Diabetes mellitus and osteoporosis after organ transplantation: Frequency, clinical features, and treatment

BACKGROUND: Organ transplantation is an effective treatment option, often the last remaining one, for terminal organ failure. 22-32% of transplant recipients, however, develop metabolic-endocrine complications that markedly impair transplant function and overall survival. We provide an evidence-based narrative review of the clinical features, diagnostic evaluation, and treatment of post-transplantation diabetes mellitus (PTDM) and osteoporosis. METHODS: This review is based on pertinent publications that were retrieved by a selective search in PubMed, MEDLINE, and the Cochrane Library (01/1995-09/2025), including systematic reviews, clinical studies, randomized controlled trials, register data analyses, observational studies, and guidelines. RESULTS: Post-transplantation diabetes affects 9-40% of organ recipients in the first year after transplantation, corresponding to a two- to threefold risk elevation compared to the general population. Its incidence and course are organ-specific and characterized by further risk factors, including a 3.3-fold elevation of the risk of cardiovascular events. Studies have shown that, alongside insulin and metformin, newer antidiabetic agents such as GLP-1 receptor agonists and SGLT2 inhibitors also improve glycemic control, reduce cardiovascular events, and, as far as can be determined, do not endanger the transplant. Transplantation-associated osteoporosis affects 23-67% of transplant recipients, causing the most marked bone loss in the first 6-18 months after transplantation. Approximately 20% of the affected patients sustain fractures. Bisphosphonate, denosumab, and teriparatide have been found to be treatment options. Treatment should be initiated as early as possible. CONCLUSION: Thorough screening and timely, specialist-coordinated interdisciplinary care in specialized transplantation centers are decisive for the recognition and risk-adapted, evidence-based treatment of PTDM and transplantation-associated osteoporosis.