Kidney Week

Abstract: SA-PO377

Predictors of Accelerated Residual Kidney Function Loss on Incremental Hemodialysis

Session Information

• Hemodialysis and Frequent Dialysis: CV and Risk Prediction
  November 05, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
  Abstract Time: 10:00 AM - 12:00 PM

Category: Dialysis

• 701 Dialysis: Hemodialysis and Frequent Dialysis

Authors

• Medeiros, Joana, Hospital de Braga, Braga, Braga, Portugal

Joana Medeiros,

• Ribeiro, Bárbara, Hospital de Braga, Braga, Braga, Portugal

Bárbara Ribeiro,

• Carvalho, Renata, Hospital de Braga, Braga, Braga, Portugal

Renata Carvalho,

• Bastos, José Mário, Hospital de Braga, Braga, Braga, Portugal

José Mário Bastos,

• Costa, Rui Miguel, Hospital de Braga, Braga, Braga, Portugal

Rui Miguel Costa,

• Ramalheiro, Antonio, Hospital de Braga, Braga, Braga, Portugal

Antonio Ramalheiro,

Background

Preservation of residual kidney function (RKF) has been the driving impetus for incremental hemodialysis (IHD). Factors such primary renal disease, comorbidities and haemodialysis prescription may predispose to an earlier loss of residual renal function.

Methods

Retrospective analysis of 37 patients who begun twice-weekly IHD from March 2017 to May 2022 at Braga’s Hospital Dialysis Unit (Portugal). RKF was assessed monthly by residual renal urea clearance and normo-hydrated weight (NHW) was evaluated quarterly by bioelectrical impedance analysis. Inclusion criteria to IHD were: urea clearance ≥3mL/min/1.73m², absence of advanced heart/liver failure and absence of active cancer. Transition on low-flux to high-flux dialysis/haemodiafiltration occurred according to the RKF loss and a maximum ultrafiltration rate of 10mL/kg/hour was determined. An accelerated RKF loss was defined as a loss of at least 25% in the first 3 months.

Results

The mean age was 58±13years, 54.1% were male, and 97% were Caucasian. Diabetic nephropathy (32.4%) was the most common cause of ESRD and arteriovenous fistula was the primary vascular access (54.1%). The Charlson comorbidity index was 4.7±2.2 with 89.2% of patients having hypertension and 40.5% diabetes. Baseline measured glomerular filtration rate (GFR) was 7.5±2.3mL/min/1.72m² and 93.3% had a urinary output greater than 1000mL/day. During the first trimester, accelerated RKF loss occurred in 30% of patients, mainly those with older age, diabetes, Charlson comorbidity index higher than 6 and lower GFR at the baseline. Association with first month intradialytic symptomatic hypovolemia events and dry weigh exceeding NHW (>1kg) was also found. In multivariate analysis, only baseline GFR <7mL/min/1.73m² was a predictor of accelerated decline in RKF (OR 25.4, CI 95% 1.2-530). Loss of RKF at 3 months was significantly associated with lower IHD survival during the first year (28% vs 69%, log Rank test p=0.04).

Conclusion

Factors such as age, comorbidities, first month intradialytic complications and unadjusted dry weigh prescription may influence the rate of RKF loss. Moreover, lower baseline GFR was an independent predictor of accelerated decline in RKF. Late referral to IHD or accelerated loss RKF trend that begun in pre dialysis stages may explain these findings.