Relationship of Body Mass Index (BMI) and Age With Recurrent Clostridium difficile Infection

Abstract

Introduction: To assess whether low or high BMI or age greater than 65 years has an association with Clostridium difficile infection (CDI) recurrence. Methods: We conducted a retrospective chart review of laboratory-proven CDI based on ICD-9 code (008.45) between Dec 2010 and Dec 2013. All first-time cases were included and followed up for recurrence and refractory infections. Demographic, drug history, exposure, and comorbidity data was recorded. Data was analyzed using contingency table, chi2, and independent t-test using Statistical Package for the Social Sciences (SPSS). BMI cutoff of >35 kg/m2, >25 kg/m2, and <20 kg/m2 were used to assess a possible association with CDI in both ends of the spectrum. Results: Four hundred thirty-six patient charts were reviewed based on specified criteria. Of these, 35.8% were male, 29.6% white, and 67.2% black. Average age was 68.6+/-15.8 years (range: 20-100) and average BMI was 28.5+/-7.65 kg/m2 (range: 14-65). None of the patients had concomitant IBD; 40.4% were on PPI, 67% had recent use of antibiotics, and 49.4% had exposure to a healthcare facility. Average duration from discharge to presentation with CDI was 11.2+/-8 days. During admission 18.1% were admitted to ICU. Of those in ICU, average stay was 7.8+/-6.6 days (range: 1-29). Recurrent CDI was seen in 16% of patients and refractory infection in 2.1%. Among all patients, 18.8% had BMI >35 kg/m2, 66% >25 kg/m2, and 7.9% <20kg/m2. Among patients <65 years, 23.5% had BMI >35 kg/m2, 72.8% >25 kg/m2, and 7.4% <20 kg/m2. Overall our analysis showed no significant correlation between BMI >35 kg/m2, >25 kg/m2, or <20 kg/m2 with recurrence of CDI. In patients over 65 years, we found a protective effect of BMI >30 kg/m2 (p=0.004) with significant reduction in the recurrence of CDI. There was no significant difference in the rate of recurrence between patients older than 65 versus younger patients (p=0.559) or in the younger age group (65 years) for each of the 3 BMI cutoff values of >35 kg/m2 (p=0.126), >25 kg/m2 (p=0.461), or <20 kg/m2 (p=1.0). Recent use of antibiotic was not a risk factor for recurrent infection (p=0.974). Conclusion: BMI is not significantly associated with CDI recurrence when studied in aggregate across all age groups. However, there is a protective effect of higher BMI (>30 kg/m2) in the elderly (>65 years) with significantly lower rates of recurrence of CDI