Association of vitamin D2 and D3 with type 2 diabetes complications

Abstract

Abstract Aims Vitamin D measurement is a composite of vitamin D 2 (25(OH)D 2 ) and D 3 (25(OH)D 3 ) levels, and its deficiency is associated with the development of type 2 diabetes (T2DM) and diabetic complications; vitamin D deficiency may be treated with vitamin D 2 supplements. This study was undertaken to determine if vitamin D 2 and D 3 levels differed between those with and without T2DM in this Middle Eastern population, and the relationship between diabetic microvascular complications and vitamin D 2 and vitamin D 3 levels in subjects with T2DM . Methods Four hundred ninety-six Qatari subjects, 274 with and 222 without T2DM participated in the study. Plasma levels of total vitamin D 2 and D 3 were measured by LC-MS/MS analysis. Results All subjects were taking vitamin D 2 and none were taking D 3 supplements. Vitamin D 2 levels were higher in diabetics, particularly in females, and higher levels were associated with hypertension and dyslipidemia in the diabetic subjects ( p < 0.001), but were not related to diabetic retinopathy or nephropathy. Vitamin D 3 levels measured in the same subjects were lower in diabetics, particularly in females ( p < 0.001), were unrelated to dyslipidemia or hypertension, but were associated with retinopathy ( p < 0.014). Neither vitamin D 2 nor vitamin D 3 were associated with neuropathy. For those subjects with hypertension, dyslipidemia, retinopathy or neuropathy, comparison of highest with lowest tertiles for vitamin D 2 and vitamin D 3 showed no difference. Conclusions In this Qatari cohort, vitamin D 2 was associated with hypertension and dyslipidemia, whilst vitamin D 3 levels were associated with diabetic retinopathy. Vitamin D 2 levels were higher, whilst vitamin D 3 were lower in diabetics and females, likely due to ingestion of vitamin D 2 supplements.