Relationship of serum Vitamin D concentrations with Adipokines and Cardiometabolic risk among non-Hispanic black type 2 diabetic and non-diabetic subjects: a cross-sectional study.

BACKGROUND: To report the association of serum 25-hydroxyvitamin D [25(OH)D] and its association with adipokines and cardiometabolic risk factors in Haitian Americans (HA) and African Americans (AA) by ethnicity and type 2 diabetes (T2D) status. METHODS: A cross-sectional study in 197 HA (92 with T2D and 102 without T2D) and 200 AA (97 with T2D and 103 without T2D) recruited in South Florida. Serum 25(OH)D concentrations and adipokines were analyzed by ELISA and cardiometabolic risk factors were indexed by obesity, glycemic control, insulin sensitivity, lipid profile, and blood pressure. RESULTS: Controlling for age, BMI, energy intake, smoking status and HOMA2-IR in multivariate linear regression analyses, serum 25(OH)D concentrations were significantly associated with WC (R(2) = 0.760, B = - 0.092, P = 0.027), HbA1C (R(2) = 0.142, B = - 0.012, P = 0.010), and TG (R(2) = 0.159, B = - 1.192, P = 0.003) in only HA without T2D. While serum 25(OH)D concentrations were significantly associated with TC (R(2) = 0.168, B = - 0.329, P = 0.040), log leptin (R(2) = 0.544, B = - 0.007, P = 0.021), and adiponectin (R(2) = 0.144, B = 0.111, P = 0.033), but slightly associated with LDL-c (R(2) = 0.133, B = - 0.278, P = 0.064) in only AA without T2D. Among individuals with T2D, serum 25(OH)D concentrations were marginally associated with IL-6 (R(2) = 0.109, B = 0.076, P = 0.085) in HA with T2D, and there was a trend toward significance with log leptin (R(2) = 0.393, B = - 0.006, P = 0.075) in AA with T2D in regression analysis. CONCLUSIONS: The findings that the associations of serum 25(OH)D concentrations with adipokines and cardiometabolic factors differ between HA and AA has clinical and public implications to guide design of T2D preventive strategies that are culturally specific even within the same ethnicity.