The Impact of Age and Number of Previous Anesthesia on the Development of Mild Cognitive Decline (MCI) in Patients Enrolled for Cardiac Surgery

Mild Cognitive Impairment (MCI) is a common neuropsychiatric term encompassing a greater-than-expected cognitive decline for patient's age and schooling and no more than mild functional impairment that is insufficient to meet the threshold for a diagnosis of dementia (DSM-V: "mild neurocognitive disorder") thus forming part of a declining cognitive trajectory.

For the diagnosis of MCI, the core clinical criteria are: concern about a change in cognition, impairment in one or more cognitive domains, preservation of independence in functional abilities and no presence of dementia.

The Montreal Cognitive Assessment (MoCA), a test that was developed specifically for detection of MCI, has a sensitivity of 80 to 100% and specificity of 50 to 76% using a cut-off point of 25 to make diagnosis, and it has been suggested that it is better than Mini Mental Status Evaluation (MMSE) in accurately differentiating individuals with MCI from those with normal cognition.

Various risk factors have been proposed for MCI, in particular the role of multiple biological, behavioural, social and environmental factors have been investigated.

Of them, increasing in age, lower educational level, sleep-disordered breathing and vascular risk factors (e.g. diabetes and hypertension) seem to be the most important.