Risk of catheter-related bloodstream infection in elderly patients on hemodialysis

Abstract

Background and objectives: Elderly patients require tunneled central vein dialysis catheters more often than younger patients. Little is known about the risk of catheter-related bloodstream infection in this population.

Design, setting, participants, & measurements: This study identified 464 patients on hemodialysis with tunneled central vein dialysis catheters between 2005 and 2007 and excluded patients who accrued <21 catheter-days during this period. Outpatient and inpatient catheter-related bloodstream infection data were collected. A Cox proportional hazards regression analysis adjusting for sex, ancestry, comorbidites, dialysis vintage, dialysis unit, immunosuppression, initial catheter site, and first antimicrobial catheter lock solution was performed for risk of catheter-related bloodstream infection between nonelderly (18-74 years) and elderly (≥ 75 years) patients.

Results: In total, 374 nonelderly and 90 elderly patients with mean (SD) ages of 54.8 (12.3) and 81.3 (4.9) years and dialysis vintages of 1.8 (3.3) and 1.5 (2.9) years (P=0.47), respectively, were identified. Mean at-risk catheter-days were 272 (243) in nonelderly and 318 (240) in elderly patients. Between age groups, there were no significant differences in initial catheter site, type of catheter lock solution, or microbiology results. A total of 208 catheter-related bloodstream infection events occurred (190 events in nonelderly and 18 events in elderly patients), with a catheter-related bloodstream infection incidence per 1000 catheter-days of 1.97 (4.6) in nonelderly and 0.55 (1.6) in elderly patients (P<0.001). Relative to nonelderly patients, the hazard ratio for catheter-related bloodstream infection in the elderly was 0.33 (95% confidence interval, 0.20 to 0.55; P<0.001) after multivariate analysis.

Conclusion: Elderly patients on hemodialysis using tunneled central vein dialysis catheters are at lower risk of catheter-related bloodstream infection than their younger counterparts. For some elderly patients, tunneled central vein dialysis catheters may represent a suitable dialysis access option in the setting of nonmaturing arteriovenous fistulae or poorly functioning synthetic grafts.

Figure 1.

Hazard ratios for catheter-related bloodstream infections across the range of ages. Hazard ratio (HRs) with 95% confidence intervals (95% CIs) by age group relative to elderly subjects≥75 years are shown. A dashed reference line for lack of significant association is drawn at HR, 1. Age group: 18–35 years: HR, 4.5; 95% CI, 2.0 to 7.0; P<0.001; 36–45 years: HR, 3.1; 95% CI, 1.3 to 4.9; P<0.001; 46–55 years: HR, 2.8; 95% CI, 1.2 to 4.4; P<0.001; 56–65 years: HR, 3.7; 95% CI, 1.6 to 5.8; P<0.001; 66–74 years: HR, 1.7; 95% CI, 0.9 to 2.5; P=0.07.