SAN DIEGO — Adult patients with type 2 diabetes and severe vitamin D deficiency face a twofold increased risk of all-cause mortality, independent of urinary albumin excretion rate and conventional cardiovascular risk factors, results from a long-term observational study showed.
”A lot of people have insufficient levels of vitamin D without even knowing it,” Dr. Christel Joergensen, lead author, said in an interview during a poster session at the annual meeting of the American Society of Nephrology.
Dr. Joergensen of the Steno Diabetes Center, Gentofte, Denmark, and her associates followed 290 white patients with type 2 diabetes for a median of 15.5 years.
They defined severe vitamin D deficiency as the lower 10th percentile (below 13.9 nmol/L, corresponding to 34.7 ng/mL).
At baseline, patients' mean age was 54 years, 173 were normoalbuminuric, 73 had microalbuminuria, and 44 had macroalbuminuria. The median vitamin D level was 35.7 nmol/L.
During follow-up, 142 patients (49%) died. Of these, 102 (73%) died from cardiovascular causes. All-cause mortality was significantly increased in patients with severe vitamin D deficiency, an association that persisted after adjustment for urinary albumin excretion rate, glomerular filtration rate, hemoglobin A1c, and conventional cardiovascular risk factors.
Severe vitamin D deficiency was also significantly associated with cardiovascular mortality.
Dr. Joergensen cited the small number of patients as a study limitation. She had no financial conflicts to disclose.