Preoperative Risk Factors for Subsyndromal Delirium in Older Adults Who Undergo Joint Replacement Surgery

Abstract

Background: Older adults with subsyndromal delirium have similar risks for adverse outcomes following joint replacement surgery as those who suffer from delirium.

Purpose: This study examined relationships among subsyndromal delirium and select preoperative risk factors in older adults following major orthopaedic surgery.

Methods: Delirium assessments of a sample of 62 adults 65 years of age or older were completed on postoperative Days 1, 2, and 3 following joint replacement surgery. Data were analyzed for relationships among delirium symptoms and the following preoperative risk factors: increased comorbidity burden, cognitive impairment, fall history, and preoperative fasting time.

Results: Postoperative subsyndromal delirium occurred in 68% of study participants. A recent fall history and a longer preoperative fasting time were associated with delirium symptoms (p ≤ .05).

Conclusions: Older adults with a recent history of falls within the past 6 months or a longer duration of preoperative fasting time may be at higher risk for delirium symptoms following joint replacement surgery.

Figure 1

Bar graph showing the percentage of participants with subsyndromal delirium with one delirium symptom (SSD-1), subsyndromal delirium with two delirium symptoms (SSD-2), and full delirium on postoperative day 1, 2, and 3 following joint replacement surgery.

Figure 2

Bar graph showing the frequency distribution of preoperative fasting time duration for older adults. Fasting times were calculated starting from the time of the participant's last known oral intake and ending at the surgery start time.