Table 1.
Clinical criteria for dementia and Alzheimer's disease
| Amnestic MCI3 | Dementia DSM-IV-TR1 | Alzheimer's disease NINCDS-ADRDA2 | Alzheimer's disease4* | |
|---|---|---|---|---|
| History | ||||
| Age | · · | · · | 40–90 years | · · |
| Progression | · · | Yes | Yes | Yes |
| Onset | · · | Gradual | Gradual | Gradual |
| Memory complaint | Yes | Yes | Yes | Core: early and significant >6 months |
| Activities of daily living | Normal | Impaired | Impaired | · · |
| Other CNS/general conditions | · · | Absent | Absent | Absent |
| Incoordination/gait disturbance | · · | · · | Absent | Absent |
| Early seizures | · · | · · | Absent | Absent |
| Examination | ||||
| Memory impairment | Core | Core | Core | Core: can be isolated |
| General cognitive function | Normal | One or more of: aphasia, apraxia, agnosia, disturbance in executive function | Deficits in at least two areas of cognition | Can be intact or deficits in areas of cognition other than memory |
| Delirium | · · | Absent | Absent | · · |
| General neurological function | · · | · · | Normal | Normal |
| Investigation | ||||
| MRI | · · | · · | · · | Medial temporal lobe atrophy |
| CSF | · · | · · | · · | Low amyloid, increased tau or phosphorylated tau |
| PET | · · | · · | · · | Bilateral temporoparietal hypometabolism on FDG-PET or abnormal PiB study |
| Genetics | · · | · · | · · | Proven FAD mutation in immediate family |
··=not addressed in that set of criteria. Early criteria for Alzheimer's disease had low specificity and could be used only to diagnose late in the course of the disease. Attempts to refine and accelerate diagnosis included describing a pre-Alzheimer's disease group: amnestic MCI. However, transition from MCI to Alzheimer's disease remained poorly defined. Recently published criteria amalgamate MCI and Alzheimer's disease and are the first to suggest use of biomarkers in diagnosis, reflecting changes in clinical practice.
MCI=mild cognitive impairment. DSM-IV-TR=Diagnostic and Statistical Manual of Mental Disorders, 4th edition text revision. NINCDS=National Institute of Neurological and Communicative Disorders and Stroke. ADRDA=Alzheimer's Disease and Related Disorders Association. PiB=Pittsburgh B compound. FDG=fluorodeoxyglucose. FAD=familial Alzheimer's disease. core=core features.
Probable Alzheimer's disease=core memory impairment plus one or more supportive investigations.