A new meta-analysis examined four studies covering almost 120,000 patients and found a higher rate of C. diff among people taking opioids. About 31% of patients on opioids developed C. diff, compared with 17% of patients who were not using opioids. The team notes that people taking certain antibiotics or those with weakened immune systems are already at higher risk; opioid use could be an additional factor.
Past research cited in the paper suggests two possible mechanisms. Opioids can suppress the immune response that fights infections and they can disrupt the balance of healthy gut bacteria. Healthy gut bacteria help defend against pathogens such as C. diff.
Coauthor Lorenzo Villa-Zapata said evidence is mixed, and lead author Pooja Gokhale noted that opioids can "mess with the gut microbiome" and increase susceptibility. The researchers recommend that physicians weigh benefits and side effects and make case-by-case decisions.
Difficult words
- meta-analysis — Study that combines results from several studies
- opioid — Drug used to reduce severe painopioids
- antibiotic — Medicine that kills or stops bacteria growthantibiotics
- immune system — Body's organs and cells that fight infectionimmune systems
- microbiome — All the microorganisms living in one body area
- susceptibility — How likely someone is to get an illness
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