Age-based outcomes of autogenous fistulas for hemodialysis access.

BACKGROUND: Hemodialysis (HD) dependence and autogenous fistula use for HD span the spectrum of age. This study examines age-related outcomes of autogenous fistulas for HD access in a large population-based cohort of patients. METHODS: A retrospective cohort study of all patients who initiated HD in the United States Renal Database System (2007-2014). χ2 tests, t tests, Kaplan-Meier, log-rank tests, multivariable logistic, and Cox regression analyses were employed to evaluate access maturation, interventions, patency, and mortality. RESULTS: Of the 303,281 patients studied, 48,892 (16.1%) were younger than 50 years, 55,817 (18.4%) were 50 to 59 years, 79,138 (26.1%) were 60 to 69 years, 75,200 (24.8%) were 70 to 79 years, and 44,234 (14.6%) were 80 years or older. There was a decrease in autogenous fistula maturation with increasing age. Primary patency at 5 years comparing patients <50 vs 50 to 59 vs 60 to 69 vs 70 to 79 vs 80+ years was 24% vs 23% vs 21% vs 20% vs 18% (P < .001). Primary assisted patency at 5 years was 38% vs 40% vs 37% vs 35% vs 33% (P < .001). Secondary patency at 5 years was 48% vs 50% vs 47% vs 45% vs 42% (P < .001). The risk-adjusted analyses revealed a progressive decrease in primary, primary assisted, and secondary patency with increasing age. As expected, patient survival decreased with increasing age. CONCLUSIONS: In this population-based cohort of HD patients, there was a decrease in autogenous fistula maturation, primary patency, primary assisted patency, secondary patency, and patient survival with increasing age. Despite the relative decline in outcomes associated with older age, decisions about arteriovenous access creation in older patients should be individualized, taking overall clinical status and outcomes of alternatives modes of access into consideration.

Impact of Body Mass Index on Outcomes of Autogenous Fistulas for Hemodialysis Access.

BACKGROUND: The prevalence of obesity is increasing in the United States. The treatment of end-stage renal disease (ESRD) via hemodialysis spans the spectrum of body mass index (BMI). This study examines the impact of BMI on outcomes of autogenous fistulas for hemodialysis access in a large population-based cohort of patients. METHODS: A retrospective study of all patients in the prospectively maintained United States Renal Database System who initiated hemodialysis between 2007 and 2014 was performed. Chi-squared test, t-tests, Kaplan-Meier estimates, log-rank tests, multivariable logistic and Cox regression analysis were employed to evaluate access maturation, interventions, patency, and mortality. RESULTS: There were 300,778 patients studied. Of these, 9,394 (3.1%) were underweight, 87,351 (29.1%) were normal weight, 86,101 (28.6%) were overweight, 57,047 (19%) were obese class I, 31,077 (10.3%) were obese class II, and 29,808 (9.9%) were obese class III. There was no significant difference in maturation for patients who were underweight (adjusted hazard ratio [aHR] 0.97, 95% CI 0.89-1.06, P = 0.48), overweight (aHR 1.01, 95% CI 0.97-1.05, P = 0.66), obese class I (aHR 1.05, 95% CI 0.99-1.09, P = 0.22), or obese class II (aHR 1.01, 95% CI 0.94-1.05, P = 0.98 relative to normal weight. However, there was a 6% decrease in maturation for obese class III patients (aHR 0.94, 95% CI 0.89-0.99, P = 0.02) compared to normal weight patients. Primary (aHR 0.93, 95% CI 0.91-0.96, P < 0.001), primary assisted (aHR 0.90, 95% CI 0.88-0.93, P < 0.001), and secondary patency (aHR 0.89, 95% CI 0.86-0.92, P < 0.001) were lower for underweight compared to normal weight patients. There was 8%, 10%, and 7% decrease in primary (aHR 0.92, 95% CI 0.90-0.93, P < 0.001), primary assisted (aHR 0.90, 95% CI 0.88-0.92, P < 0.001), and secondary patency (aHR 0.93, 95% CI 0.91-0.94, P < 0.001) respectively for patients in obese class III compared to patients with normal weight. There was an increase in patient survival with increasing BMI. CONCLUSIONS: In this population-based cohort of hemodialysis-dependent patients, severe obesity was associated with a decrease in fistula maturation. Extremes of BMI were associated with lower patency, but higher BMI was associated with better patient survival. Obese patients nearing ESRD might require earlier referral for arteriovenous fistula (AVF) placement in order to allow for maturation and AVF use at incident hemodialysis.

Outcomes of autogenous fistulas and prosthetic grafts for hemodialysis access in diabetic and nondiabetic patients.

BACKGROUND: This study evaluated the effect of diabetes on outcomes of autogenous fistulas and prosthetic grafts for hemodialysis access in a large population-based cohort of patients. METHODS: A retrospective cohort study was conducted of all patients who initiated hemodialysis in the United States Renal Database System (2007-2014). The χ2 test, Student t-test, Kaplan-Meier analysis, log-rank test, and multivariable logistic and Cox regression analyses were employed to evaluate maturation, interventions, patency, infection, and mortality. RESULTS: The study of 381,622 patients comprised 303,307 (79.5%) autogenous fistulas and 78,315 (20.5%) prosthetic grafts placed in 231,134 (60.6%) diabetic patients and 150,488 (39.4%) nondiabetic patients. There was decrease in maturation for diabetics compared to nondiabetics who received autogenous fistulas (adjusted hazard ratio [aHR], 0.86; 95% confidence interval [CI], 0.83-0.88; P < .001) and prosthetic grafts (aHR, 0.88; 95% CI, 0.83-0.93; P < .001). Comparing diabetics vs nondiabetics, primary patency at 5 years was 19.4% vs 23.5% (P < .001) for autogenous fistulas and 9.1% vs 11.2% (P < .001) for prosthetic grafts. Primary assisted patency at 5 years was 35.2% vs 38.7% (P < .001) for autogenous fistulas and 17.2% vs 19.2% (P = .015) for prosthetic grafts. Secondary patency at 5 years was 44.8% vs 48.6% (P < .001) for autogenous fistulas and 34.1% vs 36.8% (P = .002) for prosthetic grafts. There was 5% decrease in primary patency (aHR, 0.95; 95% CI, 0.94-0.96; P < .001) for diabetics compared to nondiabetics who received autogenous fistulas. There was no difference in primary assisted and secondary patency for autogenous fistulas as well as primary, primary assisted, and secondary patency for prosthetic grafts in comparing diabetic to nondiabetic patients. There was also no significant difference in severe prosthetic graft infection between the groups (aHR, 0.99; 95% CI, 0.92-1.08; P = .90). There was a 19% increase in patient mortality for diabetic relative to nondiabetic autogenous fistula recipients (aHR, 1.19; 95% CI, 1.17-1.20; P < .001) and 12% increase for prosthetic graft recipients (aHR, 1.12; 95% CI, 1.10-1.15; P < .001). CONCLUSIONS: In this population-based cohort of hemodialysis patients, diabetes mellitus was associated with a decrease in patient survival, access maturation, and primary fistula patency. In contrast, there was no association between diabetes and prosthetic graft patency and severe prosthetic graft infection warranting excision.