Treatment of postmenopausal osteoporosis with high doses of synthetic calcitriol. A randomized controlled study.
OBJECTIVE
To study the efficacy of synthetic 1,25 dihydroxyvitamin D3 (calcitriol) in the treatment of osteoporosis.


METHODS
Two-year, double-blind, randomized clinical trial.


METHODS
University medical center.


METHODS
Fifty postmenopausal women with vertebral fractures recruited by referral.


METHODS
Calcium intake was adjusted to 25 mmol/d (1000 mg/d) at baseline. Patients were then randomized to treatment with either calcitriol or placebo. During the study, calcium intake was reduced to 15 mmol/d (600 mg/d) and the dose of calcitriol was adjusted to maintain serum calcium less than 2.74 mmol/L (less than 11.0 mg/dL) or urine calcium less than 9.96 mmol/d (less than 400 mg/d).


RESULTS
After 2 years, the mean dose of calcitriol in the treated group was 0.62 micrograms/d. Bone mineral density of the spine increased 1.94% with calcitriol therapy and decreased 3.92% with placebo (P = 0.001). Total body calcium increased 0.21% with calcitriol therapy and decreased 1.85% with placebo (P = 0.004). Patients receiving placebo had significant decreases in spine density (P = 0.0007) and total body calcium (P = 0.0004). There were no differences in vertebral fracture rates between the groups. Renal function studies were not statistically different between the groups after 2 years.


CONCLUSIONS
The treatment of postmenopausal osteoporotic women with synthetic calcitriol for 2 years was associated with increases in spine density and total body calcium. No adverse effects on renal function were seen after long-term calcitriol therapy.
Gallagher
J C
JC
Bone Metabolism Unit, Creighton University Medical Center, Omaha, NE 68131.
Goldgar
D
D
D000368:Aged; D001706:Biopsy; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000473:pathology; D002117:Calcitriol / Q000008:administration & dosage* / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D005260:Female; D050723:Fractures, Bone / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology
D002117:Calcitriol