These tests do not pick up diffuse metabolic changes associated with dementia in a person who shows no gross neurological problems (such as paralysis or weakness) on a neurological exam.The functional neuroimaging modalities of SPECT and PET are more useful in assessing long-standing cognitive dysfunction, since they have shown similar ability to diagnose dementia as a clinical exam and cognitive testing. The ability of SPECT to differentiate vascular dementia from Alzheimers disease, appears superior to differentiation by clinical exam.The value of PiB-PET imaging using Pittsburgh compound B (PiB) as a radiotracer has been established in predictive diagnosis, particularly Alzheimers disease. Prevention
Risk factors
An influential review increased the number of associated risk factors for dementia from nine to twelve in 2020. The three newly added risks are over-indulgence in alcohol, traumatic brain injury, and air pollution. The other nine risk factors are: lower levels of education, high blood pressure, hearing loss, smoking, obesity, depression, inactivity, diabetes, and low social contact. Many of these identified risk factors including, the lower level of education, smoking, physical inactivity and diabetes, are modifiable. Several of the group are known vascular risk factors that may be able to be reduced or eliminated. Managing these risk factors can reduce the risk of dementia in individuals in their late midlife or older age. A reduction in a number of these risk factors can give a positive outcome.
There are six main types of FTD. The first has major symptoms in personality and behavior. This is called behavioral variant FTD (bv-FTD) and is the most common. The hallmark feature of bv-FTD is impulsive behavior, and this can be detected in pre-dementia states. In bv-FTD, the person shows a change in personal hygiene, becomes rigid in their thinking, and rarely acknowledges problems; they are socially withdrawn, and often have a drastic increase in appetite. They may become socially inappropriate. For example, they may make inappropriate sexual comments, or may begin using pornography openly. One of the most common signs is apathy, or not caring about anything. Apathy, however, is a common symptom in many dementias.Two types of FTD feature aphasia (language problems) as the main symptom. One type is called semantic variant primary progressive aphasia (SV-PPA). The main feature of this is the loss of the meaning of words. It may begin with difficulty naming things. The person eventually may lose the meaning of objects as well. For example, a drawing of a bird, dog, and an airplane in someone with FTD may all appear almost the same. In a classic test for this, a patient is shown a picture of a pyramid and below it a picture of both a palm tree and a pine tree. The person is asked to say which one goes best with the pyramid. In SV-PPA the person cannot answer that question. The other type is called non-fluent agrammatic variant primary progressive aphasia (NFA-PPA).