Schizophrenia: Etiology and Pathophysiology (Nursing)

00:00 So, the pathophysiology of schizophrenia, we don't know exactly what causes schizophrenia.

00:09 We have a number of theories about it though. Genetics and neurodevelopment abnormalities is one theory of the development of schizophrenia. There's also something called the dopamine hypothesis. And this means that if there's increased dopamine, it impacts your motor and cognitive functions as well as the psychotic symptoms, those hallucinations and delusions we just spoke about. Also, there is a serotonin excess and this serotonin excess in the brain is responsible for some of those negative symptoms; the anhedonia, the immotivation, the apathy. There is also the NMDA inhibitory neurotransmitter. Now, when you're thinking about all of these neurotransmitters, it's really important to remember that the neurotransmitter is the messenger. It is the messenger in between the different parts of the brain. It's what allows the different thoughts to connect and it's also what allows your brain to function well. And when there is a problem with all of these neurotransmitters like dopamine, serotonin, NMDA, it's important to understand that the brain and the thoughts can't function naturally and normally. Also, we look at stress being a problem because it causes a dysfunction in the biochemical response system of the individual. Well, we're also thinking about the other etiologies or where schizophrenia might be coming from, we want to think about genetic abnormalities, perhaps it's something during the time that the genes are just developing. It also can be early environments, highly stressful environments. Remember we spoke about ACES, adverse childhood experiences. We are looking in to the theory that this kind of very early environments that are very stressful might also play a role in the etiology. The neurobiology of schizophrenia, thinking about these neurotransmitters and their development. Also, viral and immune disorders, toxoplasmosis for example also called a cat scratch fever. Mothers who are exposed to toxoplasmosis during pregnancy also might have an etiology with the development of the fetus and schizophrenia. Finally, stress. Stress is an exacerbating factor in schizophrenia.

03:04 It is an exacerbating factor in almost all mental illnesses. So, what are we talking about when we say comorbidities? What do we see alongside of the person who has been diagnosed with having a schizophrenia disorder? Very frequently, a comorbid disorder with schizophrenia disorder is substance abuse disorders. And that includes alcohol misuse that includes opiums, cocaine, nicotine. These are substance use disorders that very frequently go hand in hand in schizophrenia. Also, depression, a person might also have depression at the same time as having schizophrenia. Also anxiety disorders, a person who has schizophrenia might also be suffering from generalized anxiety disorder. What's important to keep in mind is that a person who has diabetes can also have heart disease.

04:17 A person who has lung disease, can also have impaired mobility. Comorbidities in a body that is filling one diagnosis is not unusual. Comorbidities that are also too psychiatric diagnosis are not unusual. So, let's think about the prevalence. We have 40-60% of persons who have a schizophrenia disorder that also have a substance use disorder and it usually is negative outcomes if they have these two, because if you have a substance use disorder you're at higher risk for HIV, for example. If you have a substance use disorder, you may overdose whether it is intentional or unintentional and therefore you might have suicide. If a person is using needles and sharing needles, there's also an increased risk for hepatitis. 20-40% of those persons with schizophrenia also have depressive disorders. It is coming as part and parcel as you are beginning to have this thought disorder. As you are losing your touch with reality, you may start feeling hopeless and up to 65% of the people who are diagnosed with schizophrenia have an anxiety disorder. And when we consider all of these different disorders and we consider what a thought disorder might do as you are progressing in your life, if you are a teenager, if you are a young adult, if you're somebody who is in their 20s and 30s and these symptoms start occurring, well, you might have already had some depression in the past or some anxiety. And if you try to self-medicate with substances, you are just adding fuel to the fire.