In our study, several classes of medicines were analyzed at the chemical subgroup level (ATC fourth level), and exposure to high sedative load, use of benzodiazepines, monoamine oxidase type B inhibitors, antipsychotics (i.e., quetiapine), antiepileptic medicines (i.e., gabapentin, valproate), direct factor Xa inhibitor anticoagulant, and DPP‐4 inhibitors were identified as predictors of hospitalization for delirium or dementia. This evidence concerns the gene MAOB and delirium.