Denic Aleksandar, Glassock Richard J, Rule Andrew D
Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN; Department of Medicine, Geffen School of Medicine at UCLA, Los Angeles, CA; and Division of Nephrology and Hypertension, Division of Epidemiology, Mayo Clinic, Rochester, MN.
Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN; Department of Medicine, Geffen School of Medicine at UCLA, Los Angeles, CA; and Division of Nephrology and Hypertension, Division of Epidemiology, Mayo Clinic, Rochester, MN.
Adv Chronic Kidney Dis. 2016 Jan;23(1):19-28. doi: 10.1053/j.ackd.2015.08.004.
Senescence or normal physiologic aging portrays the expected age-related changes in the kidney as compared to a disease that occurs in some but not all individuals. The microanatomical structural changes of the kidney with older age include a decreased number of functional glomeruli from an increased prevalence of nephrosclerosis (arteriosclerosis, glomerulosclerosis, and tubular atrophy with interstitial fibrosis), and to some extent, compensatory hypertrophy of remaining nephrons. Among the macroanatomical structural changes, older age associates with smaller cortical volume, larger medullary volume until middle age, and larger and more numerous kidney cysts. Among carefully screened healthy kidney donors, glomerular filtration rate (GFR) declines at a rate of 6.3 mL/min/1.73 m(2) per decade. There is reason to be concerned that the elderly are being misdiagnosed with CKD. Besides this expected kidney function decline, the lowest risk of mortality is at a GFR of ≥75 mL/min/1.73 m(2) for age <55 years but at a lower GFR of 45 to 104 mL/min/1.73 m(2) for age ≥65 years. Changes with normal aging are still of clinical significance. The elderly have less kidney functional reserve when they do actually develop CKD, and they are at higher risk for acute kidney injury.
衰老或正常生理老化描述了肾脏中预期的与年龄相关的变化，这与某些个体而非所有个体发生的疾病形成对比。随着年龄增长，肾脏的微观解剖结构变化包括由于肾硬化（动脉硬化、肾小球硬化以及伴有间质纤维化的肾小管萎缩）患病率增加导致功能性肾小球数量减少，以及在一定程度上剩余肾单位的代偿性肥大。在宏观解剖结构变化方面，年龄增长与皮质体积减小、中年之前髓质体积增大以及肾囊肿更大且数量更多相关。在经过仔细筛选的健康肾脏供体中，肾小球滤过率（GFR）每十年以6.3 mL/min/1.73 m²的速率下降。有理由担心老年人被误诊为慢性肾脏病。除了这种预期的肾功能下降外，年龄<55岁时，死亡率最低的GFR为≥75 mL/min/1.73 m²，但年龄≥65岁时，GFR为45至104 mL/min/1.73 m²时死亡率最低。正常衰老过程中的变化仍具有临床意义。老年人在实际发生慢性肾脏病时肾功能储备较少，并且发生急性肾损伤的风险更高。
