Postsurgical Pain and Opioid Use in Older Adults: Effects of Mild Cognitive Impairment

Mild cognitive impairment (MCI) affects a substantial proportion of older adults undergoing major surgery and may alter pain processing, pain experience, and opioid use after surgery. This prospective observational cohort study will compare older adults with MCI and cognitively intact older adults undergoing major orthopedic and complex spine procedures. Participants will undergo preoperative assessment of cognitive function, quantitative sensory testing, heart rate variability, clinical pain, and biomarkers associated with Alzheimer's disease risk. Postoperative pain trajectories, opioid use, pain responsiveness, and cognitive outcomes will be evaluated for six months following surgery. The study aims to determine whether MCI is associated with differences in postoperative pain and opioid use outcomes and whether APOE4 status and plasma amyloid beta 42/40 ratio contribute to observed differences.

Inclusion Criteria: PATIENT PARTICIPANTS: * Aged 65 years or older * Ability to provide informed consent * English literacy sufficient to complete study measures * No daily opioid use in the prior 3 months * Residence within a 1-hour drive of Nashville * Deemed healthy enough for quantitative sensory testing (QST) procedures by surgical Co-Investigators * Undergoing elective surgical procedures including tier 2 or 3 procedures (e.g., posterior cervical fusion, thoracic/lumbar fusion \>= 3 levels) CAREGIVER PARTICIPANTS: * Age \>= 18 years at the time of consent * Identified as the patient's spouse/partner, adult family member, or other unpaid informal caregiver-and, for a patient scoring \