Fri0500 incidence of Clinical Fractures in Adults With Kidney Transplant

Abstract

BackgroundChronic kidney disease is associated with an increased risk of fractures. However, the existing evidence investigating the incidence of fractures after kidney transplant is scarce.ObjectivesTo evaluate the incidence of clinical fractures in patients with kidney transplant and analyze the possible factors that may influence its occurrence.MethodsA retrospective observational study of patients who underwent kidney transplant between 2005 and 2015 in a tertiary hospital was conducted. A minimum follow.up period of 6months after transplant was required. Sociodemographic and anthropometric data, clinical risk factors for bone fractures, drugs use (steroids, immunosuppressive drugs, vitamin D analogues, calcium and vitamin D supplements and calcimimetics), as well as biochemical and densitometric data to assess bone metabolism were retrieved from medical records. The occurrence of new clinical fractures after the transplant and throughout the follow-up period was recorded. The statistical analysis included univariable analysis using chi-square and Fisher’s exact tests for the qualitative variables and T-Student and Mann-Whitney U for the quantitative variables. Subsequently, logistic regression multivariable analysis was carried out to investigate which factors were associated with fractures occurrence.ResultsA total of 163 patients were included, 63 (38%) females, with a mean age of 51 ± 14.6 years. The etiology of kidney disease was polycystic kidney disease (24.2%), glomerulonephritis (23.6%), diabetes mellitus (5.5%), vasculopathy (5.5%), connective tissue disorders (2.4%) and miscellany (38.7%). The daily average dose of steroids one year after transplant was 5.8 ± 4.4 mg. Bone densitometry was performed before transplant in 27 patients (19.6%), ten of whom (37%) presented osteopenia and 7 (26%) osteoporosis. The ten-year probability of bone fracture risk (FRAX) before transplant was 2.6 ± 2.6. Mean follow-up after transplant was 8.7 ± 3.5 years. During this period, 23 (13.9%) patients suffered a clinical fracture, with an average time of appearance after transplant of 5.5 ± 3.3 years. These were located in hip (6 - 26.1%), vertebrae (2- 8.7%), extremities (9 – 39.1%) and hands and feet (6 – 26%). One year after transplant, 65.6% had vitamin D deficiency (<30 ng/dl serum calcidiol leves) and 12.2% had levels compatible with osteomalacic range (<10ng/dl). The data of the descriptive study stratified by the fracture occurrence are shown in Table 1. Compared with the subgroup patients without (Fx -), patients with (Fx +) post-transplant fractures showed to be more frequely female (60.9% vs 34.5%, p=0.01), older (50.1 ± 14.6 vs 56.3 ± 14.1 p=0.03), had more pre-transplant major clinical FRAX ((2.4 ± 1.9 vs 4 ± 4.7, p=0.03), and higher levels of PTH (98.2 ± 75.7 vs 140.1 ± 86.9 p=0.02) and serum alkaline phosphatase [ALP] (90.2 ± 37 vs 117.8 ± 60.4, p=0.02) after one year of transplant. Also, a trend to present a higher prevalence of pre-transplant clinical fractures was observed in the second group (5.6% vs 1...