Why is differential diagnosis of dementia challenging?
As covered in the Differential Diagnosis Lecture, and considered in the VaD Lecture, deciding if someone has some form of dementia (aka Major Neurocognitive Disorder) can be challenging in some cases, but even when that decision is quite clear, there is are further challenges about which kind of dementia an individual may have. As different kinds of dementia and their subtypes have very different profiles, it is important provide as precise and accurate a diagnosis as possible. Differential diagnosis refers to the process of deciding which kind of dementia an individual has from a range of alternatives. This is not a simple task because the correspondence between each level of explanation and subtypes (i.e., clinicopathological correlations) is not perfect.
For your essay, you obviously have limited space, you could consider empirical work relating to some of the following issues:
– Overlap between dementia subtypes in terms of their symptomatology
– Overlap between dementia subtypes in terms of the nature of neural damage
– Accuracy of the mapping between dementia subtype diagnosis and pathology
– Accuracy of the mapping between dementia subtype and genes
– Practical issues of awareness of subtypes and access to expertise for diagnosis
You do not need to cover all of these levels, and it is fine to be selective in your focus, but you need to flag that you will be doing this and provide a reason why in your essay. Similarly, there are of course many dementia subtypes that could be considered, and you do not need to consider all of them. One strategy is to perhaps take two or three subtypes and consider differential diagnostic accuracy between these throughout your essay. Another strategy might be to take sets of subtypes for different kinds of evidence that best illustrate the challenges in terms of accuracy. The choice as to which strategy to adopt is up to you and should be based in the analysis of the literature you find via searching (preferably via library databases like SCOPUS), and your own interests.