Socioeconomic Status and Vascular Access Patency in Hemodialysis: Analysis of Korean National Health Insurance Service Data from 2008 to 2019

<b>Background</b>: Socioeconomic status (SES) disparities impact health outcomes, but their effect on vascular access (VA) in hemodialysis patients in Korea remains underexplored. <b>Methods</b>: This study evaluated the association between SES and VA outcomes using National Health Insurance Service data from 2008 to 2019. Incident hemodialysis patients were categorized by insurance status into the health insurance group (HG) and medical aid group (MG). The primary endpoint was VA patency, and the secondary endpoint was all-cause mortality, adjusted for demographics, comorbidities, and lifestyle factors. <b>Results</b>: Among 86,036 patients, the MG (12.1%) was younger at VA creation (60.4 ± 13.5 vs. 63.1 ± 13.6 years, <i>p</i> < 0.001) and had higher rates of comorbidities (all <i>p</i> < 0.05 except cancer). Mortality rates per 100 person-years were higher in the MG (11.66 vs. 9.24 for AVF; 17.94 vs. 16.92 for AVG), as was the total procedure frequency (2.10 vs. 1.87, <i>p</i> < 0.001), despite similar percutaneous angioplasty counts (1.20 vs. 1.24, <i>p</i> = 0.314). <b>Conclusions</b>: Lower SES patients exhibited poorer VA patency and higher mortality rates despite equitable healthcare access and cost coverage in Korea. These findings suggest that non-medical factors, such as adherence to treatment and timely intervention, play a critical role in mitigating these disparities.