DIURETIC USE IN HEMODIALYSIS PATIENTS: BENEFIC ASSOCIATION WITH RESIDUAL RENAL FUNCTION AND ALL-CAUSE MORTALITY

Abstract Background and Aims In patients with end-stage renal disease (ESRD) on hemodialysis, the preservation of residual kidney function may result in a diversity of benefits in terms of survival and quality of life. The control of fluid and electrolyte homeostasis may play an important role in this setting. Elevated predialysis serum potassium is a common electrolyte disturbance that may worsen patient’s outcomes. Our aim was to study the impact of furosemide therapy in predialysis serum potassium levels, indicators of estimated residual renal function, and inflammatory markers, in ESRD patients under hemodialysis; moreover, we aimed to study the impact of furosemide-associated changes on mortality rate. Method A cross-sectional study was carried out on 289 adult patients on chronic dialysis therapy (hemodiafiltration and high flux hemodialysis). Patients were divided in 2 groups: the diuretic group (DG, n=116; 120.0 (IQR: 80-160) mg/daily median furosemide dose) and the non-diuretic group (NDG, n = 173), in which patients did not use furosemide. A large set of data was analyzed, encompassing hematological data, serum electrolyte parameters, inflammatory markers, dialysis adequacy, and biomarkers of residual kidney function. A 2-year follow up study was also performed by registering events of death (all-cause mortality). Results The DG patients, compared with NDG patients, presented: significantly lower predialysis serum potassium; more favorable blood biomarkers of kidney function - lower β-trace protein, cystatin C, creatinine and urea; greater residual glomerular filtration rate derived from equations with cystatin C, creatinine and creatinine–cystatin C; lower inflammation (significantly lower levels of high-sensitivity C-reactive protein); intradialytic ultrafiltration volume (L) was similar for the two groups. Mortality was significantly lower for DG patients, compared with NDG (13.6% versus 24.7%; P=0.029). Conclusion In ESRD patients under chronic dialysis, we found a significant association between current diuretic therapy and lower predialysis serum potassium levels, more favorable biomarkers of kidney function and a decreased inflammatory response that seem to contribute to a higher survival rate. Acknowledgments: The work was supported by UIDB/04378/2020 with funding from FCT/MCTES through national funds, by North Portugal Regional Coordination and Development Commission (CCDR-N)/NORTE2020/Portugal 2020 (Norte-01-0145-FEDER-000024) and by REQUIMTE-Rede de Química e Tecnologia-Associação in the form of a researcher (S. Rocha) – project Dial4Life co-financed by FCT/MCTES (PTDC/MEC-CAR/31322/2017) and FEDER/COMPETE 2020 (POCI-01-0145-FEDER-031322).