Severe vitamin D deficiency independently predict all-cause mortality but not the development of microvascular complications in the eye and kidneys, according to a study published in Diabetes Care.
Low levels of vitamin D are highly prevalent worldwide and in several studies have been linked with type 2 diabetes and cardiometabolic disorders. Vitamin D levels have been shown to predict cardiovascular mortality in patients with type 2 diabetes.
Christel Joergensen, MD, of the Steno Diabetes Center in Gentofte, Denmark, and her colleagues measured plasma vitamin D levels in 227 patients with type 1 diabetes before the patients developed microalbuminuria. The median vitamin D level was 44.6 nmol/L. Vitamin D levels were not associated with age, gender, urinary albumin excretion rate, or blood pressure.
During follow-up, 44 patients (18%) died. In adjusted analyses, severe vitamin D deficiency was associated with a 2.7 times increased risk of death. Microalbuminuria developed in 82 patients (37%). Of these, 27 progressed to macroalbuminuria.
Background retinopathy developed in 192 of the 227 patients. Thirty-four patients (15%) progressed to proliferative retinopathy. Severe vitamin D deficiency at baseline did not predict development of these microvascular complications.
Dr. Joergensen’s group concluded that further studies are warranted to see whether vitamin D supplementation in type 1 diabetics who are deficient can improve their prognosis.