Bicarbonate ineffectiveness for kidney transplant

Nilufar Mohebbi and colleagues1Mohebbi N Ritter A Wiegand A et al.Sodium bicarbonate for kidney transplant recipients with metabolic acidosis in Switzerland: a multicentre, randomised, single-blind, placebo-controlled, phase 3 trial.Lancet. 2023; 401: 557-567Summary Full Text Full Text PDF PubMed Scopus (0) Google Scholar reported that correction of metabolic acidosis with sodium bicarbonate for more than 2 years failed to improve the estimated glomerular filtration rate in adult recipients of renal transplants. The results of this trial differ from previous studies, in which administration of sodium bicarbonate improved renal function in patients with chronic kidney diseases.2Hultin S Johnson DW Badve SV Recent evidence on the effect of treatment of metabolic acid on the progression of kidney disease.Curr Opin Nephrol Hypertens. 2021; 30: 467-473Crossref PubMed Scopus (3) Google Scholar The population in Mohebbi and colleagues’ study was predominantly White (202 [84%] of 240 participants) and only 13–22% of the population were Black. Similarly, in previous studies on chronic kidney diseases other than renal transplantation,3Mahajan A Simoni J Sheather SJ Broglio KR Rajab MH Wesson DE Daily oral sodium bicarbonate preserves glomerular filtration rate by slowing its decline in early hypertensive nephropathy.Kidney Int. 2010; 78: 303-309Summary Full Text Full Text PDF PubMed Scopus (297) Google Scholar, 4Goraya N Simoni J Jo CH Wesson DE Treatment of metabolic acidosis in patients with stage 3 chronic kidney disease with fruits and vegetables or oral bicarbonate reduces urine angiotensinogen and preserves glomerular filtration rate.Kidney Int. 2014; 86: 1031-1038Summary Full Text Full Text PDF PubMed Scopus (273) Google Scholar White participants made up 53–63% of the populations. Since the risk of chronic kidney diseases varies by race, and Black people are 3–4 times more at risk than White people,5Assari S Racial disparities in chronic kidney diseases in the United States; a pressing public health challenge with social, behavioral and medical causes.J Nephropharmacol. 2015; 5: 4-6Google Scholar Black people might be more likely to respond to bicarbonate therapy, and the reverse might be true for White people. Given this information, it is difficult to establish whether the finding that sodium bicarbonate was ineffective in recipients of renal transplants was due to the transplantation procedures, or was biased due to the predominantly White population. We declare no competing interests. Sodium bicarbonate for kidney transplant recipients with metabolic acidosis in Switzerland: a multicentre, randomised, single-blind, placebo-controlled, phase 3 trialIn adult kidney transplant recipients, correction of metabolic acidosis by treatment with sodium bicarbonate over 2 years did not affect the decline in estimated GFR. Thus, treatment with sodium bicarbonate should not be generally recommended to preserve estimated GFR (a surrogate marker for graft function) in kidney transplant recipients with chronic kidney disease who have metabolic acidosis. Full-Text PDF Bicarbonate ineffectiveness for kidney transplant – Authors' replyWe thank Michioki Endo andMasahiro Kami for their Correspondence and for raising an important question: whether the risk of chronic kidney disease progression and the response to bicarbonate treatment in metabolic acidosis might depend on the patients’ race. Generalisability of the Swiss Preserve-Transplant Study (PTS) results is limited due to the mainly White study population (84·2%), as stated in the Article,1 and only 3·8% of patients were either African or African American. Full-Text PDF