Aims: Vitamin D deficiency is a major issue worldwide, and particularly in Middle Eastern countries where full body coverage is standard cultural practice. Epidemiology studies have suggested that vitamin D deficiency is associated with the development of type 2 diabetes. The relationship between diabetes complications and 1,25-dihydroxyvitamin D (1,25(OH)2D3), 25-hydroxyvitamin D3 (25(OH)D3), 24,25-dihydroxyvitamin D (24,25(OH)2D3) and 25-hydroxy-3epi-Vitamin D3 (3epi25(OH)D3) is unclear.

Methods: 750 Qatari subjects, 460 (61.3%) with type 2 diabetes and 290 (38.7%) nondiabetic, participated in the study. Plasma levels of vitamin D and its metabolites were measured by LC-MS/MS analysis.

Results: The type 2 diabetic subjects had lower levels of all vitamin D metabolites except 3epi25(OH)D3. Males had higher levels of all vitamin D metabolites (p < 0.001) versus females. In the type 2 diabetic subjects. 1,25OHD3 deficiency was associated with hypertension, diabetic retinopathy and coronary artery disease (p<0.01), whilst 25OHD3 and (24,25(OH)2D3) levels were only associated with dyslipidemia (p<0.005); 3epi25(OH)D3 was not associated with diabetic complications.

Conclusions: The active 1,25OHD3 correlated to diabetic complications, but 25OHD3 levels did not, other than for dyslipidemia. Vitamin D3 metabolites were lower in type 2 diabetic subjects in this Qatari population, where full body coverage is standard, particularly in Qatari females. The role of 24,25(OH)2D3 in dyslipidemia requires clarification, but 3epi25(OH)D3 appears not to be associated with diabetes complications.


S. Atkin: None. A.E. Butler: None.

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