Abstract
OBJECTIVES: The objectives of this study were to identify variables associated with dementia and entry into aged residential care (ARC) and derive and validate a risk prediction model for dementia and entry into ARC. DESIGN: This was an observational study of prospectively collected Home Care International Residential Assessment Instrument (interRAI-HC) assessment data. SETTING AND PARTICIPANTS: Participants included all people age ≥65 years who had completed an interRAI-HC assessment between July 1, 2012 and June 30, 2018. Exclusion criteria included death or entry into ARC within 30 days of assessment and not living at home at the time of the assessment. MEASURES: InterRAI data from 94,202 older New Zealanders were evaluated for presence or absence of dementia. A multivariable competing-risks model for entry into ARC with death as the competing event was used to estimate subdistribution hazard ratios (SHR). RESULTS: In total, there were 18,672 (19.8%) persons with dementia (PWD). PWD were almost twice as likely to enter ARC as persons without dementia [42.8% vs 25.3%; difference 17.5% (95% confidence interval 16.7%‒18.2%)]. PWD at highest risk of entering ARC were those where there was a desire to live elsewhere (SHR 1.44), depression (indicated, SHR 1.15), poor cognitive performance (Cognitive Performance Scale minimal SHR 1.32 and severe plus SHR 1.91), and wandering (SHR 1.19). Factors associated with reduced risks of PWD entering ARC were living with a child or relative, alcohol consumption, and comorbidities. CONCLUSIONS AND IMPLICATIONS: A desire to live elsewhere, social isolation, independent activities of daily living, and depression were independently associated with entry into ARC. Supporting caregivers may improve outcomes for PWD that delay entry into ARC. Future revisions of the interRAI questionnaire could provide more insight on this matter.