Effect of Active Smoking on Outcomes of Arteriovenous Fistulas and Grafts for Hemodialysis Access

In the present study, we evaluated the effect of active smoking on the outcomes of arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs) for hemodialysis access in a large population-based cohort of patients. A retrospective cohort study of all patients with surgical dialysis access in the U.S. renal database system (2007-2015). We used χ2 tests, Student t tests, Kaplan-Meier analysis, log-rank tests, and multivariable logistic and Cox regression analyses were used to evaluate the maturation, interventions, patency, infections, and mortality. The study population included 381,622 patients with 303,307 AVFs (79.5%) and 78,315 prosthetic grafts (20.5%) placed in 22,515 active smokers (5.9%) and 359,107 nonsmokers (94.1%). No significant difference was found in maturation for the smokers compared with the nonsmokers who had received an AVF (adjusted hazard ratio [aHR], 1.01; 95% confidence interval, 0.98-1.03; P = .57) or AVG (aHR, 0.99; 95% CI, 0.95-1.04; P = .83). Comparing smokers and nonsmokers, the primary patency at 5 years was 18.8% and 21.2% (P < .001) for AVFs and 10.2% and 9.9% (P = .026) for AVGs, respectively. Primary-assisted patency at 5 years was 34% and 36.8% (P < .001) for AVF and 17.5% and 18% (P = .25) for AVG between smokers and nonsmokers, respectively. The corresponding secondary patency at 5 years was 43.5% and 46.5% (P < .001) for AVF and 34.8% vs 35.1% (P = .70) for AVG. A decrease was found in primary (aHR, 0.97; 95% CI, 0.95-0.99; P = .001), primary-assisted (aHR, 0.97; 95% CI, 0.95-0.99; P = .019), and secondary (aHR, 0.97; 95% CI, 0.95-0.99; P = .007) patency for smokers compared with nonsmokers who had received an AVF. A decrease was found in primary patency (aHR, 0.96; 95% CI, 0.93-0.99; P = .033) for smokers compared with nonsmokers who had received an AVG. No difference was found in primary-assisted patency, secondary patency, or severe AVG infection between the two groups. A 23% increase was found in patient mortality for smokers relative to nonsmokers who had received an AVF (aHR, 1.23; 95% CI, 1.20-1.25; P < .001) and a 16% increase for AVG recipients (aHR, 1.16; 95% CI, 1.11-1.21; P < .001). In this population-based cohort of hemodialysis patients, smoking was associated with a decrease in patient survival and access patency. We found no association between smoking and AVF or AVG access maturation or severe prosthetic graft infection. These outcomes support the recommendation for smoking cessation for these patients.