Educational scope notice: This is a study note for medical students, not medical advice, diagnosis, or treatment guidance. Clinical management should follow local protocols and current guidelines.
Mild cognitive impairment sits between normal aging and dementia: measurable cognitive decline with daily activities largely preserved. Amnestic presentations, where memory is the main deficit, most often reflect early Alzheimer pathology. Non-amnestic presentations affect other domains such as language or executive function.
Roughly 10–15% of people with mild cognitive impairment progress to dementia per year, so most amnestic cases progress over a decade. Progression is not inevitable: impairment can remain stable for years or revert to normal.
Amyloid PET looks for underlying Alzheimer pathology when prognosis matters. A positive result marks mild cognitive impairment due to Alzheimer disease, the group most likely to progress.
Stability over 6–12 months points back toward mild cognitive impairment or a reversible cause rather than dementia. Re-evaluation about every six months keeps the staging current.
Evidence anchors
- NICE. Dementia: assessment, management and support (NG97): https://www.nice.org.uk/guidance/ng97
- Alzheimer’s Association. Mild cognitive impairment: https://www.alz.org/alzheimers-dementia/what-is-dementia/related_conditions/mild-cognitive-impairment