Osteoporosis in inflammatory bowel disease: effect of calcium and vitamin D with or without fluoride.

Background: Previous data have indicated low bone formation as a mechanism of osteoporosis in inflammatory bowel disease. Fluoride can stimulate bone formation.
Aim: To assess the effect of fluoride supplementation on lumbar spine bone mineral density in osteoporotic patients with inflammatory bowel disease treated in parallel with calcium and vitamin D.
Methods: In this prospective, randomized, double-blind, parallel and placebo-controlled study, 94 patients with inflammatory bowel disease (lumbar spine T score below - 2 standard deviations, normal serum 25OH vitamin D), with a median age of 35 years, were included. Bone mineral density was measured by dual-energy X-ray absorptiometry. Patients were randomized to receive daily either sodium monofluorophosphate (150 mg, n=45) or placebo (n=49) for 1 year, and all received calcium (1 g) and vitamin D (800 IU). The relative change in bone mineral density from 0 to 12 months was tested in each group (fluoride or placebo) and compared between the groups.
Results: Lumbar spine bone mineral density increased significantly in both groups after 1 year: 4.8 +/- 5.6% (n=29) and 3.2 +/- 3.8% (n=31) in the calcium-vitamin D-fluoride and calcium-vitamin D-placebo groups, respectively (P < 0.001 for each group). There was no difference between the groups (P=0.403). Similar results were observed according to corticosteroid intake or disease activity.
Conclusions: Calcium and vitamin D seem to increase lumbar spine density in osteoporotic patients with inflammatory bowel disease; fluoride does not provide further benefit.