不同蛋白质摄入对慢性肾脏病3期患者肾功能的影响

目的 分析饮食中不同平均每日蛋白质摄入水平对慢性肾脏病(chronic kidney disease,CKD)3期患者肾功能的影响。方法 选择2013年1月至2015年5月在首都医科大学附属北京友谊医院CKD门诊规律随访时间超过24个月的CKD3期患者进行回顾性分析,收集患者的一般资料,包括原发病、实验室检查、饮食回顾等,计算出患者饮食中平均每日蛋白质摄入量(dietary protein intake,DPI)。将按平均DPI分为3组:DPI ≤ 0.6 g·kg^-1·d^-1为极低蛋白饮食(very low protein diet,VLPD)组;DPI在0.6~0.8 g·kg^-1·d^-1为低蛋白饮食(low protein diet,LPD)组;DPI > 0.8 g·kg^-1·d^-1为高蛋白饮食(normal protein diet,NPD)组。应用简化肾脏病饮食改良(modification of diet in renal disease,MDRD)公式估算肾小球滤过率(estimated glomerular filtration rate,eGFR),并比较不同DPI分组下肾功能随时间的下降情况。结果 本研究共入选221例患者,其中VLPD组61例、LPD组118例、NPD组42例患者;经过重复测量的方差分析比较发现,基线水平下3组患者eGFR差异无统计学意义(P > 0.05),随访过程中,VLPD组和NPD组CKD患者eGFR较基线水平有逐步下降趋势,二者下降速率相似,但随访至第24个月时差异无统计学意义(P=0.050,P=0.054),而随访过程中LPD组eGFR与基线相比则无明显降低。随访至24个月,VLPD组与LPD组相比eGFR有所降低,差异有统计学意义(P=0.024),而NPD组eGFR与LPD组相比虽有所下降,但差异无统计学意义(P=0.068)。结论 对CKD3期患者而言,低蛋白摄入对延缓肾功能进展可能存在一定的保护作用,但极低蛋白摄入则可能会增加肾功能恶化的风险。

Retrospective analysis of influences of different protein intake on renal function in patients with stage 3 chronic kidney disease

Objective To explore retrospectively the influence of different protein intake on renal prognosis in patients with stage 3 chronic kidney disease(CKD). Methods Follow up data was successfully obtained in the 221 patients with stage 3 CKD who followed more than 24 months from January 2013 to May 2015, the clinical data and laboratory tests were collected, including primary disease, body mass index, diet reviews, daily protein intake(DPI) and laboratory tests. A simplified modification of diet in renal disease(MDRD) formula was adopted to calculate the level of estimated glomemlar filtration rate(eGFR). The patients were divided into 3 groups according to the level of DPI: very low protein diet(VLPD) as DPI ≤ 0.6 g·kg^-1·d^-1(n=61), low protein diet(LPD) as DPI from 0.6 to 0.8 g·kg^-1·d^-1(n=118) and normal protein diet(NPD) as DPI > 0.8 g·kg^-1·d^-1(n=42). Results There were no significant difference between 3 groups in eGFR level at the baseline(P > 0.05). However, the eGFR of VLPD and NPD group tend to decrease progressively in a similar rate with the prolonging of time, both were merely missed the statistically significance compared with each baseline level at the end of the observation(P=0.050, P=0.054), and no decrease was observed in NPD group. Compared with LPD group, the eGFR level of VLPD group significantly decreased on month 24(P=0.024). Conclusion The low-protein diet(DPI between 0.6-0.8 g·kg^-1·d^-1) may contribute to delaying the deterioration of renal function, but the very low protein diet(DPI ≤ 0.6 g·kg^-1·d^-1) may increase the risk of the progress of CKD.