Objective: To investigate whether administration of sodium fluoride (NaF) in addition to cyclical etidronate has a positive effect on bone mineral density (BMD) in patients with established osteoporosis during continued treatment with corticosteroids.
Patients and methods: 47 patients who were receiving treatment with corticosteroids were included in a two year randomised, double blind, placebo controlled trial. Established osteoporosis was defined as a history of a peripheral fracture or a vertebral deformity, or both, on a radiograph. All patients were treated with cyclical etidronate, calcium, and either NaF (25 twice daily) or placebo. Vitamin D was supplemented in the case of a low serum 25 (OH) vitamin D concentration. BMD of the lumbar spine and hips was measured at baseline and at 6, 12, 18, and 24 months.
Results: After two years of treatment, the BMD of the lumbar spine in the etidronate/NaF group had increased by +9.3% (95% confidence intervals (CI): +2.3% to +16.2%, p < 0.01), while the BMD in the etidronate/placebo group was unchanged: +0.3% (95% CI: -2.2% to +2.8%). The difference in the change in BMD between groups was +8.9% (95% CI: +1.9% to +16.0%, p < 0.01). For the hips, no significant changes in BMD were observed in the etidronate/NaF group after two years: -2.5% (95% CI: -6.8% to +1.8%); in the etidronate/placebo group BMD had significantly decreased: -4.0% (95% CI: -6.6% to -1.4%; p < 0.01). The difference between the groups was not significant: +1.5% (95% CI: -3.4% to +6.4%). No significant differences in number of vertebral deformities and peripheral fractures were observed between the two groups.
Conclusion: The effect of combination treatment with NaF and etidronate on the BMD of the lumbar spine in corticosteroid treated patients with established osteoporosis is superior to that of etidronate alone.