Vascular access in haemodialysis patients: a modifiable risk factor for bacteraemia and death

Abstract

Background: Bacteraemia and the development of sepsis syndrome is second only to cardiovascular disease as the leading cause of death in patients on renal replacement therapy.

Aim: To determine the contributions of laboratory and clinical variables to the risk of bacteraemia and death in haemodialysis patients.

Design: Retrospective analysis.

Methods: We analysed all patients receiving haemodialysis in our renal unit at the beginning of January 2004 (n=263), recording clinical and laboratory variables for each patient at study entry. Bacteraemia and mortality were recorded for the subsequent 18-month period. Multivariate analysis using a Cox proportional hazards model was used to test for independent associations between variables and outcomes.

Results: During the study period, 45 patients (17.1%) developed bacteraemia and 65 (24.7%) died. Under multivariate analysis, use of dialysis catheters at study entry was a major factor in the development of bacteraemia and death with hazard ratios (HR) of 5.4 (p<0.001) and 2.8 (p=0.012), respectively, for tunnelled central venous catheters vs. arteriovenous fistulas (AVFs) and 3.1 (p=0.01) and 3.4 (p=0.001), respectively, for non-tunnelled central venous catheters vs. AVFs. Elevated CRP at study entry was independently associated with bacteraemia (HR 1.5 per unit log-CRP, p=0.006). Low serum albumin (HR 0.92, p=0.005) was independently associated with death.

Discussion: Use of synthetic vascular access catheters and heightened inflammatory state both have strong independent associations with subsequent bacteraemia and death. Bacteraemia surveillance strategies should be developed, with consideration of vascular access type and baseline inflammatory state as key components.