PURPOSE: This study aimed to explore the perceptions of geriatricians and experienced geriatric trainees in Europe of the complex relationship between dementia, delirium and frailty, including their relative prevalence, overlaps and causality. METHODS: An online anonymous survey was administered across 30 European countries, via the mailing list of the European Geriatric Medicine Society (EuGMS), national member groups and the authors' professional networks. Questions were framed in the context of recently hospitalised 80-year-old patients. RESULTS: Within the 440 included surveys, respondents particularly over-estimated frailty prevalence in older hospitalised patients, with two-thirds choosing between 41 and 80% prevalence, when the literature suggests only 23-46%, but paradoxically underestimated the frequency of frailty in people with delirium (more than three quarters of responses across 21-80%
literature suggests 71-93%). Severe dementia and previous delirium were correctly considered the strongest risks for future inpatient delirium. However, many considered pre-frailty a moderate (44%) or even strong (19%) risk for future delirium, while a minority considered severe dementia a low risk. Respondents viewed delirium superimposed on dementia (DSD) as having the strongest influence on in-hospital mortality and discharge to residential care, dementia as having the strongest influence on future residential care admission, and frailty as the condition most strongly influencing future mortality. CONCLUSION: Geriatricians and experienced geriatric trainees across Europe gave varied responses to questions about delirium, dementia and frailty prevalence, co-occurrence and consequences. This indicates a need for the performance and wide dissemination of robust, prospective research examining all three conditions in older hospital cohorts. We suggest a merging of selective delirium-frailty and dementia-delirium interests to the dementia-delirium-frailty triumvirate.