Pre and post fracture vitamin d: variability linked to inflammation

Introduction: Vitamin D is a fat-soluble hormone with pleiotropic effects, whose deficiency in the elderly contributes to the development of osteoporosis and sarcopenia, increasing the risk of fractures, falls and consequent morbidity and mortality. Studies show a very low level of vitamin D in patients with hip fractures but it has never been shown whether there is an influence of inflammatory stress linked to surgery in reducing these levels or whether it is linked only to pre-fracture conditions. The aim of the study was to compare the circulating levels of 25-hydroxycholecalciferol, in the preand post-operative stages and to find a relation between the reduction of vitamin D levels and the inflammation markers in patients undergoing surgery for hip fracture. Methods: We recruit hip fracture patients aged over 65. Were excluded from the study: inoperable patients, those with secondary fractures to neoplastic diseases, subjects suffering from severe renal and hepatic impairment, those with known infections and bone metabolism diseases (primary hyperparathyroidism, Paget) and those undergoing systemic chronic corticosteroid therapy. Blood tests were performed for each patient at time zero (T0) and on the second post-operative day (T48), with the following parameters: blood count with formula, vitamin D (VIT D), PTH, PCR, albumin, D- Dimer, fibrinogen, ferritin, calcemia and creatinine. For each parameter have been evaluated: the variations, the significance of these and the possible correlations between them. Results: Our sample is made up of 50 patients: 41 females and 9 males, mean age:82.25 ± 8.11 years. The analysis of the blood tests carried out at time 0 and on the second post-operative day (T48) shows a statistically significant reduction (p <0.001) of postoperative VIT D values (11.37 ng / ml vs 9 , 4 ng / ml). Finally, the evaluation of the relationship between VIT D and inflammation markers, measured respectively at T0 and T48, shows only an inverse correlation between VIT D levels and PCR (p = 0.044, r = - 0,289) which significantly increase (p <0.001) in the post-operative period (5.45 mg / dl vs 14 mg / dl). Conclusion: In literature there is evidence of a link between VIT D levels and systemic inflammatory level, typical of subjects suffering from fragility fractures and surgically treated, probably due to the utilization of vitamin D storage during the antiinflammatory reaction. Our pilot study shows that the VIT D values, already deficient in most of our elderly patients, are further reduced after surgery. The relation with PCR could be explained by the evidence of a genetic link between vitamin D and PCR; in fact some polymorphisms (SNP) in the PCR gene predispose to a phenotype with high PCR values and reduced vitamin values. By the importance of Vitamin D in the postfracture and the high perioperative inflammatory level of elderly patients with hip fractures, a supplementation of VIT D should be prescribed.