Instead the new criteria "aim to define the clinical, biochemical, structural, and metabolic presence of Alzheimer's disease."
However, Dr. Dubois and colleagues pointed out that their proposed criteria are limited by the lack of specifics such as definitions and parameters needed to implement them in clinical practice. As a result, "validation studies of the proposed diagnostic criteria will clearly be needed," they wrote.
The key or cornerstone criterion proposed by Dr. Dubois and colleagues is episodic memory deficit that is isolated or in combined with other cognitive changes. Other features of episodic memory deficit include:
- Gradual and progressive change in memory function reported by patients or informants over more than six months.
- Objective evidence of significantly impaired episodic memory on testing.
Memory deficit should be combined with one or more of these supportive features:
- Presence of medial temporal lobe atrophy including volume loss of hippocampi, entorhinal cortex, and amygdala as determined by MRI.
- Low amyloid ß42 concentrations, increased total tau concentrations, or increased phospho-tau concentrations or combinations of these three.
- Reduced glucose metabolism in bilateral temporal parietal regions on functional PET, or other "well validated ligands, including those that foreseeably will emerge such as Pittsburgh compound B or FDDNP (fluoroethyl](methyl)amino]-2-naphthyl]ethylidene) malononitrile."
- Proven Alzheimer's disease autosomal dominant mutation within the immediate family.