Commonwealth Scientific and Industrial Research Organisation, Gate 13, Kintore Avenue, Adelaide, Australia.
Int J Obes (Lond). 2012 Nov;36(11):1421-7. doi: 10.1038/ijo.2011.242. Epub 2011 Dec 20.
To combat the increasing incidence of obesity, much research has been devoted to devising successful strategies for weight loss, including manipulation of diet and gastric surgery. Obesity itself can be associated with renal dysfunction, and the degree of reversibility of this with weight loss has being studied. However, there are significant limitations and flaws in the methods we have available to measure glomerular filtration rate (GFR) in overweight and obese subjects. Obesity is associated with changes in body composition including lean and fat mass. This has implications for assumptions that underpin creatinine-based measures such as creatinine clearance, estimated GFR and other equations devised for obesity including the Salazar-Corcoran equation. These changes in body composition also affect measures of glomerular filtration such as cystatin C and nuclear medicine isotope scans. This article will review the accuracy of these current measures of renal function in the obese and consider the evidence for adjusting for body surface area or adjusting for lean body mass. Finally, the effect of weight loss itself on serial measurements of renal function in a given individual, independent of a true change in renal function, will be reviewed. Ultimately using the Cockcroft-Gault equation with an adjustment for lean body mass seems to be the best measure for renal function in obesity. No method for measuring renal function in situations of weight loss has been shown to be unequivocally superior.
为了应对肥胖发病率的不断上升，许多研究致力于制定成功的减肥策略，包括饮食控制和胃手术。肥胖本身可能与肾功能障碍有关，人们已经研究了体重减轻对这种情况的可逆程度。然而，我们现有的测量超重和肥胖人群肾小球滤过率（GFR）的方法存在显著的局限性和缺陷。肥胖与身体成分的变化有关，包括瘦体重和脂肪量。这对基于肌酐的测量方法（如肌酐清除率、估计肾小球滤过率和包括 Salazar-Corcoran 方程在内的肥胖相关方程）所依据的假设产生了影响。这些身体成分的变化也会影响到肾小球滤过的测量，如胱抑素 C 和核医学同位素扫描。本文将回顾这些目前用于肥胖人群的肾功能测量方法的准确性，并考虑为身体表面积或瘦体重调整这些方法的证据。最后，将回顾体重减轻本身对特定个体肾功能的连续测量的影响，而不考虑肾功能的真实变化。最终，使用调整瘦体重的 Cockcroft-Gault 方程似乎是肥胖患者肾功能的最佳测量方法。目前还没有一种方法可以在减肥的情况下被明确证明是优越的。
