Analysis of Risk Factors Affecting Incidence of Osteoporosis and Fragility Fractures in Liver Transplant Recipients.

BACKGROUND Fragility fractures caused by osteoporosis are common complications seen in recipients of organ transplantation who survive long term. Although many risk factors have been identified for osteoporosis after organ transplantation, none of them have been recognized as the main cause of development of the condition. Several studies have examined vitamin D receptor (VDR) gene single-nucleotide polymorphisms (SNPs) for their influence on bone mineral density (BMD) and fracture risk, but with variable results. We aimed to elucidate the risk factors that affect incidence of osteoporosis and fragility fractures in liver transplant recipients. MATERIAL AND METHODS In this study, we monitored incidence of fragility fracture and osteoporosis in 45 patients who had been evaluated with dual-energy X-ray absorptiometry (DXA) after liver transplantation. We also analyzed the association between VDR SNPs such as BsmI, ApaI, FokI, and TaqI with osteoporosis and fracture incidence in 27 patients in our cohort in whom SNPs were evaluated and DXA performed after liver transplantation. RESULTS Osteoporosis was diagnosed in 17 of 45 patients in whom BMD was measured after liver transplantation. Of the patients with osteoporosis, 15 (88.2%) subsequently had fragility fractures. The incidence of postoperative osteoporosis was significantly higher in the recipients who had alcoholic liver cirrhosis as their primary disease. Interestingly, there were significantly more patients with a homozygous BsmI GG genotype in the group diagnosed with osteoporosis. CONCLUSIONS Our study suggests that patients who undergo liver transplantation and have alcoholic liver cirrhosis or the BsmI GG genotype may be at increased risk for osteoporosis. Further research is necessary to confirm these findings.