血液透析患者营养指标与骨密度及骨折风险的相关性研究

目的 分析营养指标对维持性血液透析患者骨密度及骨折风险的影响。方法 横断面+前瞻观察性队列研究。设非慢性肾脏病对照，测定跟骨超声骨密度，透析患者同时评估臀围等营养指标，随访骨折发生情况。结果 入组透析患者131例、对照77例；透析患者骨密度T值低于对照（中位值分别为?2.9和?2.0, P<0.001），多种因素校正后仍如此（F=11.042，P=0.001）；多元线性回归分析显示骨密度与透析、年龄、性别相关（P值均<0.05），与腰围、体质指数等无关，对血液透析患者单独分析则骨密度只与年龄、性别相关（P 分别为0.02，0.005）。平均随访81.0月，透析患者发生骨折10例(7.6 %)；Logistic回归分析显示在调整了骨密度、糖尿病、甲状旁腺激素等指标后透析龄长、臀围大、体质指数低、贫血重的患者骨折风险高OR((95% CI)分别为1.029(1.007~1.051)，1.485(1.016~2.171)，0.414(0.193~0.891)，0.827(0.691~0.989)；均P <0.05]。结论 血液透析患者骨密度低于对照，并且独立于营养指标等多种因素；臀围、体质指数等指标影响新发骨折风险，提示透析患者减小臀围、提高体质指数可能减少骨折风险。

Association between nutritional indices and bone mineral density and fracture risk in patients undergoing maintenance hemodialysis

Objective To analyze the association between nutritional indices between bone mineral density (BMD) and risk of fracture in patients undergoing maintenance hemodialysis. Methods This was a cross-sectional and prospective observational cohort study. A non-chronic kidney disease (CKD) control group was set. Calcaneus ultrasonic BMD T score was measured. Hip circumference and other nutritional indices were measured for patients on hemodialysis who were followed up for incident fracture events. Results One hundred and thirty-one patients on stable hemodialysis and 77 controls were enrolled. BMD T scores of hemodialysis patients were significantly lower than those in controls (?2.9 vs ?2.0, P<0.001). It was consistent after adjudication for multiple factor adjudication (F=11.042, P=0.001). Multivariate linear regression analysis demonstrated that BMD was associated with dialysis, age, and sex significantly, but was not associated with hip circumference and body mass index(BMI). Meanwhile, it demonstrated that age and sex were associated with BMD (P values were 0.02 and 0.005, respectively) for patients on hemodialysis alone. Ten incident fractures occurred (7.6%) over the median follow-up of 81.0 months. Multivariate binary logistic regression analysis showed that longer years on hemodialysis therapy, larger hip circumference, lower BMI, and more severe anemia contributed to higher risk of incident fractures. OR (95% CI) values were 1.029 (1.007, 1.051), 1.485(1.016, 2.171), 0.414(0.193, 0.891), and 0.827(0.691, 0.989), respectively (all P <0.05) after controlling for BMD, diabetes, and parathyroid hormone etc. Conclusion This study shows that calcaneus BMD T scores in hemodialysis patients are lower than those in non-CKD controls, which was independent on nutritional indices etc. Nutritional indices including larger hip circumference and lower BMI etc contributed to higher risk of incident fracture, which suggested that reducing hip circumference and improving BMI may decrease the risk of incident fracture in patients on hemodialysis.