Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia, Katowice, Poland.
Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia, Katowice, Poland,
Kidney Blood Press Res. 2020;45(5):702-712. doi: 10.1159/000508476. Epub 2020 Aug 14.
Results of both experimental and clinical studies suggest that metabolic acidosis (MA) contributes to the progression of chronic kidney disease (CKD) and mortality in CKD patients. It is unknown whether the same relationship exists in kidney transplantation (KTx) patients. The aim of this observational study was to examine this relationship between MA and both mortality and renal outcomes in patients after KTx.
Four hundred eighty-six (290 male; 196 female) patients aged 48 ± 12 years, at least 1 year after KTx, were analyzed. Blood HCO3- was measured, and patients were then observed over 3 years. MA was defined as the blood HCO3- concentration <22 mmol/L. The end points of survival analysis were death and initiation of dialysis therapy. In patients who did not reach the above-mentioned end points, the difference between final (after 3 years of follow-up) and initial estimated glomerular filtration rate (eGFR) was calculated.
MA was initially diagnosed in 57 (12%) patients after KTx. Three-year patient survival was 89.5% in the MA group and 97.4% in the non-MA group (p = 0.001). Three-year graft survival was 73.7% for patients with MA and 93.0% for patients without MA (p < 0.001). In patients with MA who did not reach study end points, blood bicarbonate concentration at baseline correlated positively with a change in eGFR (R = 0.48, p = 0.002, n = 36). Such a correlation was not found in patients without MA (n = 388).
(1) MA significantly increases the risk of mortality in patients after KTx. (2) The intensity of MA may be associated with progression of transplanted kidney dysfunction in KTx patients.
实验和临床研究的结果表明，代谢性酸中毒（MA）会促进慢性肾脏病（CKD）患者的病情进展和死亡。在肾移植（KTx）患者中是否存在同样的关系尚不清楚。本观察性研究的目的是探讨 MA 与 KTx 后患者的死亡率和肾脏结局之间的关系。
共分析了 486 名（290 名男性；196 名女性）年龄 48 ± 12 岁、KTx 后至少 1 年的患者。测量血液 HCO3-，并对患者进行了 3 年的观察。MA 的定义为血液 HCO3-浓度<22mmol/L。生存分析的终点为死亡和开始透析治疗。对于未达到上述终点的患者，计算最终（随访 3 年后）和初始估算肾小球滤过率（eGFR）之间的差值。
KTx 后有 57 名（12%）患者最初被诊断为 MA。MA 组的 3 年患者生存率为 89.5%，非 MA 组为 97.4%（p=0.001）。MA 组患者的 3 年移植物存活率为 73.7%，而非 MA 组为 93.0%（p<0.001）。在未达到研究终点的 MA 患者中，基线时血液碳酸氢盐浓度与 eGFR 变化呈正相关（R=0.48，p=0.002，n=36）。在无 MA 的患者（n=388）中未发现这种相关性。
（1）MA 显著增加了 KTx 后患者的死亡风险。（2）MA 的强度可能与 KTx 患者移植肾功能障碍的进展有关。
