Vascular Access and Risk of Bloodstream Infection Among Older Incident Hemodialysis Patients

RATIONALE & OBJECTIVE: Most new patients with end-stage renal disease (ESRD) initiate hemodialysis (HD) with a central venous catheter (CVC) and later transition to a permanent vascular access with lower infection risk. The benefit of early fistula use in preventing severe infections is incompletely understood. We examined patients’ first access and subsequent transitions between accesses during the first year of HD to estimate the risk for bloodstream infection (BSI) associated with incident and time-dependent use of HD access. STUDY DESIGN: A retrospective cohort study using enhanced 5% Medicare claims data. SETTING & PARTICIPANTS: New patients with ESRD initiating HD between January 1, 2011, and December 31, 2012, and having complete pre-ESRD Medicare fee-for-service coverage for 2 years. EXPOSURE: The incident and prevalent use of CVC, graft, or fistula as determined from monthly reports to the Centers for Medicare & Medicaid Services by HD providers. OUTCOME: Incident hospitalization with a primary/secondary diagnosis of BSI (International Classification of Diseases, Ninth Revision, Clinical Modification code 038.xx or 790.7). ANALYTICAL APPROACH: Extended survival analysis accounting for patient confounders. RESULTS: Of 2,352 study participants, 1,870 (79.5%), 77 (3.3%), and 405 (17.2%) initiated HD with a CVC, graft, and fistula, respectively. During the first year, the incident BSI hospitalization rates per 1,000 person-days were 1.3, 0.8, and 0.3 (P<0.001) in patients initiating with a CVC, graft, and fistula, respectively. After adjusting for confounders, incident fistula use was associated with 61% lower risk for BSI (HR, 0.39; 95% CI, 0.28-0.54; P<0.001) compared with incident CVC or graft use. The prevalent fistula or graft use was associated with lower risk for BSI compared with prevalent CVC use (HRs of 0.30 [95% CI, 0.22-0.42] and 0.47 [95% CI, 0.31-0.73], respectively). LIMITATIONS: Restricted to an elderly population; potential residual confounding. CONCLUSIONS: Incident fistula use was associated with lowest rates of BSI, but the majority of beneficiaries with pre-ESRD insurance initiated HD with a CVC. Strategies are needed to improve pre-ESRD fistula placement.