Objective: toxigenic Clostridium difficile is responsible for a spectrum of disease severity ranging from mild diarrhoea to fulminant colitis. This study attempts to determine the proportion of patients in each category of severity and evaluate the risk factors for a more prolonged and complicated course.
Design: prospective cohort study.
Setting: university teaching hospital.
Subjects: all patients with symptomatic C. difficile infection during 4 months of an outbreak (January-April 1995); n=73; median age 74 years (range 17-91).
Measurements: incidence of C. difficile-associated disease (CDAD); severity of disease; percentage of patients in each category of severity; risk factors for severe disease/prolonged symptoms (univariate and multivariable analyses).
Results: the incidence of CDAD was 0.93%. Of the cases identified, 18 (24.7%) had mild, self-limiting disease; 26 (35.6%) had moderately severe disease; 23 (31.5%) had prolonged symptoms and six (8.2%) had a complicated course. Although CDAD was more common in older patients (P < 0.001), increasing age was not a risk factor for severity. Significant risk factors for severe CDAD included low Barthel and abbreviated mental test scores (P < 0.01, P < 0.001 respectively) and recent endoscopy (P=0.03). Logistic regression analysis revealed the following independent predictors of severe CDAD: endoscopy [odds ratios (OR) 4.0, P=0.03] and cognitive impairment (OR 11.0, P < 0.01). A trend towards significance was noted for nasogastric tube insertion (OR 3.1, P=0.08). Complications of infection included dehydration, malnutrition and faecal incontinence (which was statistically significantly associated with more severe disease; P < 0.01).
Conclusion: risk factors for severity of CDAD include functional disability, cognitive impairment, and recent endoscopy. Anticipation of severe CDAD may limit morbidity and mortality.