NHMRC CKD.CRE and CKD.QLD, Health Science Building, Level 8, University of Queensland, RBWH, Brisbane, Herston, QLD 4029, Australia.
Centre for Chronic Disease, Health Science Building, Level 8, University of Queensland, RBWH, Brisbane, Herston, QLD 4029, Australia.
BMC Nephrol. 2019 Aug 22;20(1):329. doi: 10.1186/s12882-019-1513-9.
A survival advantage associated with obesity has often been described in dialysis patients. The association of higher body mass index (BMI) with mortality and renal replacement therapy (RRT) in preterminal chronic kidney disease (CKD) patients has not been established.
Subjects were patients with pre-terminal CKD who were recruited to the CKD.QLD registry. BMI at time of consent was grouped as normal (BMI 18.5-24.9 kg/m), overweight (BMI 25-29.9 kg/m), mild obesity (BMI 30-34.9 kg/m) and moderate obesity+ (BMI ≥ 35 kg/m) as defined by WHO criteria. The associations of BMI categories with mortality and starting RRT were analysed.
The cohort consisted of 3344 CKD patients, of whom 1777 were males (53.1%). The percentages who had normal BMI, or were overweight, mildly obese and moderately obese+ were 18.9, 29.9, 25.1 and 26.1%, respectively. Using people with normal BMI as the reference group, and after adjusting for age, socio-economic status, CKD stage, primary renal diagnoses, comorbidities including cancer, diabetes, peripheral vascular disease (PVD), chronic lung disease, coronary artery disease (CAD), and all other cardiovascular disease (CVD), the hazard ratios (HRs, 95% CI) of males for death without RRT were 0.65 (0.45-0.92, p = 0.016), 0.60 (0.40-0.90, p = 0.013), and 0.77 (0.50-1.19, p = 0.239) for the overweight, mildly obese and moderately obese+. With the same adjustments the hazard ratios for death without RRT in females were 0.96 (0.62-1.50, p = 0.864), 0.94 (0.59-1.49, p = 0.792) and 0.96 (0.60-1.53, p = 0.865) respectively. In males, with normal BMI as the reference group, the adjusted HRs of starting RRT were 1.15 (0.71-1.86, p = 0.579), 0.99 (0.59-1.66, p = 0.970), and 0.95 (0.56-1.61, p = 0.858) for the overweight, mildly obese and moderately obese+ groups, respectively, and in females they were 0.88 (0.44-1.76, p = 0.727), 0.94 (0.47-1.88, p = 0.862) and 0.65 (0.33-1.29, p = 0.219) respectively.
More than 80% of these CKD patients were overweight or obese. Higher BMI seemed to be a significant "protective" factor against death without RRT in males but there was not a significant relationship in females. Higher BMI was not a risk factor for predicting RRT in either male or female patients with CKD.
肥胖与透析患者的生存优势有关，这一现象经常被描述。但在终末期慢性肾脏病（CKD）患者中，更高的体重指数（BMI）与死亡率和肾脏替代治疗（RRT）的关系尚未确定。
本研究纳入了参与 CKD.QLD 注册研究的终末期 CKD 患者。在同意时的 BMI 分为正常（BMI 18.5-24.9 kg/m）、超重（BMI 25-29.9 kg/m）、轻度肥胖（BMI 30-34.9 kg/m）和中度肥胖+（BMI ≥ 35 kg/m），这些分类是根据世界卫生组织的标准来定义的。分析了 BMI 类别与死亡率和开始 RRT 的关系。
该队列包括 3344 名 CKD 患者，其中 1777 名男性（53.1%）。正常 BMI、超重、轻度肥胖和中度肥胖+的患者比例分别为 18.9%、29.9%、25.1%和 26.1%。以正常 BMI 患者为参考组，在调整年龄、社会经济地位、CKD 分期、原发性肾脏诊断、包括癌症、糖尿病、外周血管疾病（PVD）、慢性肺部疾病、冠心病（CAD）和所有其他心血管疾病（CVD）在内的合并症后，男性无 RRT 死亡的风险比（HR，95%CI）分别为 0.65（0.45-0.92，p=0.016）、0.60（0.40-0.90，p=0.013）和 0.77（0.50-1.19，p=0.239）。对于女性，在进行相同调整后，无 RRT 死亡的风险比分别为 0.96（0.62-1.50，p=0.864）、0.94（0.59-1.49，p=0.792）和 0.96（0.60-1.53，p=0.865）。在男性中，以正常 BMI 为参考组，开始 RRT 的调整 HR 分别为 1.15（0.71-1.86，p=0.579）、0.99（0.59-1.66，p=0.970）和 0.95（0.56-1.61，p=0.858）。对于女性，这些值分别为 0.88（0.44-1.76，p=0.727）、0.94（0.47-1.88，p=0.862）和 0.65（0.33-1.29，p=0.219）。
这些 CKD 患者中超过 80%的患者超重或肥胖。较高的 BMI 似乎是男性无 RRT 死亡的一个显著“保护”因素，但在女性中没有显著的关系。较高的 BMI 并不是预测男性或女性 CKD 患者 RRT 的风险因素。
