Supplementary Material for: Factors and Outcome of Renal Osteodystrophy-Associated Initial Fragility Fracture in End-Stage Renal Disease Patients

Background: Renal osteodystrophy has caused increased risk of fragility fracture in end-stage renal disease (ESRD) patients. However, risk factors and outcome of ESRD patients with fragility fracture remain uncharacterized. We aimed to assess these parameters in ESRD patients. Summary: This retrospective case-control study analyzed 354 ESRD patients (initial fragility fracture [FF] group, n = 59; control group, n = 295). Pre-dialysis blood hemoglobin, serum albumin, lipid, calcium, phosphorus, alkaline phosphatase (ALP), and intact parathyroid hormone (iPTH) were collected. All procedures performed involving human participants were in accordance with the ethical standards of the institutional committee of The First Affiliated Hospital of Chongqing Medical University (IRB approval number 216-82), and informed consent was obtained from all participants. There were higher prevalence rates of primary hypertension and diabetes, higher serum ALP, corrected calcium, and lower serum total cholesterol, low-density lipoprotein, lipoprotein-α, and iPTH in the FF group. Fractures were more likely to occur in the higher level of corrected calcium as well as in the lower iPTH group. High corrected calcium (p = 0.010, OR = 11.308, 95% CI: 1.770–72.242) and serum ALP (p = 0.000, OR = 1.007, 95% CI: 1.004–1.011) were independent risk factors of fragility fracture. The incidence of all-cause mortality and cardiovascular (CV) events in ESRD patients with fragility fracture was higher than in those without fracture. Key Messages: Patients with hypertension, diabetes, excessive suppression of PTH, and poor nutritional status are more prone to fractures. Serum corrected calcium and ALP were independent risk factors of fragility fracture. Patients with initial fragility fracture had more CV events and higher mortality.

研究背景：肾性骨病（Renal osteodystrophy）会升高终末期肾病（end-stage renal disease, ESRD）患者发生脆性骨折的风险。然而，目前针对合并脆性骨折的终末期肾病患者的危险因素与预后仍尚不明确。本研究旨在对该类患者的相关参数进行评估。
研究概况：本回顾性病例对照研究（retrospective case-control study）共纳入354名终末期肾病患者，分为初诊脆性骨折（initial fragility fracture, FF）组（n=59）与对照组（n=295）。收集了所有患者透析前的血红蛋白、血清白蛋白、血脂、血钙、血磷、碱性磷酸酶（alkaline phosphatase, ALP）以及全段甲状旁腺激素（intact parathyroid hormone, iPTH）等指标。本研究所有涉及人体受试者的操作均符合重庆医科大学附属第一医院伦理委员会的伦理标准（伦理审查批准号：216-82），且所有受试者均签署了知情同意书。与对照组相比，初诊脆性骨折组患者的原发性高血压与糖尿病患病率更高，血清ALP、校正血钙水平更高，而血清总胆固醇、低密度脂蛋白、脂蛋白-α以及iPTH水平更低。脆性骨折更易发生于校正血钙水平较高以及iPTH水平较低的患者群体中。高校正血钙水平（p=0.010，OR=11.308，95%CI：1.770–72.242）与血清ALP水平（p=0.000，OR=1.007，95%CI：1.004–1.011）是脆性骨折的独立危险因素。合并脆性骨折的终末期肾病患者的全因死亡率与心血管（cardiovascular, CV）事件发生率均显著高于无脆性骨折的患者。
核心结论：合并高血压、糖尿病、甲状旁腺激素过度抑制以及营养状况不佳的患者更易发生脆性骨折；血清校正血钙与ALP水平是脆性骨折的独立危险因素；初诊脆性骨折患者的心血管事件发生率更高，预后死亡率也更高。