Mineral metabolism disorders, vertebral fractures and aortic calcifications in stable kidney transplant recipients: The role of gender (EMITRAL study)

Background and objectives The relationship between mineral metabolism disorders, bone fractures and vascular calcifications in kidney transplant recipients has not been established. Method We performed a cross-sectional study in 727 stable recipients from 28 Spanish transplant clinics. Mineral metabolism parameters, the semi-quantification of vertebral fractures and abdominal aortic calcifications were determined centrally. Results Vitamin D deficiency (25OHD 3 <15 ng/ml) was more common in female recipients at CKD-T stages I–III (29.6% vs 44.4%; p = 0.003). The inverse and significant correlation between 25OHD 3 and PTH was gender-specific and women exhibited a steeper slope than men ( p = 0.01). Vertebral fractures (VFx) with deformity grade ≥2 were observed in 15% of recipients. Factors related to VFx differed by gender; in males, age (OR 1.04; 95% CI 1.01–1.06) and CsA treatment (OR: 3.2; 95% CI: 1.6–6.3); in females, age (OR 1.07; 95% CI: 1.03–1.12) and PTH levels (OR per 100 pg/ml increase: 1.27; 95% CI: 1.043–1.542). Abdominal aortic calcifications were common (67.2%) and related to classical risk factors but not to mineral metabolism parameters. Conclusions Vitamin D deficiency is more common among female kidney transplant recipients at earlier CKD-T stages, and it contributes to secondary hyperparathyroidism. Prevalent vertebral fractures are only related to high serum PTH levels in female recipients.