The association between sclerostin and incident type 2 diabetes risk: a cohort study.

OBJECTIVE: To determine whether sclerostin is associated with fasting glucose, insulin levels, insulin resistance or increased risk of incident type 2 diabetes.

BACKGROUND: Type 2 diabetic patients have a higher risk of fractures. Recent studies suggest sclerostin, a regulator of osteoblast activity, is associated with diabetes.

MATERIALS AND METHODS: Sclerostin levels were obtained from 1778 individuals with no history of type 2 diabetes participating in the population-based Canadian Multicentre Osteoporosis Study (CaMos) cohort. Participants were followed until diagnosis of type 2 diabetes, death or end of the study period (31 December 2013). The relationship of sclerostin with fasting glucose, insulin levels and homoeostatic model assessment-insulin resistance (HOMA-IR) was studied in linear regression models. Cox proportional hazards models were used to determine the association of sclerostin levels and the risk of incident type 2 diabetes during a mean 7·5 years of follow-up.

RESULTS: Fasting glucose, fasting insulin levels and HOMA-IR were weakly correlated with sclerostin levels (Spearman's correlation coefficient: 0·11, P < 0·05; -0·09, P < 0·05; and -0·07, P = 0·02, respectively). Multiple linear regression analyses confirmed a significant association between sclerostin and fasting insulin and HOMA-IR but no significant association with fasting glucose levels. Sclerostin levels were not found to be significantly associated with the risk of incident type 2 diabetes (HR: 1·30; 95% CI: 0·37-4·57).

CONCLUSIONS: We observed an association between sclerostin levels with fasting insulin levels and HOMA-IR, but there was no clear association with type 2 diabetes risk. Further studies are needed to understand the role of sclerostin in type 2 diabetes.