High plasma levels of diacylglycerols, triacylglycerols up risk of incident T2D

Increased plasma levels of diacylglycerols (DAGs) and triacylglycerols (TAGs) appear to increase the risk of incident type 2 diabetes (T2D), according to a study among Chinese. Liver fat accumulation may partially explain such associations.

“Few lipidomic studies have specifically investigated the association of circulating glycerolipids and T2D risk, especially among Asian populations,” the authors said. “It remains unknown whether or to what degree fatty liver could explain the associations between glycerolipids and T2D.”

In this prospective cohort study with 6 years of follow-up, the relationship between plasma glycerolipids and incident T2D was examined and the potential role of liver fat accumulation in the associations explored. A total of 1,781 Chinese participants aged 50–70 years were included. Incident T2D was the main outcome measure.

Of the participants, 463 developed T2D at the 6-year resurvey. After multivariate adjustment for conventional risk factors, 43 of 104 glycerolipids significantly correlated with incident T2D at the false discovery rate of 5 percent.

Further adjustment for glycated haemoglobin revealed that nine of the 43 glycerolipids remained significant: two DAGs (16:1/20:4, 18:2/20:5) and seven TAGs (46:1, 48:0, 48:1, 50:0, 50:1, 50:2, and 52:2). Relative risks (RRs) ranged from 1.16 (95 percent confidence interval [CI], 1.05–1.27) to 1.23 (95 percent CI, 1.11–1.36) per standard deviation increment of glycerolipids.

Additional adjustment for fatty liver index, however, greatly offset these associations (RR, 0.88, 95 percent CI, 0.81–0.95 to RR, 1.10, 95 percent CI, 1.01–1.21).

In mediation analyses, fatty liver index explained 12 percent to 28 percent of the associations between glycerolipids and T2D (p<0.01 for all).