Association Between Different Patterns of Opioid and Benzodiazepine Use and Risks of Emergency Department Visits and Hospitalizations: A Retrospective Cohort Study.

: In 2016, the U.S. FDA warned against concurrent use of opioids and benzodiazepines (BZDs) due to risks of respiratory depression and death. However, limited data exist in Asian populations. : Using the Chang Gung Research Database in Taiwan, we conducted a retrospective cohort study of 418,549 patients prescribed opioids between 2008 and 2018. Patients were categorized into four groups based on BZD use: opioid-only (PureO), past BZD use (PastB), continuous BZD use (ContiB), and newly initiated BZD use (NewB). Multivariate logistic regression was used to evaluate all-cause emergency department (ED) visits and hospitalizations during the one year follow-up following one year of co-use. : Compared with PureO, co-use groups had significantly higher odds of hospitalization (ContiB: aOR = 1.74; PastB: 1.54; NewB: 1.48) and ED visits (ContiB: 2.09; PastB: 2.04; NewB: 1.51). Elevated risks were also observed among older adults, and patients with depression, stroke or transient ischemic attack, chronic obstructive pulmonary disease, chronic kidney disease, as well as those with higher Charlson Comorbidity Index scores. : Our findings support the need for cautious prescribing and individualized deprescribing strategies to reduce avoidable acute healthcare utilization.