Effects of long-term risedronate treatment on serum ferritin levels in postmenopausal women with osteoporosis: the impact of cardiovascular risk factor load.

OBJECTIVE: Although ferritin has been considered as a possible link between accelerated bone loss and atherosclerosis, the long-term impact of therapeutic agents widely used to treat osteoporosis, such as bisphosphonates, on ferritin levels has not been investigated. The present study investigated the effects of risedronate on serum ferritin levels in postmenopausal women with osteoporosis. METHODS: In an open-label, prospective, uncontrolled study, 68 postmenopausal women with osteoporosis were evaluated. Study participants received risedronate orally at a dose of 35 mg/week during a 6-month treatment period. Blood sampling for lipid profile, hemoglobin A1c, insulin, fibrinogen, C-reactive protein, osteoprotegerin, and ferritin was performed at baseline and after 6 months of treatment. Pulse-wave velocity and augmentation index at baseline were determined using SphygmoCor version 7.1 (AtCor Medical, Sydney, Australia). RESULTS: Mean (SD) serum ferritin decreased significantly from 62.1 (44.8) to 46.7 (29.4) µg/dL (P < 0.0001) during the treatment period. On multiple linear regression analysis, the significant predictors of Δferritin were pulse-wave velocity (P = 0.04; effect size, 0.188), C-reactive protein (P = 0.021; effect size, 0.043), insulin (P = 0.011; effect size, 0.100), and high-density lipoprotein cholesterol (P = 0.046; effect size, 0.132) at baseline. CONCLUSIONS: Risedronate treatment is associated with significantly decreased serum ferritin levels in postmenopausal women with osteoporosis and cardiovascular risk factors.