Delirium is a risk factor for institutionalization and functional decline in older hip fracture patients

Objectives: The risk of institutionalization and functional decline is substantial after a hip fracture. However, previous research has not established the extent to which delirium plays a contributory role.

Methods: Using a prospective design, we studied 207 hip fracture patients aged 65 and older, home-dwelling before the fracture. Patients were screened daily for delirium using the Confusion Assessment Method. Proxy information on pre-fracture cognitive function and function in activities of daily living (ADL) was obtained using the Informant Questionnaire on Cognitive Decline in the Elderly, 16-item version, and the Barthel ADL Index. After 6months, the patients' functions in ADL measured by the Barthel ADL Index and place of living were registered.

Results: Delirium was present in 80 patients (39%) during the hospital stay. After 6months, 33 (16%) were institutionalized. Delirium and lower Barthel ADL Index score were the main risk factors for institutionalization with an adjusted odds ratio (AOR) of 5.50 (95% CI=1.77-17.11) and 0.54 (95% CI=0.40-0.74) respectively. In patients able to return to their private home, the independent risk factors for functional decline were higher age (B=0.053, 95% CI=0.003-0.102) and delirium (B=0.768, 95% CI=0.039-1.497).

Conclusions: At 6month follow-up, delirium constitutes an independent risk factor for institutionalization and functional decline in hip fracture patients living at home prior to the fracture.