Dementia, as readers of this blog are no doubt well aware, is a health problem which particularly (but not exclusively) strikes the older adult population and, because of the “greying of America” that’s been going on, will only increase in prevalence over the coming years. Increasing age, of course, is a major risk factor for developing dementia.
Let’s define dementia first. Probably one of the most influential definitions of dementia is in the American Psychiatric Associations’ Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text-Revision (DSM-IV-TR for short), which basically says that to have a dementia of any sort, you must have
1) the development of multiple cognitive deficits manifested by both:
a) memory impairment (impaired ability to learn new information or to recall previously learned information); and
b) one (or more) of the following cognitive disturbances:
i) aphasia (language disturbance),
ii) apraxia (impaired ability to carry out motor activities despite intact motor function),
iii) agnosia (failure to recognize or identify objects despite intact sensory function), or
iv) disturbance in executive functioning (i.e., planning, organizing, sequencing, abstracting).
2) The above cognitive deficits need to produce “significant impairment in social or occupational functioning and represent a significant decline from a previous level of functioning.” Which means that if the person has cognitive deficits as specified above (say, identifiable via neuropsychological testing) but seems to function well, miraculously, in their daily life, then they don’t have dementia and may instead have something milder, say, mild cognitive impairment.
Complexifying things further, the DSM-IV-TR is currently poised to be updated to DSM-V (just when we got comfortable with the mental disorders we already had!), and we already know that the diagnostic criteria for what is considered dementia will likely shift anyways. But we’ll go with the DSM-IV-TR definition, because it’s still current and it works and makes sense for me as a practitioner (except perhaps for the requirement that memory dysfunction always be central to having a dementia).
So what about Alzheimer’s Disease? One of the common misconceptions I run into when talking to people about what I do as a geropsychologist (aside from people constantly mistaking me for a psychiatrist) is that “dementia” and “Alzheimer’s” are synonymous. Alzheimer’s Disease, of course, is only one of many, many difference dementia subtypes – dementia is an umbrella category of which Alzheimer’s disease falls under. There are other dementias, such as vascular (stroke) dementia, Lewy Body dementia (which I plan on posting about in the near future), dementia due to alcohol, Frontotemporal dementia, and many, many others.
Dementia is what I do for a living, basically. Look for more posts about the subject down the line.