Objective: Our aim was to measure the prevalence of delirium, its clinical features, and outcomes in older patients referred to a memory clinic.

Methods: A retrospective cohort study of 109 older outpatients with delirium referred to a memory clinic with a home care service. Delirium was diagnosed using the confusion assessment method and dementia with the DSM-5 criteria. We collected information on cognitive and functional status, mortality, institutionalization, and hospitalization during 6 months following the delirium episode.

Results: Delirium prevalence was 3.6%, mostly of hyperactive type. Delirium worsened functional (ADL 2.95 ± 1.95 vs. 2.16 ± 1.84) and cognitive (MMSE 13.88 ± 8.96 vs.11.0 ± 9.49) status after 6 months compared to the baseline. The mortality rate was 29.4%, and 28.3% were admitted to a long-term facility after the episode of delirium. Of these patients, more than half were hospitalized during the follow-up. Of the 109 patients with delirium, 85 were managed at home and 24 were hospitalized. Patients who were hospitalized had more severe behavioral symptoms during the delirium episode. There was no difference in mortality and institutionalization according to the home or hospital management.

Conclusions: This retrospective cohort study adds novel information to the existing literature of an understudied setting and population. The study supports the need to further investigate the feasibility and efficacy of the hospital at home models for the prevention and management of delirium in a high-risk population.