Clinical outcomes in older surgical patients with mild cognitive impairment

Area of Science:

• Geriatric Medicine
• Neuroscience
• Surgical Outcomes Research

Background:

• Older adults, a growing surgical population, often have underlying conditions like mild cognitive impairment (MCI).
• The interplay between MCI, delirium, and surgical outcomes requires further investigation.

Purpose of the Study:

• To estimate the relative risks of mild cognitive impairment (MCI) alone or with delirium on adverse surgical outcomes in older adults.
• To investigate the association between MCI and delirium incidence and severity.
• To assess the combined impact of MCI and delirium on postoperative complications and functional recovery.

Main Methods:

• Prospective, observational cohort study of 560 non-demented adults aged 70 years and older undergoing surgery.
• Estimation of relative risks (RRs) for adverse outcomes, including delirium, postoperative complications, length of stay, discharge disposition, and new cognitive impairments.
• Stratification of patients into groups: MCI alone, delirium alone, and concurrent MCI and delirium.

Main Results:

• Mild cognitive impairment (MCI) was associated with a nearly twofold increased risk of delirium (RR=1.9) and a 4.6-fold increased risk of severe delirium.
• Delirium alone, but not MCI alone, significantly increased the risk of major postoperative complications (RR=2.5) and prolonged hospital stay (RR=2.2).
• Patients with both MCI and delirium faced a 1.4-fold higher likelihood of discharge to post-acute facilities and a 3.6-fold increased risk of new cognitive impairments.

Conclusions:

• Mild cognitive impairment (MCI) is a significant risk factor for developing delirium and increases its severity in older surgical patients.
• Concurrent MCI and delirium synergistically elevate the risk of adverse outcomes, particularly new cognitive deficits and the need for post-acute care.
• These findings highlight the importance of identifying and managing MCI in older adults undergoing surgery to mitigate delirium risk and improve postoperative recovery.