What risk factors contribute to C difficile diarrhea?
Acid suppression therapy is another risk
A systematic review that included a total of 2948 patients in 12 studies (cross-sectional, case-control, and cohort) evaluated acid suppression therapy and found an association between CDAD and use of histamine2-receptor antagonists (H2RAs) (OR=1.48; 95% CI, 1.06-2.06; NNH=45) and between CDAD and proton-pump inhibitors (PPIs) (OR=2.05; 95% CI, 1.47-2.85; NNH=21).9 Significant heterogeneity among the studies limited the interpretation of results, however.
The prospective cohort study of 101,796 patients also reported an increased risk of CDAD with H2RAs and PPIs.3 The risk of CDAD rose with progression from no acid suppression to H2RA use to daily PPI use to more frequent PPI use.3 Another cohort study of 1187 patients found an association between PPIs and CDAD (adjusted OR=2.1; 95% CI, 1.2-3.5).5
Using a score to gauge risk
Researchers studying a cohort of 54,226 patients developed a risk score using clinical characteristics associated with CDAD.10 The patients were older than 18 years, hospitalized longer than 48 hours, and had received broad spectrum antibiotics (intravenous glycopeptides, fluoroquinolones, penicillins, cephalosporins, or carbapenems). When the researchers tested their clinical risk index on a validation cohort of 13,002 patients, they found that increasing scores were significantly associated with increasing risk for C difficile colitis (OR=3.31; 95% CI, 2.61-4.91; area under the receiver operating characteristic curve=0.712).10
Recommendations
Clinical practice guidelines by the Society for Healthcare Epidemiology of America and the Infectious Diseases Society of America recommend minimizing the frequency and duration of antibiotics and the total number of antibiotics used.11 They also suggest private rooms, chlorine cleaning products, and contact precautions (gloves, hand hygiene, and disposable thermometers) to reduce risk.
The authors of the guidelines propose antimicrobial stewardship programs based on the local epidemiology of C difficile strains, including restricted use of cephalosporins and clindamycin, except for surgical prophylaxis.
