Cholecalciferol Lowers Albuminuria in Chronic Kidney Disease

In patients with chronic kidney disease (CKD), a daily oral cholecalciferol supplement reduces albuminuria—with the potential to delay the progressive decline in kidney function, reports a trial in Nephrology Dialysis Transplantation.

The prospective study included 101 CKD patients with albuminuria who were not receiving dialysis. Fifty of these patients had low 25(OH) vitamin D along with a high parathyroid level; this group received vitamin D supplementation with cholecalciferol, 666 IU/day. The remaining 51 patients were free of hyperparathyroidism and did not receive cholecalciferol, regardless of their vitamin D status. Changes in albuminuria were compared for the cholecalciferol and control groups.

The mean 25(OH)D level increased by 53 percent in the cholecalciferol group. After 6 months, the patients receiving cholecalciferol had a significant decrease in the urinary albumin-to-creatinine ratio (ACR): from 284 to 167 mg/g, compared with no change in untreated control individuals.

The drop in ACR was significantly correlated with the increase in 25(OH)D but was unrelated to other factors that could affect proteinuria. Cholecalciferol treatment was also associated with a decrease of 13.8 percent in mean parathyroid hormone level, with small increases in phosphate and calcium-phosphate product.

Previous reports had suggested that activation of the vitamin D receptor might have antiproteinuric effects. The new intervention study finds that six months of cholecalciferol treatment is associated with decreased albuminuria in CKD patients. The potential long-term effects on disease progression in this patient population await future trials [Molina P, et al. The effect of cholecalciferol for lowering albuminuria in chronic kidney disease: a prospective controlled study. Nephrol Dial Transplant 2013 [Epub ahead of print] doi: 10.1093/ndt/gft360.