Delirium Following Anticholinergic Use in Hospitalized Patients With Dementia

We sought to explore rates of delirium amongst hospitalized patients with dementia following orders for anticholinergic medications. We hypothesized that patients receiving anticholinergic medications would have higher rates of delirium than similar, unexposed patients. We performed a retrospective chart review of 23 031 hospitalized individuals with Alzheimer's disease, vascular dementia, or unspecified dementia from 2011-2018. Rates of delirium diagnosis and haloperidol orders following anticholinergic administration were compared to patients with dementia without anticholinergic orders. Significant differences in rates of delirium and orders for haloperidol were observed between exposed and unexposed groups, with delirium having a relative risk of 2.3 and orders for haloperidol having a relative risk of 10.4. The number needed to harm for anticholinergic exposure was 5.45 for delirium and 7.09 for haloperidol. The identified difference suggests that inpatient use of anticholinergic medications may increase the risk of delirium in hospitalized patients with dementia. Despite this risk, our review suggests that anticholinergic administration is common during hospital stays among patients with dementia. Anticholinergic use may be a modifiable risk factor for delirium prevention, which could improve inpatient management of patients with dementia.