Department of Epidemiology, School of Public Health, University of California, Berkeley, CA, USA.
Nephrol Dial Transplant. 2010 Feb;25(2):463-9. doi: 10.1093/ndt/gfp474. Epub 2009 Sep 11.
Kidney function declines with age, but a substantial portion of this decline has been attributed to the higher prevalence of risk factors for kidney disease at older ages. The effect of age on kidney function has not been well described in a healthy population across a wide age spectrum.
The authors pooled individual-level cross-sectional data from 18 253 persons aged 28-100 years in four studies: the Cardiovascular Health Study; the Health, Aging and Body Composition Study; the Multi-Ethnic Study of Atherosclerosis and the Prevention of Renal and Vascular End-Stage Disease cohort. Kidney function was measured by cystatin C. Clinical risk factors for kidney disease included diabetes, hypertension, obesity, smoking, coronary heart disease, cerebrovascular disease, peripheral arterial disease and heart failure.
Across the age range, there was a strong, non-linear association of age with cystatin C concentration. This association was substantial, even among participants free of clinical risk factors for kidney disease; mean cystatin C levels were 46% higher in participants 80 and older compared with those <40 years (1.06 versus 0.72 mg/L, P < 0.001). Participants with one or more risk factors had higher cystatin C concentrations for a given age, and the age association was slightly stronger (P < 0.001 for age and risk factor interaction).
There is a strong, non-linear association of age with kidney function, even in healthy individuals. An important area for research will be to investigate the mechanisms that lead to deterioration of kidney function in apparently healthy persons.
肾脏功能随年龄增长而下降，但其中相当一部分下降归因于老年人群中肾脏疾病风险因素的更高患病率。在广泛的年龄范围内，健康人群中年龄对肾脏功能的影响尚未得到很好的描述。
作者汇总了四项研究（心血管健康研究、健康、衰老和身体成分研究、动脉粥样硬化多民族研究和预防肾脏和血管终末期疾病队列研究）中 18253 名年龄在 28-100 岁的个体的个体水平横断面数据。肾脏功能通过半胱氨酸蛋白酶抑制剂 C 来测量。肾脏疾病的临床风险因素包括糖尿病、高血压、肥胖、吸烟、冠心病、脑血管病、外周动脉疾病和心力衰竭。
在整个年龄范围内，年龄与半胱氨酸蛋白酶抑制剂 C 浓度之间存在强烈的、非线性的关联。即使在没有肾脏疾病临床风险因素的参与者中，这种关联也很大；80 岁及以上的参与者的平均半胱氨酸蛋白酶抑制剂 C 水平比<40 岁的参与者高 46%（1.06 与 0.72mg/L，P<0.001）。有一个或多个风险因素的参与者在给定年龄时具有更高的半胱氨酸蛋白酶抑制剂 C 浓度，且年龄相关性略强（年龄与风险因素交互作用的 P<0.001）。
即使在健康个体中，年龄与肾脏功能之间也存在强烈的、非线性的关联。一个重要的研究领域将是调查导致健康人群中肾脏功能恶化的机制。
