Chronic Disease Innovation Centre, Winnipeg, MB, Canada.
Department of Community Health Sciences, University of Manitoba, Max Rady College of Medicine, Winnipeg, MB, Canada.
BMC Nephrol. 2023 Oct 13;24(1):301. doi: 10.1186/s12882-023-03354-4.
Potassium regulation in the body is primarily done in the kidney. In addition to this, hyperkalemia, occurs in approximately 10% of individuals with chronic kidney disease (CKD) and is associated with elevated all-cause mortality. Individuals with CKD are often told to restrict dietary potassium (K), however, this recommendation is based on low quality evidence. Reduced quality of life, limited dietary choices and nutritional deficiencies are all potential negative outcomes that may occur when restricting dietary K in CKD patients. There is a need for randomized controlled trials investigating the impact of dietary K modification on serum K concentrations in people with CKD.
A randomized 2-period crossover design comparing a liberalized K fruit and vegetable diet where participants will be required to consume ~ 3500 mg of dietary K daily, to a standard K restricted diet where participants will be required to consume < 2000 mg of dietary K daily. All participants will begin on a liberalized K run-in period for 2 weeks where they will receive fruit and vegetables home deliveries and for safety will have clinical chemistry, including serum potassium measurements taken after 1 week. Participants will then be randomized into either liberalized K or standard K diet for six weeks and then crossover to the other intervention for another 6 weeks after a 2-week washout period.
30 male and female CKD outpatients, ≥ 18 years of age, who have an estimated glomerular filtration rate (eGFR) between 15 and 45 ml/min/1.73m and serum K between 4.5 and 5.5 mEq/L. This design would have greater than 80% power to detect a difference of 0.35 mEq/L serum K between groups. Anthropometric measurements, clinical chemistry, dietary recalls, physical function assessments, as well as a quality of life assessments will also be measured in this trial. These findings will provide high quality evidence for, or against, recommendations for dietary K restriction in individuals living with CKD. The removal of K restriction could provide individuals living with CKD more dietary choice leading to improved dietary status and quality of life.
This trial has received approval from the University of Manitoba Research Ethics board (HS25191 (B2021:104)).
人体的钾调节主要在肾脏中进行。此外，大约 10%的慢性肾脏病 (CKD) 患者会出现高钾血症，并且与全因死亡率升高有关。CKD 患者通常被告知要限制饮食中的钾 (K)，但这一建议的依据是质量较低的证据。降低生活质量、饮食选择受限和营养缺乏等，都是 CKD 患者限制饮食 K 时可能出现的潜在负面结果。因此，有必要进行随机对照试验，研究饮食 K 改变对 CKD 患者血清 K 浓度的影响。
本研究采用随机 2 期交叉设计，比较了一种宽松的 K 水果和蔬菜饮食，参与者需要每天摄入约 3500 毫克的饮食 K，以及一种标准的 K 限制饮食，参与者需要每天摄入 <2000 毫克的饮食 K。所有参与者都将开始为期 2 周的宽松 K 预试验期，在此期间，他们将收到水果和蔬菜的送货上门服务，为了安全起见，将在第 1 周后进行临床化学检查，包括血清钾测量。然后，参与者将被随机分配到宽松 K 或标准 K 饮食组，持续 6 周，然后在 2 周洗脱期后交叉到另一种干预组，再持续 6 周。
30 名年龄在 18 岁及以上的 CKD 门诊患者，估计肾小球滤过率 (eGFR) 在 15 至 45 ml/min/1.73m 之间，血清 K 在 4.5 至 5.5 mEq/L 之间。该设计将有超过 80%的概率检测到两组之间血清 K 差异 0.35 mEq/L。在该试验中还将测量人体测量学指标、临床化学、饮食回忆、身体功能评估以及生活质量评估。这些发现将为饮食 K 限制是否适用于 CKD 患者提供高质量的证据。取消 K 限制可以为 CKD 患者提供更多的饮食选择，从而改善饮食状况和生活质量。
本试验已获得马尼托巴大学伦理委员会的批准（HS25191 (B2021:104)）。
