Abstract: 【Abstract】Objective To explore the effect of interdialytic weight gain (IDWG) on the dysfunction of arteriovenous fistula (AVF) in maintenance hemodialysis (MHD) patients. Methods A total of 577 MHD patients treated in Guangdong Provincial People’s Hospital during the period from 2009 to 2019 were recruited for a retrospective and cohort study. Clinical data of the patients before entering the study were collected. The average IDWG was calculated based on the predialysis body weight and dry weight in every dialysis session in 2009. The observation index was AVF dysfunction. Results The MHD patients were divided into IDWG ≤4% group and IDWG >4% group. The two groups of confounding variables were controlled by propensity score matching method and a total of 414 patients completed 1:1 matching. Before and after the matching, the AVF dysfunction in IDWG >4% group was higher than that in IDWG≤4% group (before matching: 34.2% vs. 65.8%, χ2=5.718, P=0.017; after matching: 14.5% vs. 22.7%, χ2=4.611, P=0.032). Binary logistic regression analysis showed that age (OR=3.393, 95% CI 1.861～6.184, P<0.001), IDWG (OR=1.967, 95% CI 1.157～3.347, P=0.013), serum albumin (OR=1.759, 95% CI 1.034～2.990, P=0.037) and left ventricular mass index (OR=1.008, 95% CI 1.002～1.013, P=0.010) were the independent risk factors for AVF dysfunction. Conclusion
IDWG over 4% was an important risk factor for AVF dysfunction in MHD patients, especially in patients >60 years old, and with serum albumin <35g/L and higher left ventricular mass index.

Key words: Hemodialysis, Interdialytic weight gain, Arteriovenous fistula, Dysfunction, Propensity score matching