Drechsler Christiane, de Mutsert Renée, Grootendorst Diana C, Boeschoten Elisabeth W, Krediet Raymond T, le Cessie Saskia, Wanner Christoph, Dekker Friedo W
Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands.
Am J Kidney Dis. 2009 Jun;53(6):1014-23. doi: 10.1053/j.ajkd.2008.11.027. Epub 2009 Feb 13.
Obesity is a risk factor for loss of kidney function in the general population, but it is unknown whether it proceeds to affect residual kidney function when patients require dialysis. Our aim was to study the effects of body mass index (BMI) on decline in kidney function and risk to develop anuria after initiation of dialysis therapy.
Prospective cohort study.
SETTING & PARTICIPANTS: 1,271 incident dialysis patients from 38 centers in The Netherlands participating in the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD) between 1997 and 2006.
BMI assessed at 3 months after the initiation of dialysis therapy (baseline) and categorized into 4 groups: less than 20, 20 or greater to 25, 25 or greater to 30, and 30 or greater kg/m(2).
OUTCOMES & MEASUREMENTS: The decrease in measured glomerular filtration rate (mGFR) was determined by means of linear mixed models and adjusted for age, sex, primary kidney disease, dialysis modality, smoking, cardiovascular disease, and normalized protein nitrogen appearance and additionally for proteinuria, blood pressure, and baseline mGFR. Cox regression analysis was used to calculate hazard ratios for the development of anuria.
Patients had a mean age of 59 +/- 15 years, BMI of 24.8 +/- 4.1 kg/m(2), and mGFR of 4.7 +/- 3.3 mL/min. During 18 months of follow-up, the decrease in mGFR in patients with normal weight was 1.2 mL/min/y (95% confidence interval [CI], 0.7 to 1.6). Compared with those values, adjusted losses of mGFR were 0.4 mL/min/y (95% CI, 0.02 to 0.8) greater for overweight and 1.2 mL/min/y (95% CI, 0.5 to 1.8) greater for obese patients. In contrast, the decrease in underweight patients was 0.6 mL/min/y (-0.1 to 1.3) less. Anuria occurred in 297 patients; the risk was similar among BMI groups after adjustment for confounders and baseline diuresis.
Patients with missing BMI or mGFR values at baseline were excluded.
Obesity is a strong risk factor for the decline in kidney function after initiation of dialysis therapy. Whether obese dialysis patients might benefit from a healthy weight reduction needs to be studied further.
肥胖是普通人群肾功能丧失的一个风险因素，但在患者需要透析时肥胖是否会进而影响残余肾功能尚不清楚。我们的目的是研究体重指数（BMI）对透析治疗开始后肾功能下降及出现无尿风险的影响。
前瞻性队列研究。
1997年至2006年间，来自荷兰38个中心的1271例新发透析患者参与了荷兰透析充分性合作研究（NECOSAD）。
在透析治疗开始后3个月（基线）评估的BMI，并分为4组：小于20、20或大于等于20至25、25或大于等于25至30以及30或大于等于30kg/m²。
通过线性混合模型确定实测肾小球滤过率（mGFR）的下降情况，并对年龄、性别、原发性肾病、透析方式、吸烟、心血管疾病以及标准化蛋白氮出现率进行校正，另外还对蛋白尿、血压和基线mGFR进行校正。采用Cox回归分析计算无尿发生的风险比。
患者的平均年龄为59±15岁，BMI为24.8±4.1kg/m²，mGFR为4.7±3.3mL/min。在18个月的随访期间，体重正常患者的mGFR下降为1.2mL/min/年（95%置信区间[CI]，0.7至1.6）。与这些值相比，超重患者校正后的mGFR损失每年多0.4mL/min（95%CI，0.02至0.8），肥胖患者多1.2mL/min/年（95%CI，0.5至1.8）。相比之下，体重过轻患者的下降少0.6mL/min/年（-0.1至1.3）。297例患者出现无尿；在对混杂因素和基线尿量进行校正后，BMI组之间的风险相似。
排除了基线时BMI或mGFR值缺失的患者。
肥胖是透析治疗开始后肾功能下降的一个强烈风险因素。肥胖的透析患者是否可能从健康减重中获益需要进一步研究。
