Moderate to high use of opioid analgesics are associated with an increased risk of Clostridium difficile infection.

INTRODUCTION: Risk factors for Clostridium difficile infection (CDI) include use of broad-spectrum antibiotics, advanced age and lack of an appropriate immune response. Whether antiperistaltics such as opioid analgesics also increase the risk of CDI is uncertain. The purpose of this preliminary study was to determine whether opioid analgesics increase the risk of developing CDI in hospitalized patients receiving broad-spectrum antibiotics.

METHODS: Hospitalized patients were assessed for incidence of CDI in relation to usage of opioid analgesics controlling for other known risk factors for CDI.

RESULTS: During the study period, a total of 32,775 patients were identified of whom 192 had CDI. In univariate analysis, incidence of CDI increased significantly with moderate or high usage of opioids (P < 0.0001). One hundred of 21,396 (0.47%) patients who did not receive opioids developed CDI. Twenty-two of 6955 patients (0.32%) with mild usage of opioids developed CDI [odds ratio (OR): 0.68; 95% confidence interval (CI): 0.43-1.1; P = 0.10]. Thirty of 33,203 (0.93%) with moderate usage developed CDI (OR: 2.0; 95% CI: 1.3-3.0; P = 0.0009). Forty of 1029 (3.7%) patients with high usage of opioids developed CDI (OR: 8.3; 95% CI: 5.7-12.1; P < 0.0001). Similar results were observed using a multivariate Cox proportional hazard model.

CONCLUSIONS: Moderate to high use of opioid analgesics were associated with an increased risk of CDI.