For the first time in 27 years, the US issued new diagnostic guidelines for Alzheimer’s disease. These recognize that Alzheimer’s occurs over a continuum of time, with the earliest part beginning when affected individuals still appear to be symptom free.
- Preclinical Alzheimer’s disease
- Mild Cognitive Impairment due to Alzheimer’s disease
- Alzheimer’s dementia
Preclinical, a newly recognized stage describes a time when a person appears healthy, but has amyloid deposits occurring in the brain, a noted hallmark of the disease. Researchers believe this occurs 10 years before the onset of symptoms and can be identified by sensitive scans.
The guidelines also officially recognize Mild Cognitive Impairment as part of the disease. It is important to know that Mild Cognitive Impairment, a diagnosis of early memory loss, does not always advance to Alzheimer’s.
Finally, the guidelines expand the criteria for dementia, including impairment in visual/special function, judgment and reasoning. The former guidelines only recognized declines in memory functions.
These stages will not be used in clinical diagnosis at this time, but in the research setting. The new guidelines will assist researchers in discovering interventions at the earliest stage of this disease, the preclinical one. It is believed the preventative measures and treatments would be most effective at that point in the disease course as compared to later in the illness.