Relationships between vertebral fractures, sex hormones and vitamin D in Moroccan postmenopausal women: a cross sectional study

BACKGROUND Vertebral Fractures (VFs) are associated with bone loss that occurs before menopause but is accelerated at menopause as a result of sex hormone deficiency. To determine the association of sex hormones, bone remodeling markers and vitamin D levels with bone mineral density (BMD) and asymptomatic VFs prevalence using vertebral fracture assessment (VFA) in a cohort of Moroccan menopausal women. METHODS This was a cross-sectional study conducted from October 2012 to April 2013 with menopausal women aged 50 years old and over. A total of 207 women who had no previous diagnosis of osteoporosis were enrolled in this cross-sectional study. Women were recruited prospectively from our laboratory department. VFA images and scans of the lumbar spine and proximal femur were obtained using a GE Healthcare Lunar Prodigy densitometer. VFs were defined using a combination of Genant semiquantitative approach and morphometry. Serum levels of estradiol, dehydroepiandrosterone sulfate, Sex hormone binding globulin, vitamin D, Osteocalcin, Crosslaps, intact parathormone were measured by Electrochemiluminescent immunoassay technique. RESULTS Among the 207 women, 18.3 % (n = 38) had densitometric osteoporosis. On VFA, VFs were detected in 134 (62.3 %), including 96 (44.6 %) grade 1 and 38 (17.6 %) grade 2/3. There was no difference in the plasma levels of sex steroids, bone remodeling markers and vitamin D in the group of women with VFs (grade 1 and grade 2/3) and without VFs. The combination of variables that best predicted grade 2/3 VFs included the number of years since menopause and the lumbar spine T-score. CONCLUSION These data confirm the importance of postmenopausal estrogen and SHBG concentrations in the bone loss and the pathogenesis of osteoporosis in elderly women, but not in the occurrence of the VFs.