盐摄入量对非透析慢性肾脏病患者和肾脏生存的预测作用：老年与年轻患者在肾病科护理下的竞争风险分析。

Predictive effect of salt intake on patient and kidney survival in non-dialysis CKD: competing risk analysis in older versus younger patients under nephrology care.

机构信息

Nefrology Unit, University of Campania "Luigi Vanvitelli", Naples, Italy.

Division of Nephrology, "Magna Grecia" University, Catanzaro, Italy.

出版信息

Nephrol Dial Transplant. 2021 Dec 2;36(12):2232-2240. doi: 10.1093/ndt/gfaa252.

DOI:10.1093/ndt/gfaa252

PMID:33877358

Abstract

BACKGROUND

The optimal level of salt intake remains ill-defined in non-dialysis chronic kidney disease (CKD) patients under regular nephrology care. This unanswered question becomes critical in older patients who are exposed to higher risk of worsening of cardiorenal disease due to volemic changes.

METHODS

In this pooled analysis of four prospective studies in CKD, we compared the risk of all-cause mortality and end-stage kidney disease (ESKD) between patients ≤65 and >65 years of age stratified by salt intake level (<6, 6-8 and >8 g/day) estimated from two measurements of 24-h urinary sodium.

RESULTS

The cohort included 1785 patients. The estimated glomerular filtration rate was 37 ± 21 mL/min/1.73 m2 overall, 41 ± 25 in younger patients and 34 ± 16 in older patients (P < 0.001). The median 24-h urinary sodium excretion was 143 mEq [interquartile range (IQR) 109-182] in all, 147 (112-185) in younger patients and 140 (106-179) in older patients (P = 0.012). Salt intake was ≤6, 6-8 and >8 g sodium chloride/day in 21.9, 26.2 and 52.0% of older patients and 18.6, 25.2 and 56.2% in younger patients, respectively (P = 0.145). During a median follow-up of 4.07 years we registered 383 ESKD and 260 all-cause deaths. In the whole cohort, the risks of ESKD and all-cause death did not differ by salt intake level. In older patients, ESKD risk [multi-adjusted hazard ratio (HR) and 95% confidence interval (CI)] was significantly lower at salt intakes of 6-8 g/day [HR 0.577 (95% CI 0.361-0.924)] and >8 g/day [HR 0.564 (95% CI 0.382-0.833)] versus the reference group (<6 g/day). Mortality risk was higher in older versus younger patients, with no difference across salt intake categories. No effect of salt intake on ESKD and mortality was observed in younger patients.

CONCLUSIONS

CKD patients under nephrology care show a moderate salt intake (8.4 g/day) that is lower in older versus younger patients. In this context, older patients are not exposed to higher mortality across different levels of salt intake, while salt intake <6 g/day poses a greater risk of ESKD.

摘要

背景

在接受常规肾脏病学护理的非透析慢性肾脏病（CKD）患者中，盐摄入量的最佳水平仍未明确。对于因血容量变化而使心脏-肾脏疾病恶化风险更高的老年患者来说，这个未解决的问题变得尤为关键。

方法

在这项对四项 CKD 前瞻性研究的汇总分析中，我们比较了盐摄入量水平（<6、6-8 和 >8g/天）估计值（根据 24 小时尿钠的两次测量得出）<65 岁和 >65 岁患者的全因死亡率和终末期肾病（ESKD）风险。

结果

队列包括 1785 名患者。估计肾小球滤过率（eGFR）总体为 37±21mL/min/1.73m2，年轻患者为 41±25mL/min/1.73m2，老年患者为 34±16mL/min/1.73m2（P<0.001）。所有患者的 24 小时尿钠排泄中位数为 143mEq[四分位距（IQR）109-182]，年轻患者为 147（112-185），老年患者为 140（106-179）（P=0.012）。<6、6-8 和 >8g 氯化钠/天的盐摄入量分别占老年患者的 21.9%、26.2%和 52.0%，年轻患者的 18.6%、25.2%和 56.2%（P=0.145）。在中位随访 4.07 年期间，我们登记了 383 例 ESKD 和 260 例全因死亡。在整个队列中，盐摄入量水平与 ESKD 和全因死亡风险无关。在老年患者中，盐摄入量为 6-8g/天时[多变量调整后的风险比（HR）和 95%置信区间（CI）]ESKD 风险显著降低[HR 0.577（95%CI 0.361-0.924）]和 >8g/天时[HR 0.564（95%CI 0.382-0.833）]与参考组（<6g/天）相比。与年轻患者相比，老年患者的死亡率更高，但在不同盐摄入量类别中无差异。在年轻患者中，盐摄入量对 ESKD 和死亡率没有影响。