A Study of Central Line-Associated Bloodstream Infections in ICU and Non-ICU Settings

Background: Central line-associated bloodstream infections (CLABSI) account for 14% of the often preventable HAIs. Traditionally, surveillance targeting intensive care units (ICU) report an estimated 250,000 episodes of CLABSI associated with 30,000 death, and accounting for $296 million in healthcare expenses, annually. Little has been reported about CLABSI rates in the non-ICU setting. Objective: Describe the rate, risk factors, mortality, and cost of CLABSI in ICU and non-ICU settings. Methods: Data for this analysis was obtained from Premier Inc for January 1, 2004 to December 31, 2008. CLABSI was defined as a discharge with a billing code or ICD9-CM procedure code for a central line procedure (38.92, 38.93, and 38.95) and an ICD9-CM diagnosis code for a BSI (16 codes). CLABSI rates were reported per 1,000 catheter days. A hierarchical logistic regression model was used to estimate the risk of CLABSI and mortality in ICU and non-ICU settings. A log-linear model was estimated to determine if the presence of CLABSI had a positive significant effect on the cost of hospitalization. Each hypothesis was specified as non-directional and tested using a 95% confidence interval. Results: The final study population consisted of 1,402,869 patient discharges from 479 hospitals. CLABSIs occurred in 80,687 (5.75%) discharges resulting in 5.74 CLABSIs per 1,000 catheter days. Fourty-two percent (33,586) of CLABSIs occurred in the ICU resulting in 6.70 CLABSIs per 1,000 catheter days. Fifty-eight percent (47,101) of CLABSIs occurred in the non-ICU setting resulting in 5.20 CLABSIs per 1,000 catheter days. Age (OR 1.008; CI 1.007-1.009), male (OR 1.037; CI 1.015-1.059), length of catheterization (OR 1.026; CI 1.024-1.029), number of procedures (OR 1.095; CI 1.087-1.103) and co-morbidities measured by the Deyo Modified Charlson Co-morbidity index (OR 1.074; CI 1.06-1.081) all significantly increased the risk of CLABSI. Compared to 2004 the risk of CLABSI decreased in 2006 (OR 0.902; CI 0.857-0.949), 2007 (OR 0.879; CI 0.830-0.930), and 2008 (OR 0.852; CI 0.804-0.902). Among hospitalized patients with a catheter, CLABSI was associated with a more than two-fold increased risk of mortality (OR 2.003; CI 1.932-2.077). However, the risk of patients with a catheter dying decreased significantly each year in comparison to 2004. Average cost of a CLABSI-related hospitalization was $59,161 in 2008 US dollars. Presence of CLABSI had a positive significant effect on cost (0.217, p<0.0001). In comparison to 2004, cost decreased significantly in each of the subsequent years. Conclusions: More than half of all CLABSIs occur in the non-ICU setting. However, the rates per 1,000 catheter days are slightly higher in the ICU compared to the non-ICU. Rates of CLABSI are decreasing, as are hospital mortality and the cost of care associated with these preventable events.