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Hori Mayuko; Takahashi Hiroshi; Kondo Chika; Matsuoka Yutaka; Tsujita Makoto; Nishihira Morikuni; Uchida Kazuharu; Takeda; Morozumi Kunio; Maruyama Shoichi: Coexistence of Low Muscle Mass and Osteoporosis as a Predictor of Fragility Fractures in Long-Term Kidney Transplant Recipients. American Journal of Nephrology DOI 10.1159/000534019
Long-term survivors of kidney transplantation suffer from numerous complications. Often, they die due to side effects of immunosuppressive medications. Low bone mineral density (BMD; often equated with “osteoporosis”) and low muscle mass (LMM; “sarcopenia”) are among these complications, frequently attributed to steroid use.
Hori and co-workers conducted a retrospective observational study in 342 stable kidney transplant (KT) recipients after a median follow-up of about 5 years using DEXA scanning for BMD and bioelectric impedance for LMM.
As expected, low BMD was associated with excess fracture risk. No bone biopsies were performed, so the cause of low BMD was not firmly established. LMM was found in about one-third of subjects and the combination of low BMD and LMM increased the risk of fractures substantially, even after adjustment for many co-morbid factors, perhaps because LMM is a feature of frailty and excess falls. Steroid use, but not dosage, was one of several co-morbidity adjustments.
“Osteo-sarcopenia” in KT appears to be a real phenomenon, with clinically important consequences. An increased risk of fracture associated with “osteo-sarcopenia” is present in this study, but the underlying causes, including cumulative steroid dosage exposure and frailty, remain underexplored and this study cannot inform practitioners how to best attenuate fracture risk in such patients.
