Video Transcription

Hi everyone. Welcome to another psych student video.

Today we're thinking about dementia. Dementia is a syndrome in which there are problems with memory, thinking, and problem-solving issues. There are many different causes and we will outline a few now here. Here we focus on the biological aspects of dementia, but it's really important to take a holistic approach and utilize the MDT team, and whilst there's lots of different types of dementia often, the causes are not very clear. Here we have listed Alzheimer's, hereditary problems, Lewy bodies, inflammatory problems and many more. 

 

So, Alzheimer's first of all then. This is a problem in which neural connections are lost due to plaques and Tangles which are a result of abnormal protein build up. This is a progressive problem and you get symptoms of memory impairment which worsen over time and the key part of diagnosing Alzheimer's is that it's quite an Insidious onset. It's not a sudden change and it affects thinking and problem solving, and language as well. But most often presents first as memory problems. This is caused by lots of different multifactorial issues and is related particularly to increasing age, family, history and sometimes cardiovascular disease is linked as well.

In the early and middle stages you can think about using acetylcholinesterase Inhibitors and these help to address the cholinergic deficit which is recognized in early Alzheimer's disease. This inhibits the enzyme which breaks down that acetylcholine, which is a type of neurotransmitter. In the later stages you might think more about memantine. This is an NMDA receptor antagonist and that modulates the effect of glutamate, which is an excitatory neurotransmitter, but sometimes also acts as a neurotoxin. 

The next type of dementia that will consider is vascular dementia. So, this can be either cortical or subcortical in origin. Cortical means it's affecting more of the lobes itself. So frontal lobe, parietal, temporal and occipital lobes. If it's subcortical that means it's below the cortex so that could affect the internal capsule, thalamus, basal ganglia, brainstem, cerebellum, those kind of structures. Cortical lesions therefore effect higher mental functions more often, so might present as aphasia  and memory and behavioural problems, and subcortical is more likely to affect quite specific movements. So maybe dysarthria, imbalance or tremor. Vascular symptoms present as a stepwise type of dementia. So, it's quite sudden drops that don't ever really return back to their baseline. And to manage this you look at really addressing vascular risk factors. So, diet, exercise, heart rate, blood pressure, cholesterol, those kind of things, and typical dementia drugs often aren't very helpful. 

Frontotemporal dementia sounds somewhat self-explanatory in the that it affects the frontal and temporal lobes. This is again, a progressive type of dementia and there's a degeneration in those areas, the frontal and temporal brain areas. This tends to be linked in with a younger age group and is more commonly diagnosed in the 45 to 60 years old group, but also occurs later on this is more likely to affect areas such as personality and behaviour as well as language, mental abilities such as organisation and planning and then later on tends to present more with those memory problems. There might also be physical problems such as swallowing and speech. This again is caused by an abnormal protein which develops in clumps damaging cells and builds up in these specific areas. Often, it's linked to genetics, but the causes aren't clear, and it sometimes it's called picks disease or frontotemporal lobar degeneration. Symptoms lead the treatment, so treatments are variable. It might be to do with treating depression, behavioural problems, movements or swallowing. And an MDT is vital here. 

Lewy Body dementia is where you get Lewy bodies, which build up in the brain. These are microscopic. It's not just one large Leary body as I've drawn out here, and it slowly again worsens over many years. It's quite rare and Lewy bodies are also found in Parkinson's disease. So, they're clumps of protein. Lewy Body dementia is much more likely to present with hallucinations, confusion or sleepiness, thinking problems and tremors and slow movements or Parkinsonism symptoms are quite predominant with sleep disturbances also really key. Treatment here is focused more on the symptoms again, medication might help with hallucinations, movement problems, and other therapies, things like the SALT (Speech and Language Team) team, might be really helpful, depending on the specific presentation. But often Lewy Body dementia results in a lot of functional disability and can really fluctuate. They're also very sensitive to neuroleptics so we have to be very careful with antipsychotics, but you might be able to use other dementia drugs or levodopa depending on the symptom profile.

There are some genetic links specifically within dementia, but they're still very rare. So, Huntington's is an inherited condition linked with memory, concentration and movement problems. If one parent has that Gene, there's a 50% chance that each child will have it. CJD (Creutzfeldt-Jakob disease) has four types, one is an inherited form, but this is very rare. CADASIL is a cerebral autosomal dominant arteriopathy with subcortical impulse and leukoencephalopathy. That's a rare inherited form of vascular dementia and often presents a series of mild strokes.

Finally, a few other presentations which might look like dementia. Some drugs might be linked to development but there's variable evidence here, and others might alter a cognitive function in a way that mimics dementia. There are inflammatory problems, things like vasculitis or HIV dementia, and then you've got PSP. So that's Progressive supranuclear palsy, and corticobasal degeneration, which are linked again to tau build up. In PSP you get more problems with eye control and in corticobasal degeneration a lot more problems with basal ganglia and balance problems. But again, both can present with a dementia type of illness and include memory loss.

Thank you for watching this video. I hope it's been helpful.