The Role of Skin Sodium Accumulation in Chronic Kidney Disease

"Each patient will receive 1 tablet of hydrochlorothiazide 12.5mg once a day for the first 3 weeks of the drug cycle. If clinical and biochemical parameters allow, the dosage is doubled to 2 tablets of hydrochlorothiazide 12.5mg once daily for the following 3 weeks.~If the laboratory results and clinical parameters do not allow dose intensification, the initial dosage will be continued during the second half of the drug cycle."

"Each patient will receive 1 tablet of spironolacton 12.5mg once a day for the first 3 weeks of the drug cycle. If clinical and biochemical parameters allow, the dose is doubled to 2 tablets of spironolacton 12.5mg once daily for the following 3 weeks.~If the laboratory results and clinical parameters do not allow dose intensification, the initial dosage will be continued during the second half of the drug cycle."

"Each patients will receive 1 tablet of lercanidipine 10mg once a day for the first 3 weeks of the drug cycle. If clinical and biochemical parameters allow, the dose is doubled to 2 tablets of lercanidipine 10mg once daily for the following 3 weeks.~If the laboratory results and clinical parameters do not allow dose intensification, the initial dosage will be continued during the second half of the drug cycle."

The patients will receive a 2-week high sodium diet. The patients will receive dietary advice to achieve this goal of \>200mmol/l sodium (\>12g salt) intake per day.

The patients will receive a 2-week low sodium diet. The patients will receive dietary advice to achieve this goal of \<50mmol/l sodium (\<3g salt) intake per day.

During the increased water intake period, the patients will be instructed to drink 1 L more than their mean 24-hour urine volume at screening and baseline.

During this part of the intervention, the patients will be instructed to maintain their habitual water intake.