Objective: More people are living beyond their 90s, yet this group has not been much studied. This study aimed to describe a sample of non-agenarians and centerians attending an old age psychiatry service with a focus on pharmacotherapy.

Methods: Retrospective, cross-sectional survey of patients aged >90 in contact with the Department of Old Age Psychiatry in a university hospital over a 1-year period. Results were compared with the Beers, the Canadian and Screening Tool of Older Persons’ potentially inappropriate Prescriptions (STOPP) criteria.

Results: A total of 65 nonagenarians or centerians were identified (mean age 93, 82% female). The majority (65%) resided in a nursing home; dementia was the most common diagnosis (77%), followed by depression (29%). The most commonly prescribed psychotropics were antidepressants (58%), followed by antipsychotics (45%), hypnotics (42%), anti-dementia agents (31%) and anxiolytics (26%). Overall, patients were on a mean of 2.1 (S.D. 1.3, range 0–5) psychotropics and 4.99 (S.D. 2.7, range 0–11) non-psychotropics. Mean Mini Mental State Examination (MMSE) score was 15 (S.D. 8.1). Increasing anticholinergic burden was negatively associated with MMSE scores (B = −1.72, p = 0.013). Residing in a nursing home was associated with a higher rate of antidepressant [OR 5.71 (95% CI 1.9–17.4)], anxiolytic [OR 13.5 (95% CI 1.7–110.4)] and antipsychotic [OR 3.4 (95% CI 1.1–10.4)] use. Potentially inappropriate prescribing included long-term benzodiazepine use (26%) and long-term antipsychotic use (25%).

Conclusions: Our sample had a high psychiatric morbidity burden with high levels of psychotropic use. Ongoing review and audit of psychotropic use in elderly patients can identify potentially inappropriate prescribing in a group vulnerable to high levels of polypharmacy and extended psychotropic use.