Harold Simmons Center for Chronic Disease Research and Epidemiology, Division of Nephrology, Hypertension, and Kidney Transplantation, University of California Irvine, Orange, CA, USA.
Tibor Rubin Veterans Affairs Long Beach Health Center, Long Beach, CA, USA.
Am J Clin Nutr. 2022 Oct 6;116(4):1123-1134. doi: 10.1093/ajcn/nqac215.
In healthy adults, higher dietary potassium intake is recommended given that potassium-rich foods are major sources of micronutrients, antioxidants, and fiber. Yet among patients with advanced kidney dysfunction, guidelines recommend dietary potassium restriction given concerns about hyperkalemia leading to malignant arrhythmias and mortality.
Given sparse data informing these recommendations, we examined associations of dietary potassium intake with mortality in a nationally representative cohort of adults from the NHANES.
We examined associations between daily dietary potassium intake scaled to energy intake (mg/1000 kcal), ascertained by 24-h dietary recall, and all-cause mortality among 37,893 continuous NHANES (1999-2014) participants stratified according to impaired and normal kidney function (estimated glomerular filtration rates <60 and ≥60 mL · min-1 · 1.73 m-2, respectively) using multivariable Cox models. We also examined the impact of the interplay between dietary potassium, source of potassium intake (animal- compared with plant-based sources), and coexisting macronutrient and mineral consumption upon mortality.
Among participants with impaired and normal kidney function, the lowest tertile of dietary potassium scaled to energy intake was associated with higher mortality (ref: highest tertile) [adjusted HR (aHR): 1.18; 95% CI: 1.02, 1.38 and aHR: 1.17; 95% CI: 1.06, 1.28, respectively]. Compared with high potassium intake from plant-dominant sources, participants with low potassium intake from animal-dominant sources had higher mortality irrespective of kidney function. Among participants with impaired kidney function, pairings of low potassium intake with high protein, low fiber, or high phosphorus consumption were each associated with higher death risk.
Lower dietary potassium scaled to energy intake was associated with higher mortality, irrespective of kidney function. There was also a synergistic relation of higher potassium intake, plant-based sources, and macronutrient/mineral consumption with survival. Further studies are needed to elucidate pathways linking potassium intake and coexisting dietary factors with survival in populations with and without chronic kidney disease.
在健康成年人中，建议增加富含钾的食物摄入，因为这些食物是微量营养素、抗氧化剂和纤维的主要来源。然而，对于肾功能严重受损的患者，由于担心高钾血症导致恶性心律失常和死亡，指南建议限制钾的摄入。
鉴于这些建议的数据有限，我们通过 NHANES 的全国代表性成年人队列研究，检查了饮食钾摄入量与死亡率之间的关系。
我们通过 24 小时膳食回顾来评估每日饮食钾摄入量与能量摄入的比例（mg/1000 千卡）与全因死亡率之间的关系，这项研究纳入了根据肾小球滤过率（eGFR）<60 和≥60ml/min·1.73m-2 分层的 37893 名连续 NHANES（1999-2014）参与者，使用多变量 Cox 模型。我们还研究了饮食钾、钾摄入来源（动物源与植物源）以及共存宏量营养素和矿物质摄入之间相互作用对死亡率的影响。
在肾功能受损和正常的参与者中，能量摄入标准化的饮食钾最低三分位与死亡率较高相关（参考：最高三分位）[调整后的 HR（aHR）：1.18；95%CI：1.02，1.38 和 aHR：1.17；95%CI：1.06，1.28]。与高钾摄入来自植物源相比，无论肾功能如何，低钾摄入来自动物源的参与者死亡率更高。在肾功能受损的参与者中，低钾摄入与高蛋白、低纤维或高磷摄入的组合均与更高的死亡风险相关。
能量摄入标准化的饮食钾摄入量较低与死亡率较高相关，与肾功能无关。钾摄入较高、植物源、宏量营养素/矿物质摄入的协同作用与生存相关。需要进一步的研究来阐明在有或没有慢性肾脏病的人群中，钾摄入和共存饮食因素与生存之间的关联途径。
