Background: Previous studies suggest better outcomes among end-stage renal disease (ESRD) patients initiating hemodialysis (HD) with arteriovenous fistulas (AVFs) versus central venous catheters (CVCs). We sought to quantify the risk of septicemia or bacteremia among ESRD Medicare beneficiaries by vascular access type at HD initiation.
Methods:Using the enhanced 5% sample of Medicare beneficiaries, we identified and examined a retrospective cohort of incident ESRD beneficiaries in 2011-2012 from inpatient and outpatient claim files. The sample was limited to those who were 67 years and older, had full fee-for-service coverage two years before and one year after HD initiation, and were alive during the first year after HD initiation. The vascular access type used during the first 60 days of HD was identified by searching outpatient dialysis claims. The outcome was defined as hospitalization with septicemia (ICD-9-CM 038.xx) or bacteremia (790.7) during the first year after HD initiation. The association between access type and risk of acquiring septicemia or bacteremia was assessed by modeling the outcome as a function of first access type, demographics, healthcare setting of first HD, and total Medicare reimbursement across healthcare settings in the year prior to ESRD as a proxy for baseline health status and utilization.
Results: Our cohort consisted of 1771 beneficiaries who initiated HD in 2011-2012 and had their vascular access type reported within 60 days of HD initiation. Of these, 73%, 5%, and 22% started HD with CVCs, AV grafts, or AVFs, respectively. Median time to hospitalization was 63 days (IQR 0-161) with CVCs and 173 days (IQR 22-260) for AVFs. The adjusted risk of septicemia or bacteremia during follow-up was 71% lower (RR: 0.29; 95% CI: 0.20-0.43, p<0.0001) among beneficiaries starting HD with an AVF in comparison with those initiating with a CVC.
Conclusion: Among this fully covered Medicare population who survived the first year of ESRD, a high proportion of beneficiaries initiated hemodialysis with CVCs, and those patients exhibited a high risk of septicemia or bacteremia. Reducing delays in placing AVFs could prevent significant infection-related morbidity.