BACKGROUND: The Centers for Disease Control and Prevention (CDC) estimates 29,000 people died within 30 days of infection with Clostridium difficile(CD) in 2011. The Colorado Department of Public Health and Environment (CDPHE) conducts active, population-based surveillance of CD among residents of the Denver metropolitan area. We determined mortality rates and causes of death among patients with CD in Colorado, and evaluated underlying conditions among patients who died within 30 days of incident CD infection.
METHODS: Incident CD cases from 2011-2015 were matched with death record data from the Colorado State Death Registry from 2011 to January 2016 to identify patients who died within 30 days of their most recent incident positive CD test and to identify up to 11 causes of death. An incident case was defined as any toxin or molecular assay positive test in a patient without a positive test in the previous 8 weeks. Death data was merged with data collected during retrospective medical record review on selected patients as part of population-based surveillance. Comparisons of the frequency of selected underlying conditions was conducted.
RESULTS: Of 16,537 patients with at least one incident CD-positive test from 2011-2015, 1059 (6.4%) died within 30 days. Ten percent of cases aged 65 years or older died within 30 days of their CD-positive test. Seventy-eight percent of all deaths that occurred within 30 days occurred among those 65 years and older. Deaths within 30 days decreased from 2011-2015 (7.5% to 5.7%). Enterocolitis due to CD was the most common underlying cause of death (13.7% of cases); among contributing causes of death and underlying causes of death, sepsis (unspecified organism) was most common (25.8% of cases). Chronic kidney disease, chronic liver disease, chronic pulmonary disease, congestive heart failure, diabetes and dementia were more prevalent in patients who died than those who did not.
CONCLUSIONS: Most deaths occurring following a positive CD test occurred in patients 65 years and older. CD infection and sepsis were the two most common causes of death and the prevalence of chronic underlying conditions was higher among patients that died within 30 days of a positive CD test. Further analysis is needed to explain the link, if any, to the underlying conditions and causes of death found in cases that died within 30 days of an incident CD test.