Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea.
Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
Kidney Blood Press Res. 2019;44(5):1101-1114. doi: 10.1159/000502354. Epub 2019 Sep 18.
Diet modification, especially a decrease in salt intake, might be an important non-pharmacological strategy to improve chronic kidney disease (CKD) prognosis.
We conducted a prospective cohort study to investigate whether an intensive low-salt diet education program effectively attenuated the rate of renal function decline in hypertensive patients with CKD.
This cohort study recruited 171 participants from a previous open-labelled, case-controlled, randomized clinical trial that originally consisted of 245 hypertensive CKD patients who were assigned to two groups, intensive low-salt diet or conventional education. We evaluated the renal outcomes, which included the rate of change in estimated glomerular filtration rate (eGFR) per year, the increase in serum creatinine ≥50%, the decrease in eGFR ≥30%, and the percent change in albuminuria throughout the entire study period.
The baseline characteristics of the cohort participants between the two groups were similar at the time of trial phase randomization. During the whole study period, the rate of renal function decline was significantly faster in the conventional group (0.11 ± 4.63 vs. -1.53 ± 3.04 mL/min/1.73 m2/year, p = 0.01). The percent of incremental change in serum creatinine ≥50% was 1.1% in the intensive group and 8.2% in the conventional group (p = 0.025), and the percent of decremental change in eGFR ≥30% was 3.3% in the intensive group and 11.1% in the conventional group (p= 0.048). With logistic regression analysis adjusted for related factors, we found that the conventional group showed a higher risk for deterioration in serum creatinine and eGFR during the entire study period. Especially, we found that the intensive education program preserved eGFR in participants with one, several, or all of the following characteristics at the time of randomization: older age, female, obese, had higher protein intake, higher amounts of albuminuria, higher salt intake.
This cohort study demonstrated that an intensive low-salt diet education program attenuated the rate of renal function decline in hypertensive CKD patients independent of its effect on lowering salt intake or albuminuria during the 36 months of follow-up.
饮食调整，尤其是减少盐的摄入，可能是改善慢性肾脏病（CKD）预后的重要非药物策略。
我们进行了一项前瞻性队列研究，以调查强化低盐饮食教育计划是否能有效减缓高血压合并 CKD 患者的肾功能下降速度。
这项队列研究从之前的一项开放性、病例对照、随机临床试验中招募了 171 名参与者，该试验最初纳入了 245 名高血压 CKD 患者，他们被分为强化低盐饮食组或常规教育组。我们评估了肾脏结局，包括每年估算肾小球滤过率（eGFR）的变化率、血清肌酐升高≥50%、eGFR 下降≥30%以及整个研究期间蛋白尿的变化百分比。
两组患者在试验阶段随机分组时的基线特征相似。在整个研究期间，常规组的肾功能下降速度明显较快（0.11±4.63 与-1.53±3.04 mL/min/1.73 m2/年，p=0.01）。强化组血清肌酐升高≥50%的比例为 1.1%，常规组为 8.2%（p=0.025），eGFR 下降≥30%的比例为 3.3%，常规组为 11.1%（p=0.048）。经调整相关因素的 logistic 回归分析，我们发现常规组在整个研究期间血清肌酐和 eGFR 恶化的风险更高。特别是，我们发现强化教育计划在随机分组时具有以下一个或多个特征的患者中保留了 eGFR：年龄较大、女性、肥胖、蛋白质摄入较高、蛋白尿较多、盐摄入量较高。
这项队列研究表明，强化低盐饮食教育计划可减缓高血压 CKD 患者的肾功能下降速度，独立于其降低盐摄入或蛋白尿的作用，在 36 个月的随访期间。
