Fatores associados à acidose metabólica: uma comparação entre pacientes com doença renal crônica em diálise peritoenal e em hemodiálise

Abstract

Background: Metabolic acidosis is not completely corrected by dialysis methods and is associated with nutritional, bone, and survival in this population. The use of phosphate chelators, management of bicarbonate replacement, and patient profile may explain differences in prevalence and risk factors for acidosis when comparing dialysis methods. However, there are scarce data in the literature to support these hypotheses. Therefore, we conducted a study to compare factors related to acidosis in a group of patients on hemodialysis and peritoneal dialysis. Methods: This was a cross-sectional study that included prevalent patients on renal replacement therapy, with stage 5 kidney disease, in July 2020. data were obtained from the electronic medical record at the nephrology service at Hospital das Clínicas, University of São Paulo ( HCFMUSP). For analysis, clinical, demographic, and laboratory data were included, in addition to medical prescriptions. The prescription of the sevelamer hydrochloride was checked individually with the patients and compared with the electronic prescription. We defined acidosis as bicarbonate <22 mEq / l, considering values before the session for patients on hemodialysis. Results: 145 patients were included, with an average age of 47  16 years, most of them male and white, 15% diabetic, 25% on peritoneal dialysis. Approximately 52.3% of patients using Sevelamer phosphorus chelator use a lower than prescribed dose, but we did not observe any impact of the sevelamer use on serum bicarbonate. Acidotic patients (48.3% of the sample) had been on a long time on hemodialysis, had higher creatinine, higher phosphorus, and a tendency to lower serum calcium. In hemodialysis, another factor associated with acidosis was the bicarbonate concentration in the dialysis bath, which was higher in the group of patients with acidosis. In logistic regression analysis, the presence of acidosis among patients on hemodialysis and peritoneal dialysis was independently associated with higher creatinine (relative risk 1.12, CI = 1.12-1.47, p = 0.0001), in a model adjusted for sex, bath bicarbonate, calcium, phosphorus, and dialysis time. Conclusion: Metabolic acidosis is common in both hemodialysis and peritoneal dialysis. High levels of serum creatinine configured as an independent marker of the presence of acidosis, maybe reflecting a better nutritional profile of these patients.