philadelphia – Treatment with ergocalciferol (vitamin D2) normalized circulating 25-hydroxyvitamin D levels within 3 months in hemodialysis patients with 25-hydroxyvitamin D deficiency, but this did not translate to clinical benefit with respect to a number of measures in a 6-month randomized, double-blind, placebo-controlled trial.
Levels of 25-hydroxyvitamin D in 276 hemodialysis patients with vitamin D deficiency who were randomized to receive either ergocalciferol treatment for 6 months or placebo were 16.0 vs. 16.9 ng/ml at baseline, 41.0 vs. 17.3 ng/ml at 3 months, and 39.2 vs. 17.5 ng/ml at 6 months, respectively, Dr. Dana Miskulin reported at Kidney Week 2014.
Parathyroid hormone (PTH) level was the only measure that showed a significant difference between the placebo and treatment groups. PTH levels dropped with treatment at 6 months (decreasing from 475 pg/ml at baseline to 450 pg/ml), but levels rose in the placebo group (440 to 505 pg/ml). No significant differences were seen at 6 months between the two groups in the primary outcomes measure of Epoetin alfa (Epogen) dose (5,400 vs. 5,800 units per week at baseline and 6,100 vs. 7,000 units/week at 6 months in the groups, respectively). There also were no differences between the groups in calcium levels, phosphorus levels, C-reactive protein levels, 1,25-dihydroxyvitamin D dose, cinacalcet dose, infection rate, or all-cause or infection-related hospitalization, Dr. Miskulin of Tufts Medical Center, Boston said at the meeting, which was sponsored by the American Society of Nephrology.
Study participants had a mean age of 61 years, median dialysis vintage of 3.5 years, and 25-hydroxyvitamin D levels less than 30 ng/ml. A majority (60%) were back, 45% were women, and 46% had diabetes as the cause of end stage renal disease. The treatment and placebo groups were similar with respect to clinical factors at baseline.
Treatment was given at 50,000 IU weekly for 6 months in patients with 25-hydroxyvitamin D levels less than 16 ng/ml and 50,000 IU weekly for 3 months followed by 50,000 IU monthly for 3 months in those with levels of 16-30 ng/ml, she said.
Vitamin D deficiency has been linked to numerous health problems, including cardiovascular events and mortality, infections, immune disorders, diabetes, cancers, and skin diseases, and about 80% of dialysis patients have 25-hydroxyvitamin D levels less than 30 ng/ml, Dr. Miskulin said.
The current findings suggest that while supplementation with at least 50,000 units of ergocalciferol every 2 weeks achieves and maintains vitamin D levels greater than 30 ng/ml without hypercalcemia or hyperphosphatemia in most hemodialysis patients, the benefits of supplementation are questionable. Although she agreed that without clinical benefit there is no need to provide supplementation, she also acknowledged that longer follow-up is needed to determine the effects of vitamin D supplementation.
This study was funded by Dialysis Clinic, Inc. Dr. Miskulin reported having no disclosures.