2826 The Charlson Comorbidity Index in Registry-Based Research for Survival of Vascular Access

Abstract Background and Aims Several studies have reported higher haemodialysis survival in women; however, the influence of gender on arteriovenous fistula survival has not been extensively studied. For this reason, our aim is to estimate the prevalence of arteriovenous fistulae according to gender, adjusted by the Charlson comorbidity index. Method Retrospective study in patients on haemodialysis programme, by consulting electronic records over a period of 35 months. Demographic variables, primary and secondary patency events were included. The population was categorised on the basis of the Charlson Index and gender. Statistical analysis was performed using Kaplan Meyer survival curves to contrast the impact of comorbidities on the different patency events. Results 52 patients were evaluated, with a mean age of 70.7 ± 1.57 years, 69.2% men, 30.8% women, 42.3% diabetic, Charlson with a median of 7 (6.5 - 7.73), 98.1% had a native fistula, being more frequent the location in the humeral head (63.5%) and predominantly in the left upper limb (65.4% ). 21.2% of patients required some intervention on their AVF. The time required to achieve an event in both primary patency and secondary patency was longer in patients with a Charlson Index less than or equal to 7, and this was statistically significant (Log Rank Test (Mantel-Cox): primary patency p=0.003 and secondary patency p=0.002). In the group of women with a Charlson comorbidity index less than or equal to 7, mean survival for primary and secondary patency was even higher than in all patients, with statistical significance (Log Rank Test (Mantel-Cox ): primary patency p=0.005 and secondary patency p=0.008), a situation not repeated in men where no significant differences in survival were found when analysed according to the Charlson index. Conclusion The Charlson index in our population is a significant factor in the survival of AVFs in women.