Vitamin D Status and Response to Daily 400 IU Vitamin D3 and Weekly Alendronate 70 mg in Men and Women with Osteoporosis
Annals of Pharmacotherapy, 05/12/2011
Karaplis AC et al. - About two thirds of patients previously diagnosed with osteoporosis have inadequate vitamin D status. A treatment regimen consisting of alendronate 70 mg/wk administered with daily vitamin D3 400 IU supplementation significantly increased patients' serum 25-(OH) D levels, but 47% did not achieve optimal levels. These results support both the National Osteoporosis Foundation and Osteoporosis Canada recommendations for higher vitamin D supplement doses (at least 800 IU daily) in osteoporotic patients receiving pharmacologic therapy for osteoporosis and for monitoring their serum 25-(OH) D response.Methods
- Prospective, single-cohort, open-label, multicenter study
- Community-dwelling men and postmenopausal women with osteoporosis were recruited at 197 sites across Canada.
- Patients received vitamin D3 400 IU/day supplementation coadministered with alendronate 70 mg/wk for 16 weeks.
- The primary outcome was the distribution of serum 25-(OH) D at baseline.
- Secondary outcome measures included changes from baseline in serum 25-(OH) D levels, adherence to study treatments, and incidence of treatment- related adverse events (AEs).
- Of the 681 patients included in the analysis, 485 (71.2%) completed the study.
- Patients were predominantly female (83.1%) with a mean (SD) age of 67.6 (10.7) years.
- At baseline, mean (SD) serum 25-(OH) D concentration was 25.4 (9.9) ng/mL and 68.0% of the patients had inadequate (less than 30 ng/mL) vitamin D status.
- At week 16, concentrations increased by 35.1% to 31.2 (9.2) ng/mL (p < 0.001) and the proportion of patients with inadequate 25-(OH) D levels was reduced to 47.0%.
- Adherence to the treatment regimen was high (greater than 95%).
- Gastrointestinal disorders were the most frequently reported (6.9%) treatment-related AEs.