Epidemiology of vascular access in the Australian hemodialysis population.

BACKGROUND: A number of demographic and comorbid factors have been demonstrated to be associated with the placement of arteriovenous grafts (AVG) and central venous catheters (CVC) as opposed to native arteriovenous fistulas (AVF). However, no data are available regarding these factors in a hemodialysis population where AVF utilization is high.

METHODS: All adult patients on hemodialysis on September 30, 2001 in Australia were included in the study. Vascular access was recorded as AVF, AVG, or CVC. Patients were separated into incident (<150 days since first dialysis) and prevalent cohorts (> or =150 days). Multinomial logistic regression was used to assess factors associated with AVG and CVC use.

RESULTS: Of the 4968 patients who were studied, 877(17%) were classed as incident and the remainder prevalent. AVF were present in 61% versus 77%, AVG were present in 11% versus 19%, and CVC were present in 28% versus 4% in the incident and prevalent cohorts, respectively (all P < 0.001). After adjustment for confounding factors, age and female gender were associated with an increased frequency of AVG in both cohorts. In addition, type I diabetes mellitus was associated with increased frequency of AVG use in the incident cohort, whereas body mass index (BMI) > or =30 kg/m2 and peripheral vascular and cerebrovascular disease were significant in the prevalent group. For CVC, female gender, type I and II diabetes mellitus and late referral were associated with increased frequency in the incident cohort, while females, cigarette smoking, and peripheral vascular disease were predictive in the prevalent group. Significant variations in access type were also seen depending on geographic location.

CONCLUSION: Certain patient characteristics such as age and female gender, but not type II diabetes mellitus, remain significantly associated with AVG and catheter use despite the high prevalence of AVF use in Australia. However, the significant variation in risk by geographic location suggests more attention needs to be paid to physician practice patterns to increase AVF utilization rates.