OBJECTIVE: Although calcitriol is essential for bone healing, its serum concentrations are low after hip surgery, and they continue to decline during bone healing. This study aimed to test the hypothesis of an association of changes in calcitriol production with the status of fibroblast growth factor 23 (FGF23) and iron deficiency after elective hip replacement for coxarthrosis. METHODS: In this prospective study, we measured the biomarkers of 17 patients undergoing elective hip replacement on admission, on the first day after surgery, and at the regular check-up after 48 ± 8 days. The serum concentrations of 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, transferrin, ferritin, parathyroid hormone, intact plasma FGF23 (iFGF23) and C-terminal FGF23 (cFGF23) were determined. RESULTS: In our patients who underwent elective hip replacement, significant correlations existed between the percent change in the conversion rate of 25(OH)D to 1,25(OH)2D, plasma intact to C-terminal FGF23 ratio, and serum iron. CONCLUSIONS: The production of calcitriol is compromised after elective hip replacement surgery, leading to reduced levels of active vitamin D in the serum. Significant correlations between the percent change in the conversion rate of 25(OH)D to 1,25(OH)2D, plasma intact to C-terminal FGF23 ratio, and serum iron on the first day as well as 7 weeks after surgery could inspire future studies to determine whether and how calcitriol deficiency should be corrected, especially in fracture cases.

• Klíčová slova
• Calcitriol, Elective hip replacement, Fibroblast growth factor 23, Iron, Total 25 hydroxyvitamin D,
• MeSH
• fibroblastové růstové faktory * MeSH
• kalcitriol * MeSH
• lidé MeSH
• parathormon MeSH
• prospektivní studie MeSH
• vitamin D MeSH
• železo MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fibroblastové růstové faktory * MeSH
• kalcitriol * MeSH
• parathormon MeSH
• vitamin D MeSH
• železo MeSH

OBJECTIVE: To assess the decrease in serum calcitriol concentrations after hip fracture. METHODS: Serum concentrations of calcitriol, 25(OH)D, parathyroid hormone (PTH), directly measured free 25(OH)D, and indices of bone formation were measured in elderly patients with hip fracture (HF) and patients with elective hip replacement (EHR) at admission and after 7 weeks. RESULTS: A total of 45 patients with HF and 17 patients with EHR completed this prospective study. Baseline serum calcitriol levels were ≤ 60 pmol/l in 26% of the HF patients. After 7 weeks, they significantly decreased (p < 0.001). In patients with EHR, serum calcitriol was within the reference range in all but one patient and did not change during the 7-week recovery phase. Seven weeks after HF, a significant positive relationship was observed between the change in calcitriol and serum 25(OH)D concentration (r = 0.385, p = 0.009) and free 25(OH)D (r = 0.296, p = 0.048), and a decrease in calcitriol during recovery was associated with a decrease in serum PTH (p = 0.038). Seven weeks after HF, changes in both serum PTH and serum 25(OH)D concentrations contributed to the prediction of changes in serum calcitriol (R2 = 0.190, p = 0.012). CONCLUSIONS: Unlike patients with EHR, subjects with HF had low serum 25(OH)D and low free 25(OH)D concentrations at admission, while their serum 1,25D levels were relatively elevated. Decreases in circulating calcitriol levels in the 7 weeks following hip surgery were associated with a resolution of secondary hyperparathyroidism and low availability of free 25(OH)D.

• Klíčová slova
• Calcitriol, Fracture healing, Free 25 hydroxyvitamin D, Hip fracture, Total 25 hydroxyvitamin D,
• MeSH
• fraktury kyčle krev   MeSH
• hojení fraktur fyziologie   MeSH
• kalcitriol krev   MeSH
• lidé MeSH
• náhrada kyčelního kloubu MeSH
• osteogeneze MeSH
• parathormon krev   MeSH
• prospektivní studie MeSH
• referenční hodnoty MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• vitamin D analogy a deriváty   krev   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 25-hydroxyvitamin D MeSH Prohlížeč
• kalcitriol MeSH
• parathormon MeSH
• vitamin D MeSH