The impact of high serum bicarbonate levels on mortality in hemodialysis patients.
- Author:
Kyung Yoon CHANG
1
;
Hyung Wook KIM
;
Woo Jeong KIM
;
Yong Kyun KIM
;
Su Hyun KIM
;
Ho Chul SONG
;
Young Ok KIM
;
Dong Chan JIN
;
Euy Jin CHOI
;
Chul Woo YANG
;
Yong Lim KIM
;
Nam Ho KIM
;
Shin Wook KANG
;
Yon Su KIM
;
Young Soo KIM
Author Information
- Publication Type:Original Article
- Keywords: Renal dialysis; Bicarbonates; Alkalosis; Mortality
- MeSH: Alkalosis; Bicarbonates; Carbon Dioxide; Cohort Studies; Follow-Up Studies; Humans; Kaplan-Meier Estimate; Kidney Failure, Chronic; Korea; Mortality*; Proportional Hazards Models; Renal Dialysis*
- From:The Korean Journal of Internal Medicine 2017;32(1):109-116
- CountryRepublic of Korea
- Language:English
- Abstract: BACKGROUND/AIMS: The optimal serum bicarbonate level is controversial for patients who are undergoing hemodialysis (HD). In this study, we analyzed the impact of serum bicarbonate levels on mortality among HD patients. METHODS: Prevalent HD patients were selected from the Clinical Research Center registry for End Stage Renal Disease cohort in Korea. Patients were categorized into quartiles according to their total carbon dioxide (tCO₂) levels: quartile 1, a tCO₂ of < 19.4 mEq/L; quartile 2, a tCO₂ of 19.4 to 21.5 mEq/L; quartile 3, a tCO₂ of 21.6 to 23.9 mEq/L; and quartile 4, a tCO₂ of ≥ 24 mEq/L. Cox regression analysis was used to calculate the adjusted hazard ratio (HR) and confidence interval (CI) for mortality. RESULTS: We included 1,159 prevalent HD patients, with a median follow-up period of 37 months. Kaplan-Meier analysis revealed that the all-cause mortality was significantly higher in patients from quartile 4, compared to those from the other quartiles (p = 0.009, log-rank test). The multivariate Cox proportional hazard model revealed that patients from quartile 4 had significantly higher risk of mortality than those from quartile 1, 2 and 3, after adjusting for the clinical variables in model 1 (HR, 1.99; 95% CI, 1.15 to 3.45; p = 0.01) and model 2 (HR, 1.82; 95% CI, 1.03 to 3.22; p = 0.04). CONCLUSIONS: Our data indicate that high serum bicarbonate levels (a tCO₂ of ≥ 24 mEq/L) were associated with increased mortality among prevalent HD patients. Further effort might be necessary in finding the cause and correcting metabolic alkalosis in the chronic HD patients with high serum bicarbonate levels.
