title: A population-based matched cohort study examining the mortality and costs of patients with community-onset Clostridium difficile infection identified using emergency department visits and hospital admissions.
abstract: Few studies have evaluated the mortality or quantified the economic burden of community-onset Clostridium difficile infection (CDI). We estimated the attributable mortality and costs of community-onset CDI. We conducted a population-based matched cohort study. We identified incident subjects with community-onset CDI using health administrative data (emergency department visits and hospital admissions) in Ontario, Canada between January 1, 2003 and December 31, 2010. We propensity-score matched each infected subject to one uninfected subject and followed subjects in the cohort until December 31, 2011. We evaluated all-cause mortality and costs (unadjusted and adjusted for survival) from the healthcare payer perspective (2014 Canadian dollars). During our study period, we identified 7,950 infected subjects. The mean age was 63.5 years (standard deviation = 22.0), 62.7% were female, and 45.0% were very high users of the healthcare system. The relative risk for 30-day, 180-day, and 1-year mortality were 7.32 (95% confidence interval [CI], 5.94-9.02), 3.55 (95%CI, 3.17-3.97), and 2.59 (95%CI, 2.37-2.83), respectively. Mean attributable cumulative 30-day, 180-day, and 1-year costs (unadjusted for survival) were $7,434 (95%CI, $7,122-$7,762), $12,517 (95%CI, $11,687-$13,366), and $13,217 (95%CI, $12,062-$14,388). Mean attributable cumulative 1-, 2-, and 3-year costs (adjusted for survival) were $10,700 (95%CI, $9,811-$11,645), $13,312 (95%CI, $12,024-$14,682), and $15,812 (95%CI, $14,159-$17,571). Infected subjects had considerably higher risk of all-cause mortality and costs compared with uninfected subjects. This study provides insight on an understudied patient group. Our study findings will facilitate assessment of interventions to prevent community-onset CDI.
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada.|Toronto Health Economics and Technology Assessment Collaborative, Toronto, Canada.
authors.forename: Natasha
authors.initials: N
authors.lastname: Nanwa
authors.affiliation: Toronto Health Economics and Technology Assessment Collaborative, Toronto, Canada.|Public Health Ontario, Toronto, Canada.|Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Canada.|Institute for Clinical Evaluative Sciences, Toronto, Canada.
authors.forename: Beate
authors.initials: B
authors.lastname: Sander
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada.|Toronto Health Economics and Technology Assessment Collaborative, Toronto, Canada.|Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Canada.|Institute for Clinical Evaluative Sciences, Toronto, Canada.|University Health Network, Toronto, Canada.|Department of Medicine, University of Toronto, Toronto, Canada.
authors.forename: Murray
authors.initials: M
authors.lastname: Krahn
authors.affiliation: Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Canada.|Institute for Clinical Evaluative Sciences, Toronto, Canada.|Department of Medicine, University of Toronto, Toronto, Canada.|Sunnybrook Health Sciences Centre, Toronto, Canada.
authors.forename: Nick
authors.initials: N
authors.lastname: Daneman
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Canada.
authors.forename: Hong
authors.initials: H
authors.lastname: Lu
authors.affiliation: Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Canada.|Institute for Clinical Evaluative Sciences, Toronto, Canada.|Sunnybrook Health Sciences Centre, Toronto, Canada.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Austin
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Canada.|Mount Sinai Hospital, Toronto, Canada.|Division of General Surgery, Department of Surgery, University of Toronto, Toronto, Canada.
authors.forename: Anand
authors.initials: A
authors.lastname: Govindarajan
authors.affiliation: Public Health Ontario, Toronto, Canada.|Institute for Clinical Evaluative Sciences, Toronto, Canada.|Dalla Lana School of Public Health, University of Toronto, Toronto, Canada.
authors.forename: Laura C
authors.initials: LC
authors.lastname: Rosella
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada.|Institute for Clinical Evaluative Sciences, Toronto, Canada.
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Cadarette
authors.affiliation: Public Health Ontario, Toronto, Canada.|Institute for Clinical Evaluative Sciences, Toronto, Canada.|University Health Network, Toronto, Canada.|Dalla Lana School of Public Health, University of Toronto, Toronto, Canada.|Department of Family and Community Medicine, University of Toronto, Toronto, Canada.
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Kwong
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002170:Canada / Q000453:epidemiology; D002648:Child; D016360:Clostridioides difficile / Q000472:pathogenicity*; D003015:Clostridium Infections / Q000191:economics / Q000382:microbiology / Q000401:mortality* / Q000503:physiopathology; D015331:Cohort Studies; D003365:Costs and Cost Analysis / Q000191:economics; D003428:Cross Infection / Q000191:economics / Q000382:microbiology / Q000401:mortality* / Q000503:physiopathology; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D005260:Female; D006760:Hospitalization / Q000191:economics; D006801:Humans; D007902:Length of Stay / Q000191:economics; D008297:Male; D008875:Middle Aged