title: Metabolic Acidosis and Long-Term Clinical Outcomes in Kidney Transplant Recipients.
abstract: Metabolic acidosis (MA), indicated by low serum total CO2(TCO2) concentration, is a risk factor for mortality and progressive renal dysfunction in CKD. However, the long-term effects of MA on kidney transplant recipients (KTRs) are unclear. We conducted a multicenter retrospective cohort study of 2318 adult KTRs, from January 1, 1997 to March 31, 2015, to evaluate the prevalence of MA and the relationships between TCO2concentration and clinical outcomes. The prevalence of low TCO2concentration (<22 mmol/L) began to increase in KTRs with eGFR<60 ml/min per 1.73 m2and ranged from approximately 30% to 70% in KTRs with eGFR<30 ml/min per 1.73 m2Multivariable Cox proportional hazards models revealed that low TCO2concentration 3 months after transplant associated with increased risk of graft loss (hazard ratio [HR], 1.74%; 95% confidence interval [95% CI], 1.26 to 2.42) and death-censored graft failure (DCGF) (HR, 1.66; 95% CI, 1.14 to 2.42). Cox regression models using time-varying TCO2concentration additionally demonstrated significant associations between low TCO2concentration and graft loss (HR, 3.48; 95% CI, 2.47 to 4.90), mortality (HR, 3.16; 95% CI, 1.77 to 5.62), and DCGF (HR, 3.17; 95% CI, 2.12 to 4.73). Marginal structural Cox models adjusted for time-varying eGFR further verified significant hazards of low TCO2concentration for graft loss, mortality, and DCGF. In conclusion, MA was frequent in KTRs despite relatively preserved renal function and may be a significant risk factor for graft failure and patient mortality, even after adjusting for eGFR.
authors.affiliation: Departments of Biomedical Sciences.
authors.forename: Seokwoo
authors.initials: S
authors.lastname: Park
authors.affiliation: Internal Medicine, and.
authors.forename: Eunjeong
authors.initials: E
authors.lastname: Kang
authors.affiliation: Departments of Biomedical Sciences.
authors.forename: Sehoon
authors.initials: S
authors.lastname: Park
authors.affiliation: Internal Medicine, and.
authors.forename: Yong Chul
authors.initials: YC
authors.lastname: Kim
authors.affiliation: Internal Medicine, and.
authors.forename: Seung Seok
authors.initials: SS
authors.lastname: Han
authors.affiliation: Surgery, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jongwon
authors.initials: J
authors.lastname: Ha
authors.affiliation: Internal Medicine, and.
authors.forename: Dong Ki
authors.initials: DK
authors.lastname: Kim
authors.affiliation: Internal Medicine, and.
authors.forename: Sejoong
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine and.
authors.forename: Su-Kil
authors.initials: SK
authors.lastname: Park
authors.affiliation: Division of Kidney Transplantation, Department of Surgery, Asan Medical Center and University of Ulsan College of Medicine, Seoul, Korea; and.
authors.forename: Duck Jong
authors.initials: DJ
authors.lastname: Han
authors.affiliation: Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul, Korea.
authors.forename: Chun Soo
authors.initials: CS
authors.lastname: Lim
authors.affiliation: Departments of Biomedical Sciences.
authors.forename: Yon Su
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul, Korea nephrolee@gmail.com gskyh@amc.seoul.kr.
authors.forename: Jung Pyo
authors.initials: JP
authors.lastname: Lee
authors.affiliation: Division of Kidney Transplantation, Department of Surgery, Asan Medical Center and University of Ulsan College of Medicine, Seoul, Korea; and nephrolee@gmail.com gskyh@amc.seoul.kr.
authors.forename: Young Hoon
authors.initials: YH
authors.lastname: Kim
mesh_terms: D000138:Acidosis / Q000453:epidemiology*; D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology*; D015995:Prevalence; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
keywords: acidosis; chronic graft deterioration; glomerular filtration rate; kidney transplantation; mortality; transplant recipients