Associations between GDF15 levels and pre-diabetes in non-obese subjects

Growth differentiation factor 15 (GDF15) is a stress-response cytokine which belongs to the transforming growth factor β superfamily. Although GDF15 was initially found to have a role in metabolic diseases, the association between GDF15 and dysglycemic status remains inconclusive. Thus, the aim of this study was to examine the relationships between GDF15 and different glycemic statuses in non-obese subjects. We enrolled 502 non-obese subjects, among individuals who had normal glucose tolerance (NGT; n=125), isolated impaired fasting glucose (IFG; n=116), isolated impaired glucose tolerance (IGT; n=106), IFG plus IGT (n=27), and newly diagnosed diabetes (NDD; n=128). A multivariate linear regression analysis of GDF15 levels was used to find independent predictors. The median (IQR) GDF15 levels were 1641.0 (1187.0-1985.5) pg/mL, 1656.1 (1226.8-2379.7) pg/mL, 1487.8 (1145.9-1987.2) pg/mL, 1722.2 (1172.9-1939.0) pg/mL, and 2204.5 (1767.4-2919.1) pg/mL in NGT, IFG, IGT, IFG plus IGT, and NDD groups, respectively. The NDD group had significantly higher GDF15 levels than those with NGT, IFG, IGT, and IFG plus IGT. The IFG group had a significantly higher GDF15 value than the NGT group. In multivariate linear regression analysis, IFG (beta=0.145, 95% CI 192.487 to 740.937, p=0.001), NDD (beta=0.227, 95% CI 390.459 to 888.145, p<0.001), and high-sensitivity C reactive protein (beta=0.105, 95% CI 3.276 to 27.768, p=0.013) were independently associated with GDF15 levels. Non-obese subjects with isolated IFG and NDD had significantly higher GDF15 levels than those with NGT. In addition, A1C was independently associated with GDF15 levels. IFG and NDD, but not isolated IGT or IFG plus IGT, were positively associated with GDF15 levels.