Parathyroid hormone response to severe vitamin D deficiency is sex associated: An observational study of 571 hip fracture inpatients

• Published in: The Journal of nutrition, health & aging health & aging, 2013-02, Vol.17 (2), p.180-184
• Main Authors: Di Monaco, Marco, Castiglioni, C, Vallero, F, Di Monaco, R, Tappero, R
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Aging; albumins; Biological and medical sciences; blood serum; calcium; Creatinine; Creatinine - blood; Cross-Sectional Studies; Endocrinopathies; Enzymes; Feeding. Feeding behavior; Female; Fractures; Fundamental and applied biological sciences. Psychology; Geriatric Assessment; Geriatrics/Gerontology; glomerular filtration rate; hip fractures; Hip Fractures - blood; Hip Fractures - etiology; Hip joint; Humans; hypercalcemia; hyperparathyroidism; Hyperparathyroidism, Secondary - epidemiology; Hyperparathyroidism, Secondary - etiology; hypoparathyroidism; Hypoparathyroidism - epidemiology; Hypoparathyroidism - etiology; magnesium; Male; Medical sciences; Medicine; Medicine & Public Health; men; Mortality; Neurosciences; Non tumoral diseases. Target tissue resistance. Benign neoplasms; Nutrition; Observation; Observational studies; Odds Ratio; Orthopedics; Osteoporosis; parathyroid hormone; Parathyroid Hormone - blood; Parathyroids. Parafollicular cells. Cholecalciferol. Phosphocalcic homeostasis (diseases); patients; Prevalence; Primary Care Medicine; Qualitative Research; Quality of Life Research; Rehabilitation; Severity of Illness Index; Sex Factors; Trace Elements - blood; Trauma; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vitamin D; Vitamin D - analogs & derivatives; Vitamin D - blood; vitamin D deficiency; Vitamin D Deficiency - blood; Vitamin D Deficiency - complications; Vitamin deficiency; women
• ISSN: 1279-7707; 1760-4788
• DOI: 10.1007/s12603-012-0088-y

OBJECTIVES: To investigate the association between sex and parathyroid hormone response to severe vitamin D deficiency after hip fracture. DESIGN: Cross-sectional study. SETTING: Rehabilitation hospital in Italy. PARTICIPANTS: 571 consecutive inpatients with hip fracture and severe vitamin D deficiency (serum 25-hydroxyvitamin D < 12ng/ml), without hypercalcemia or estimated glomerular filtration rate (GFR) < 15ml/min. MEASUREMENTS: In each patient we assessed PTH (by two-site chemiluminescent enzyme-labelled immunometric assay), 25-hydroxyvitamin D (by immunoenzymatic assay), albumin-adjusted total calcium, phosphate, magnesium, and creatinine 21.3 ± 6.1 (mean ± SD) days after fracture occurrence. Functional level was assessed using the Barthel index. PTH response to vitamin D deficiency was classified as either secondary hyperparathyroidism (serum PTH >75pg/ml) or functional hypoparathyroidism, i.e., inappropriate normal levels of PTH (≤75pg/ml). RESULTS: Among the 571 patients, 336 (59%) had functional hypoparathyroidism, whereas 235 (41%) had secondary hyperparathyroidism. PTH status was significantly different between sexes (p=0.003): we found functional hypoparathyroidism in 61% of women and 43% of men (secondary hyperparathyroidism in 39% of women and 57% of men). The significance of the between-sex difference was maintained after adjustment for age, estimated GFR, phosphate, albumin-adjusted total calcium, albumin, Barthel index scores, 25-hydroxyvitamin D, and hip fracture type (either cervical or trochanteric). The adjusted odds ratio was 1.85 (95%CI from 1.09 to 3.13; p=0.023). CONCLUSIONS: Data shows that PTH response to vitamin D deficiency was sex-associated following a fracture of the hip. The higher prevalence of secondary hyperparathyroidism may play a role in the known prognostic disadvantage found in hip-fracture men.