For the purposes of sample description, we also obtained data on time-invariant variables, such as age, sex, and insurance status, which were compared among the subsamples with and without recent AUD claims. Because the case-control design allows for individuals to serve as their own control, we did not adjust for these time-invariant variables in our models. However, we included time-varying covariates corresponding to prescriptions for medications commonly found in alcohol and drug poisonings23; these included muscle relaxants, antispasmodics, opioids (not buprenorphine or methadone), antidepressants, mood stabilizers, antipsychotics, nonsteroidal anti-inflammatory drugs, and benzodiazepines (eTable 1 in the Supplement). The logic for including these was 2-fold. First, any interaction between these medications and OUD medications may be associated with the point estimates for the OUD medications. Second, use of these medications may serve as proxy variables for comorbidities that can be measured with greater frequency than diagnoses.
