July - September 2006, Volume 2, Issue 3

Poiana C, Stoian L, Cucu C

One ear raloxifene treatment in osteoporotic postmenopausal women reduces bone turnover to premenopausal range

Acta Endo (Buc) 2006, 2 (3): 283-293
doi: 10.4183/aeb.2006.283

treatment of postmenopausal osteoporosis. It has estrogen agonist effects on bone and on surrogate markers of cardiovascular risk, but estrogen antagonist effects on breast and endometrium. It inhibits bone resorption and decreases bone turnover, increases bone mineral density and reduces the risk of vertebral fractures in postmenopausal women.\r\nObjectives: The main endpoint of our study was to evaluate the effect of raloxifene therapy (60 mg/day) on biochemical markers of bone turnover in romanian osteoporotic postmenopausal women. Secondary endpoints were the effect on bone mineral density (BMD), body mass composition and lipid profile.\r\nMaterials and methods: We performed a longitudinal, prospective, open study, investigating 29 postmenopausal white women with osteoporosis (Group 1) aged 56.9?7.8 years (mean ? SD) and in addition a control group of 29 premenopausal healthy white women (Group 2) with a mean age of 35.10 ? 7.8 years. The diagnosis of osteoporosis was established by dual-energy x-ray absorptiometry. We appreciated in both groups the bone turnover, measuring a marker of bone resorption: serum beta CrossLaps and a marker of bone formation: serum osteocalcin. We determined also the lipid profile: plasma cholesterol (mg/dL), HDL cholesterol (mg/dL), LDL cholesterol (mg/dL) and triglycerides (mg/dL) in all patients. Osteoporotic women received raloxifene 60 mg/day for one year. Biochemical bone markers, lipid profile and body composition have been evaluated at 3, 6 and 12 months of treatment and BMD was performed at 6 and 12 months of therapy.\r\nResults: Postmenopausal osteoporotic women showed an increased bone turnover in comparison with premenopausal women, with statistically significant increased serum values of both resorption and formation biochemical bone markers: respectively 0.48?0.2 vs 0.23?0.1 ng/mL for beta CrossLaps and 27.94?12.1 vs 17.30?8.9 ng/mL for osteocalcin, p<0.001. Raloxifene therapy for three months reduced significantly both bone resorption and formation: 0.36 ? 0.2 vs 0.48 ? 0.2 ng/mL, p< 0.005 for beta CrossLaps and 22.03 ? 10.1 vs 27.94 ?12.1 ng/mL, p< 0.001 for osteocalcin. After 3, 6 and 12 months of therapy with raloxifene the bone markers were statistically significant reduced: -21.2%, -20.4% and respectively -31.6% for osteocalcin and -25%, -39.6% and respectively -50% for beta CrossLaps (p< 0.01). After six months of therapy, serum levels of beta CrossLaps were reduced to premenopausal range (0.29 ? 0.1 vs. 0.23 ? 0.1 ng/mL, p=ns). Total cholesterol and LDL-C were reduced after 12 months (p< 0.03), with no increase in triglycerides and at the same time body mass composition was unchanged.\r\nConclusions: Our results suggest that raloxifene reduces as early as three months the bone turnover in postmenopausal osteoporosis. It reduces bone turnover in premenopausal range after only six months of therapy, for the bone resorption (beta CrossLaps) and after 12 months for bone formation (osteocalcin). In addition raloxifene treatment has favorable effects on BMD and lipid profile, proving safety and a stable body mass composition.

Keywords: bone markers, bone resorption, postmenopausal osteoporosis, raloxifene

Correspondence: Catalina Poiana, Endocrinology Department, &#8220;Carol Davila&#8221; University of Medicine and Pharmacy, 34-36 Bd. Aviatorilor, 011863, Bucharest, Romania, Tel/Fax; + 4021 317 7430, e-mail: endo.parhon@softnet.ro