Neurocognitive Disorders: Causes

00:01 There are other cognitive disorders that are really important to know about.

00:04 So let's start with Alzheimer's disease. The cause of this is low levels of acetylcholine.

00:10 The assessment is actually made post-mortem. When you are evaluating your actual patient what you are looking for is a progressive decline in their cognitive abilities.

00:23 However, the diagnosis cannot be definitively made until after they've passed.

00:28 At which point you'll be able to see on the autopsy enlarged ventricles and senile plaques, neurofibrillary tangles, and tau proteins which are the hallmarks for Alzheimer's disease.

00:41 Although the treatment is mostly physical and emotional support, there are some medications that can boost up the acetylcholine that can be useful such as Donepezil.

00:53 So these are things to consider in your management plan.

00:57 Vascular dementia is caused by the microvascular disease of the brain with small infarcts.

01:04 The assessment can be made with an MRI and while the treatment is largely supportive in nature and encouraging good nutrition and exercise, you can also work with your patient to mitigate the risk factors for further cerebrovascular accidents.

01:21 So for example, making sure their blood pressure and cholesterol are under very good control, possibly with medication managements.

01:29 Another cognitive disorder to consider is Pick's disease.

01:34 This is caused by atrophy of the frontotemporal lobes and it's often called Frontotemporal Lobes Syndrome.

01:42 So here you wanna make your assessment by looking at your patient for any acute personality changes. It may be helpful to talk with their family members who can give you some good information to tell you that this is an acute change and that the personality has in fact been affected.

02:01 Post-mortem there can be pick bodies found or intraneuronal inclusion bodies.

02:07 The treatment here is very supportive again. Sometimes cholinesterase inhibitors are useful as our low dose benzodiapines or antipsychotics for the patients who are extremely agitated and possibly suffering from some psychotic symptoms.

02:25 Huntington's disease is an autosomal dominant genetic disorder, something important to note for your exam, autosomal dominant.

02:34 The onset is around 30 years old up to 50 and it involves bizarre movements, basically choreiform type movements. Often, patients' will be depressed and also have some psychotic symptoms. The diagnosis can be confirmed through genetic testing and also MRI imaging can show cloudy atrophy.

02:56 The treatment here is largely supportive; patients tend to have early mortality.

03:02 One thing you can offer to family members is possible genetic testing to see if anybody's carrying that autosomal dominant gene.

03:11 Parkinson's disease is a prominent due to prominent neuronal loss of the substantia nigra, basically it leads to dopamine depletion and in your patient this will look like several things.

03:25 They may be bradykinetic or have cogwheel rigidity, pill rolling tremor, a masked facies, shuffling gait, and possibly dysarthria. The treatment is multiple.

03:37 A lot of medications can be helpful here including levodopa, carbidopa, amantidine, anticholinergic medications, dopamine agonists, and MAOI's.

03:49 Also, support and family education is extremely important.

03:54 Lewy body dementia is another type of dementia of unknown etiology.

03:59 It is characterized by the presence of Lewy bodies, which are abnormal aggregates containing alpha-synuclein, a presynaptic protein with unknown function.

04:09 Lewy bodies are found predominantly in the cortex and the substantia nigra of the patients with the disease.

04:16 The presentation mimics that of Parkinson’s dementia and includes cognitive decline, hallucinations - especially visual - and the motor features of Parkinson mentioned above.

04:27 The difference between Parkinson’s dementia is that in Lewy body dementia, signs and symptoms of dementia occurs before the Parkinsonian motor symptoms.

04:37 Multiple regimens have been used for the treatment of Lewy body dementia.

04:41 These include acetylcholinesterase inhibitors, such as rivastigmine, donepezil and galantamine; atypical antipsychotics, such as quetiapine, aripiprazole, clozapine; memantine and levodopa/carbidopa.

05:00 CJD is a prion disease and it's rapidly progressive and that's one of its key features.

05:09 So patients will often progress to dementia within 6-12 months, it is a very quick course. Another --