Injection of active vitamin D is associated with better survival of patients receiving chronic hemodialysis. Since in many countries oral active vitamin D administration is the most common form of treatment for secondary hyperparathyroidism we determined the survival benefit of oral active vitamin D in hemodialysis patients from six Latin America countries (FME Register as part of the CORES study) followed for a median of 16 months. Time-dependent Cox regression models, after adjustment for potential confounders, showed that the 7,203 patients who received oral active vitamin D had significant reductions in overall, cardiovascular, infectious and neoplastic mortality compared to the 8,801 patients that had not received vitamin D. Stratified analyses found a survival advantage in the group that had received oral active vitamin D in 36 of the 37 strata studied including that with the highest levels of serum calcium, phosphorus and parathyroid hormone. The survival benefit of oral active vitamin D was seen in those patients receiving mean daily doses of less than 1 microg with the highest reduction associated with the lowest dose. Our study shows that hemodialysis patients receiving oral active vitamin D had a survival advantage inversely related to the vitamin dose.
