EFFECTS OF ORAL CALCITRIOL ON BONE-MINERAL DENSITY IN PATIENTS WITH END-STAGE RENAL-FAILURE

Evolution of bone mineral density (BMD) at various skeletal sites and the influence of calcitriol on BMD are still poorly documented in pati ents with terminal renal failure. Using dual photon absorptiometry, we investigated the changes in BMD at the levels of lumbar spine, femora l neck and midfemoral shaft in 21 patients with end-stage renal failur e (ESRF) treated with calcitriol (mean dosage +/- SEM: 0.21 +/- 0.02 m ug/day) and compared them to 25 patients with ESRF but not treated wit h calcitriol (control group) over a period of 20.3 +/- 1.5 and 17.2 +/ - 1.2 months, respectively. Lumbar spine BMD increased by 7.7 +/- 3.2% /year in the treated group and decreased by 2.5 +/- 1.3%/year in the c ontrol group (P < 0.005). Femoral shaft BMD increased more in treated than in control group (+6.7 +/- 2.3 vs. +1.4 +/- 2.0%/year; P < 0.05) and femoral neck BMD remained stable. PTH levels increased by 92 +/- 1 21 and 1033 +/- 254 pmol/year (P < 0.01) in the treated group and the controls, respectively. Osteocalcin changes were -2.7 +/- 3.7 and +20. 1 +/- 11.7 mug/liter (P < 0.05) per year in the same groups. These res ults indicate that low doses of oral calcitriol in patients with end-s tage renal failure were associated with an increase in BMD at the leve ls of lumbar spine and femoral shaft, and with a stabilization of seru m PTH and osteocalcin concentrations.