Serum sclerostin and bone turnover in latent autoimmune diabetes in adults

Purpose: Bone formation is impaired in both type 1 and type 2 diabetes (T2D) while sclerostin, an antagonist of bone formation, is increased in T2D only. No data are available on latent autoimmune diabetes in adults (LADA), an autoimmune type of diabetes that may clinically resemble T2D at diagnosis. We evaluated serum sclerostin and bone turnover markers in LADA compared with T2D, and whether sclerostin is affected by metabolic syndrome (MetS) in T2D or LADA.; Methods: This cross-sectional study included 98 T2D and 89 LADA patients from the Action LADA and NIRAD cohorts. Patients were further divided according to MetS status. Non-diabetic subjects (n=53) were used as controls. Serum sclerostin, bone formation (P1NP) and bone resorption (CTX) were analyzed.; Results: T2D subjects had higher sclerostin than LADA (p=0.0008, adjusted for sex and BMI), even when analysis was restricted to MetS subjects (adjusted p=0.03). Analyzing T2D and LADA separately, sclerostin was similar between subjects with and without MetS, However, a positive trend between sclerostin and number of MetS features was seen in T2D (p for trend=0.001) but not in LADA. Subjects with either T2D or LADA had lower CTX than controls (p=0.0003), and not significantly reduced P1NP. Sclerostin was unrelated to age or HbA1c, but correlated with BMI (rho=0.29; p=0.0001), HDL (rho=-0.23; p=0.003), triglycerides (rho=0.19; p=0.002) and time since diagnosis (rho=0.32, p<0.0001).; Conclusions: LADA patients present lower bone resorption compared to controls, similarly to T2D. Sclerostin is increased in T2D but not in LADA suggesting possible roles on bone metabolism in T2D only.