Randomised controlled trial of vitamin D supplementation in sarcoidosis

Objectives The role vitamin D intake/production plays in sarcoidosis-associated hypercalcaemia is uncertain. However, authoritative reviews have recommended avoiding sunlight exposure and vitamin D supplements, which might lead to adverse skeletal outcomes from vitamin D insufficiency. We investigated the effects of vitamin D supplementation on surrogate measures of skeletal health in patients with sarcoidosis and vitamin D insufficiency. Design Randomised, placebo-controlled trial. Setting Clinical research centre. Participants 27 normocalcaemic patients with sarcoidosis and 25-hydroxyvitamin D (25OHD) <50nmol/L. Intervention 50000IU weekly cholecalciferol for 4weeks, then 50000IU monthly for 11months or placebo. Primary and secondary outcome measures The primary endpoint was the change in serum calcium over 12months, and secondary endpoints included measurements of calcitropic hormones, bone turnover markers and bone mineral density (BMD). Results The mean age of participants was 57years and 70% were women. The mean (SD) screening 25OHD was 35 (12) and 38 (9) nmol/L in the treatment and control groups, respectively. Vitamin D supplementation increased 25OHD to 94nmol/L after 4weeks, 84nmol/L at 6months and 78nmol/L at 12months, while levels remained stable in the control group. 1,25-Dihydroxy vitamin D levels were significantly different between the groups at 4weeks, but not at 6 or 12months. There were no between-groups differences in albumin-adjusted serum calcium, 24h urine calcium, markers of bone turnover, parathyroid hormone or BMD over the trial. One participant developed significant hypercalcaemia after 6weeks (total cholecalciferol dose 250000IU). Conclusions In patients with sarcoidosis and 25OHD <50nmol/L, vitamin D supplements did not alter average serum calcium or urine calcium, but had no benefit on surrogate markers of skeletal health and caused one case of significant hypercalcaemia. Trial registration This trial is registered at the Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au). The registration number is ACTRN12607000364471, date of registration 5/7/2007.