Vitamin D and Chronic Renal Insufficiency

Most patients with chronic renal insufficiency have vitamin D deficiency. It is still not common practice among nephrologists to monitor and correct vitamin D deficiency of chronic kidney disease (CKD) patients, because it is widely believed that any vitamin D deficiency associated with calcium-phosphate disturbances is better treated with activated vitamin D. However, correction of vitamin D deficiency with native vitamin D seems to have numerous favorable effects not only related to the renal and intestinal handling of calcium and phosphate. It may have beneficial effects on bone and vascular health, the immune system and physical performance that are not obtained with active vitamin D treatment. We are therefore planning a randomized, placebo-controlled, intervention study of 8 weeks' duration in which vitamin D3 supplementation (40 000 IE per week in one capsule) is compared with placebo in a trial including 120 CKD patients with vitamin D deficiency. Multiple biological variables are monitored in order to assess any effect on the biological systems of interest.