The impact of angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers in patients with Clostridium difficile infection.

There is increasing frequency and severity of disease due to Clostridium difficile infection (CDI). In addition, failure of initial antibiotic therapy is increasing. Angiotensin-converting enzyme inhibitors (ACEI) and angiotensin-receptor blockers (ARBs) may have local and systemic anti-inflammatory properties to reduce severity of disease in CDI. We performed a retrospective study of 306 patients with CDI over 23 months at a single center in Detroit, Michigan. Patient outcomes (death, death due to CDAD and relapse rates) were compared based on the use of ACEI or ARB during an episode of CDI. A total of 116 (37.9%) patients received an ACEI/ARB and 190 (62.1%) did not. The groups were similar except ACEI/ARB patients were older (71.9 vs. 64.3, P<0.0005) and had a higher frequency of congestive heart failure (50.9% vs. 30.2%, P<0.0005) and chronic obstructive pulmonary diseases (44.8% vs. 30.2%, P<0.010). ACEI/ARB patients had lower overall mortality rates (9.5% vs. 23.3%, P<0.002) as well as mortality due to CDI (2.6% vs. 8.6%, P<0.036). The rate of CDI relapse was not significantly different between the groups (5.2% in ACEI/ARB vs. 10.0%, P=0.135). Logistic regression analysis demonstrated that ACEI/ARB use was associated with lower overall mortality rate (OR 0.26; 95% CI, 0.12-0.55) and mortality due to CDI (OR 0.29; 95% CI, 0.08-1.02). Our findings suggest that ACEI/ARBs may have a role as an adjuvant therapy to antibiotics in patients with CDI. Prospective studies are needed to confirm these results.