Patency of arteriovenous fistulas in hemodialysis in French Guiana: influence of vascular flow, climate and clinical factors

Arteriovenous fistula (AVF) is the preferred access for hemodialysis. Achieving one-year patency is crucial to avoid dependence on central venous catheters, which carry significant risks of infection and thrombosis. In French Guiana, a territory marked by precariousness, isolation, and a tropical climate, local determinants of patency are poorly documented. This study aims to evaluate AVF patency at 6 weeks and one year and to identify associated factors. This is a single-center retrospective study including all AVFs created at the Cayenne Hospital Center between 2018 and 2022. Demographic data, comorbidities, vascular parameters, technical characteristics, and season were analyzed. Associations were studied using univariate and multivariate logistic regressions with a multilevel model. The primary endpoint was AVF patency at 6 weeks and 1 year. Among 176 patients, 226 AVFs were created, 92.5% of which were autologous. Patency at one year was 73.7%. Obesity (Body Mass Index ≥ 30) was associated with reduced patency at one year (OR = 0.46; 95% CI [0.24–0.85], p = 0.014) but not at 6 weeks while active smoking reduced patency at one year (OR = 0.34; [0.13–0.89], p = 0.029) but not at 6 weeks. Each previous AVF also reduced the probability of patency (OR = 0.45; [0.27–0.75], p = 0.002 at 6 weeks; OR = 0.54; [0.35–0.84], p = 0.006 at one year). Conversely, a higher mean initial arterial flow significantly improved patency (OR = 3.31; [1.22–8.92], p = 0.018); high flow had an even more pronounced effect (OR = 6.32; [1.63–24.6], p = 0.008); a larger radial diameter was also associated with better outcomes (OR = 2.42; [1.45–4.05], p = 0.001). A season × flow interaction suggested increased vulnerability of AVFs at low flow during the wet season (OR = 0.15; [0.02–1.04], p = 0.05). In French Guiana, AVF patency at one year is primarily determined by vascular parameters (arterial flow and diameter). Modifiable risk factors including obesity and active smoking significantly reduce patency, while multiple previous AVF attempts predict worse outcomes. Exploratory analysis suggests possible seasonal vulnerability in low-flow fistulas, requiring prospective vascular assessment, risk factor optimization, and targeted protocols. Not applicable. This is a retrospective observational cohort study. Trial registration is not required for observational studies according to ICMJE and BMC guidelines. The study was not registered prospectively.