphingolipid with incident diabetes were assessed using a Cox proportional hazards regression model. We found that higher circulating levels of ceramide with acylated palmitic acid (Cer-16), stearic acid containing ceramide (Cer-18), arachidic acid containing ceramide (Cer-20), and behenic acid containing ceramide (Cer-22) were each associated with a higher risk of diabetes. The hazard ratios for incident diabetes per 1 SD higher log levels of each ceramide species were: 1.21 (95% CI 1.09-1.34) for Cer-16, 1.23 (95% CI 1.10-1.37) for Cer-18, 1.14 (95% CI 1.02-1.26) for Cer-20, and 1.18 (95% CI 1.06-1.32) for Cer-22. In conclusion, higher levels of Cer-16, Cer-18, Cer-20, and Cer-22 were associated with a higher risk of diabetes.