To compare delirium characteristics and clinical outcomes between older adults with acute hip fractures and those hospitalized for non-surgical medical conditions.

Delirium, an acute fluctuating disturbance in cognition, affects over 7 million adults aged 65+ annually and is the most common surgical complication in this population. While its impact has been studied in specific cohorts, comparisons between different patient groups remain limited.

Hip fracture patients were matched to non-surgical medicine service patients by sex and age (±5 years). Baseline clinical characteristics and prospective assessments of delirium [Confusion Assessment Method (CAM)], physical function (Barthel Index, Lawton Instrumental Activities of Daily Living), cognition [Global Deterioration Scale (GDS)], Lewy Body Composite Risk Score (LBCRS), and Interpersonal Support Evaluation were collected. Differences were analyzed using non-parametric tests (Stata 17). Mixed-effects models assessed functional changes baseline and one month later.

After matching, there were no statistically significant differences in baseline demographics between the Hip Fracture (n=36) and Medicine (n=36) cohorts. The Medicine cohort had a higher median baseline Charlson Comorbidity Index (CCI) than the Hip Fracture cohort [6 (IQR 4–7.5) vs. 4.5 (IQR 3–6), p=0.032]. GDS scores were higher in the delirium group in both cohorts (p<0.001). Median LBCRS scores were elevated in delirious patients in both groups: hip fracture [2.5 (IQR 1.5–5) vs. 1 (0–3), p<0.001] and medicine [4 (IQR 3.5–4.5) vs. 0 (0–2), p<0.001]. Hip fracture patients with delirium experienced a 34-point decline in the Barthel Index at one month (p<0.0001), while no significant change was found between delirious and non-delirious Medicine patients. 

Delirium was associated with worse baseline cognition and higher LBCRS in both cohorts, highlighting a link to neurodegenerative processes. Despite higher comorbidities in medical patients, only hip fracture patients with delirium experienced significant functional decline at one-month. These findings highlight the need for tailored delirium management to reduce long-term impairment.