Kidney-protective Intervention With Salt Substitute After Kidney Tumor Surgery: a Single-center Randomized Controlled Study

Launched by JINLING HOSPITAL, CHINA · Jul 3, 2025

Keywords

ClinConnect Summary

This clinical trial is studying whether using a salt substitute instead of regular salt can help protect kidney function in people who have had surgery to remove a kidney tumor. After this type of surgery, it’s important to keep the remaining kidney healthy. The study will compare two groups of patients—one using a salt substitute and the other using regular salt—to see if the salt substitute helps improve kidney health over the course of a year. Researchers will also check if using salt substitutes is safe, whether patients are able to stick to the salt substitute diet, and if this type of dietary change is practical for patients after surgery.

People eligible for this study are adults who recently had kidney tumor surgery and have fairly good kidney function before surgery. They should mostly eat home-cooked meals and not have certain other health problems like severe heart disease, uncontrolled diabetes, or existing kidney diseases. Participants will be asked to use either salt substitutes or regular salt while keeping their salt intake within World Health Organization guidelines. They will have regular check-ups, including blood and urine tests, over the next year to monitor kidney function and safety. Participants will also report any health changes during the study. This trial aims to find an easy and safe way to protect kidney health after surgery, which could improve long-term outcomes for patients.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• * Participants must meet all of the following criteria:
• • 1. Voluntary participation with signed informed consent from both the primary participant and all cohabiting family members, with commitment to study procedures and follow-up;
• • 2. Age ≥18 years at enrollment (when signing informed consent), any gender;
• • 3. Diagnosed kidney tumor patients who underwent radical nephrectomy or partial nephrectomy (no restrictions on surgical approach);
• • 4. Preoperative eGFR \>60 ml/min/1.73m² (calculated by CKD-EPI equation);
• • 5. Serum potassium \<4.8 mmol/L;
• • 6. Predominantly home-based dietary habits (\>90% meals prepared at home, assessed via self-report);
• • 7. Normal contralateral renal function at screening;
• 8. Normal cardiopulmonary and hepatic function:
• Exclusion Criteria:
• * Participants will be excluded if they meet any of the following:
• • 1. Participant or cohabiting family members currently using potassium-sparing diuretics or potassium supplements, or prior use of salt substitutes;
• • 2. Post-discharge eGFR \<45 ml/min/1.73m² without significant fluctuation;
• • 3. Comorbid chronic kidney diseases (e.g., diabetic nephropathy, lupus nephritis);
• • 4. Preoperative history of urinary tract obstruction;
• • 5. Cohabiting family member(s) with CKD (eGFR \<45 ml/min/1.73m²);
• • 6. Planned postoperative nephrotoxic medications (e.g., anti-neoplastic agents, immunotherapy);
• • 7. Uncontrolled diabetes (HbA1c ≥12%);
• • 8. Uncontrolled hypertension (seated SBP ≥180 mmHg or DBP ≥110 mmHg), symptomatic hypotension (SBP \<90 mmHg), or clinically evident hypovolemia;
• • 9. Preoperative proteinuria (≥1+ on dipstick);
• • 10. Severe cardiovascular disease (NYHA Class III-IV), gastrointestinal obstruction, or hyperkalemia history;
• • 11. BMI \<18.5 kg/m² or \>30 kg/m²;
• • 12. Participation in another clinical trial ≤30 days before randomization or concurrently;
• • 13. Communication barriers or anticipated non-adherence;
• • 14. Structural/functional urological abnormalities (e.g., duplicated kidneys, polycystic kidneys, renal artery stenosis, stones, BPH) or indwelling catheters;
• • 15. Prior radiotherapy/ablation/surgery on the contralateral kidney;
• • 16. Life expectancy \<6 months (e.g., metastatic renal carcinoma).