Welcome to the Oxford University Psychiatry podcast series, you're here with Daniel Maun and Charlotte Allen, both advanced trainees in Oxford Deanery. Today we're going to be talking about schizophrenia. This is a very important condition in psychiatry and is one that sometimes difficult to understand, especially for students first starting out in the discipline. So, Daniel, maybe we could begin by asking what the word schizophrenia actually means.
Schizophrenia actually means split mind, but importantly, it doesn't mean split personality. Often people equate schizophrenia diagnosis with a Jekyll and Hyde type of presentation. But this is actually quite far off from the truth. The term schizophrenia was first coined by Bleuler in 1988 and was intended to describe the separation or splitting of the different functions of the mind between personality, thinking, memory and perception.
It sounds then that's like schizophrenia affects a huge number of different cognitive and mental functions, but can you say exactly what it is? Yes, you are right. It does affect lots of different cognitive functions. And I think the most important thing to realise is it is a serious mental illness. It's characterised by psychotic symptoms, including hallucinations, delusions and thought disorder. Schizophrenia affects a person's ability to distinguish between what's real and what's not real.
As a result, they can begin to think, feel and behave in ways that are out of character from for them. And they can begin to develop beliefs that are not real. They can begin to experience things which aren't real, and their thoughts can become disjointed and confused at times. And as a result of all these different things going on, they can often become distressed or fearful, sometimes agitated. How common is it? Well, there's an overall lifetime risk of about one percent.
The onset is characteristically between 15 and 45 years. Unlike men. Interestingly, women show a bimodal peak of incidence across the ages, with 10 percent of women having their first onset in middle age. There is a slight male preponderance, which is more pronounced in more severe forms as well. I think you've given us a good idea about what schizophrenia is overall. Can you tell us a little bit about the symptoms of schizophrenia?
Yes, the symptoms can be grouped into two main categories positive and negative symptoms. Positive symptoms are called positive because they don't appear normal in the general population. But they are present in those with schizophrenia, these include hallucinations and delusions, negative symptoms are deficits of normal function, such as reduced emotional responses or confused thought processes. Other negative symptoms include social withdrawal or poor motivation as well.
And can you say anything about what causes schizophrenia? Well, the causes are multifactorial and include genetics, life stressors, obstetric complications, drug and alcohol use. There are many different causes and it can be quite hard in any given individual to really pinpoint what the causes might be. You mentioned genetics that if there is schizophrenia, a heritable condition, it is a heritable condition.
But due to the genetic contribution to the condition, it's more accurate, actually, to say that a person inherits the vulnerability of developing the condition rather than the condition itself. In other words, schizophrenia might develop due to the cumulative effects of several gene polymorphisms, although it should be noted that those with schizophrenia are genetically heterogeneous group and it's likely that both genetic and non genetic forms exist. OK, you also mentioned drug and alcohol use.
Can you tell me a bit more about the contribution of substance misuse to schizophrenia? Well, it's widely accepted that psychoactive drugs such as amphetamines, cannabis, LSD and ketamine can provoke psychotic symptoms in both those with schizophrenia and actually healthy controls. There was a well-known, large, large cohort study in Sweden of actually of them of their military conscripts.
And they found that cannabis intake at 18 years of age was associated with an increased risk of late psychosis with a relative risk of 2.5. And interestingly, this list increased six fold risk for heavy users. So that study is quite well known because it shows a dose related effect and is accepted. The cannabis clearly does increase the risk, but its impact on the development of schizophrenia. Some say now is not as great as previously feared.
OK, so there's some evidence that it might increase the risk, but it's not necessarily going to lead to schizophrenia. That's right. Are there any other risk factors that might contribute to the development of schizophrenia? In theory, any environmental stressor or significant life event can trigger the development of schizophrenia. Factors such as social adversity, social isolation, migrant status, and, in fact, urban life as well.
There are many different factors that are associated with an increased risk. In the past, schizophrenia was known as a functional illness because it was thought that there were no actual changes in the brain. But I know that now we've got a lot more advanced tools to investigate brain structure, things like neuroimaging. And I just wondered if you could say anything more about the structure of brain abnormalities that are found in schizophrenia.
Yes, there have been many studies that use structural imaging techniques such as CTE or MRI scanning that are so consistent abnormalities in people with schizophrenia, including decreased brain volume, particularly in the frontal and temporal lobes, thalamus and white matter tracks in large third natural ventricles is a common finding. Smaller medial temporal lobes, decreased cortical grey matter and reduced cerebral asymmetry, a rather common findings.
It sounds like there are quite a lot of macro structural changes. Then how about on the micro structural level? Is there any evidence to suggest that there's anything going wrong in terms of neurochemicals in the brain? Yes, the main neurochemical implemented in schizophrenia is don't. For me, this was originally actually due to the accidental finding that Fener thiazide drugs which blocked dopamine function,
reduce psychotic symptoms. Another factor which supports this don't mean hypothesis is that amphetamines, which trigger the release of data mean can induce psychotic symptoms and help individuals and those in schizophrenia. As I mentioned earlier, in addition to this, all antipsychotic drugs don't mean receptor antagonists.
And or at least interact with the domain in a modulated fashion, as some of the modern drugs do, and there's been a good study showing that affinity with the D2 receptor correlates with clinical potency of medication. It sounds like dopamine is then a very important chemical in schizophrenia.
Are there any others that are also important? Yes. More recently, glutamate has been found to be involved, in particular the NMDA glutamate receptor antagonist of this NMDA receptor, such as ketamine or fennel. Claudine or PCP, as it's more commonly known, can induce a schizophrenia like psychosis. How would you actually go about diagnosing schizophrenia? Well, I think it's best that we focus on the subtype of paranoid schizophrenia here.
There are other subtypes, including apophatic and catatonic, but these are much less common. OK, so we'll focus on paranoid schizophrenia for today. OK, so if we use the World Health Organisation's ICD 10 diagnostic criteria, then you would need specific symptoms for at least one month. This is opposed to the American DSM system where you would need symptoms for at least six months for a diagnosis.
So taking the World Health Organisation, the ICD 10 criteria, which is what we use here in the UK, you need either one primary symptom or two secondary symptoms for at least one month. And what are the primary symptoms? Primary symptoms include Sawako thought insertion for withdrawal and thought broadcast. Can you explain what these are? Well, first of all, dealing with thought echo, this is the perception that your thoughts are being heard out loud.
So that's actually a hallucination. Moving on to thought insertion, withdrawal and broadcast for insertion is the belief that somebody else or something else is inserting thoughts in your head. Thought withdrawal is the belief that somebody or something is taking thoughts out of your head and thought broadcast is the belief that your thoughts are being broadcast a bit like a radio into other people's heads. OK. And are there any other primary symptoms? Yes, there's there's quite a list.
The next there's delusions of control, influence or passivity. These are beliefs that somehow you are being affected by an external agency or someone else. So you believe that you're being controlled, your movements are being controlled, your thoughts are being controlled, your emotions are being controlled somehow, maybe telepathically or by some other method. Are there any other symptoms? Yes, delusional perception is the primary symptom.
And this is an interesting symptom which is thought to occur at the onset of a psychotic episode where it is you have it a normal perception that's followed by a delusional interpretation of that normal perception.
Can you give me an example of delusional perception? An example of this might be seeing a red car, for instance, walking down the street when you walk down the street and then come to believe that seeing red car means that you're being followed by the MiFi, for instance, we've covered quite a number of primary symptoms. I'll just run through them. So it's thought I go in session withdrawal or broadcast also delusions of control, influence or passivity and delusional perception.
Are there any other primary symptoms? Yes, there are this. This group hears about hallucinations. There are specific hallucinations which are auditory and they are quite specific and they're for schizophrenia. And they include hallucinatory voices giving running commentary of what the person is doing in a given moment. So, for instance, talking about the fact that cooking dinner and making ourselves a cup of tea and then sitting down watching TV.
So it's running commentary. Another example of a hallucination, it's primary symptom is third person hallucinations, which is when a number of different voices are talking about the patient. And the last primary symptom, which is a hallucination, is that of a voice coming from another part of their body. For instance, their little toe is speaking to them.
Are there any other primary symptoms or have we covered them on the last one is a persistent delusion which is culturally inappropriate or impossible and classically has a bizarre nature to it. You say classically it has a bizarre content, but I suppose, of course, it might be a fairly ordinary content and that might make it quite difficult to detect. Yes. For instance, the fact that I might be going out with the Queen is theoretically possible and therefore not a primary symptom.
The fact that I might be the Queen is impossible and therefore is a primary symptom if it is persistent and culturally inappropriate. Thanks. What about the secondary symptoms? Can you tell me what those are? Yes. Secondary symptoms start with persistent hallucinations of any modality within any sense.
For instance, an olfactory or smell or visual hallucination, for instance, which is accompanied by fleeting or harmful delusion thought disorder, which is well present, says incoherent or irrelevant speech, but can often be experienced confusion by the patient, catatonic behaviour, which is a disturbance of psychomotor function and actually can be observed in a variety of disorders and negative symptoms, including apathy, blunting of emotions and social withdrawal.
Can you say a little bit about the prognosis of schizophrenia? Yes, schizophrenia is a major cause of disability. And although most people with schizophrenia live independently, they do often require some degree of ongoing management for mental health services and community support services. People having a first episode of psychosis roughly have a one in three chance of a good long term outcome with no further episodes.
Another third tend to have a relapsing remitting course, and roughly the last third of a percent have more of a poor outcome with some ongoing residual symptoms. Are the factors that affect prognosis include response to antipsychotic medication, ongoing drug use or life stresses, and frequent exposure to situations with a high expressed emotional content? Can you say what you mean by that? Yes, it's really important to have a low stimulus environment.
It's important that patients who have schizophrenia aren't exposed to, for instance, difficult arguments or fights or situations with a high emotional content. Does that make sense? Yeah, I think that yes. Does schizophrenia affect life expectancy? Yes. Schizophrenia does result in a decreased life expectancy of between 12 and 15 years.
And although this is primarily because of its association with obesity and sedentary lifestyles and smoking, suicides also plays a role in increasing the risk, although not as much as with bipolar disorder, people with schizophrenia have an increased risk of cardiovascular disease. And that's why promoting good fiscal health is really important and being aware of the risks associated with some of the long term antipsychotic medication we give patients.
Because of these factors, it's really important that metabolic monitoring such as fasting, lipids, glucose amongst all the blood tests should be performed every three to six months. Can you actually cure schizophrenia? Well, no, you can't. But there are effective treatments that can significantly improve symptoms. The most suitable paradigm potentially for think about management of schizophrenia is that of chronic disease management.
It's a bit like managing diabetes in a way. You can't cure diabetes, but you can you can. You manage it very effectively. It's an ongoing condition. Schizophrenia requires long term medication and lifestyle modification, but with the correct package, the person can do very well. It's good to have an encouraging message. I think it is a condition which can be very difficult, can be very disabling. So it's good to know that with the right support, people can live well.
Could you say a little bit more about the management? And first, tell me a bit about the pharmacological management. The mainstay of treatment pharmacologically is antipsychotic medication. Those, interestingly, little evidence for any difference in the efficacy and effectiveness of the different antipsychotics. We talk about first generation and second generation antipsychotics.
A lot of actually the main way that they differ is not necessarily in their efficacy, but more in the different side effects that they give. So nosecone actually suggests that you should discuss with the patient what medication would most suit them by reviewing each medications side effect profile.
Can we say what the side effects are with each of these groups of drugs? Yes, most antipsychotics do give you some level of sedation, but the two main groups of psychotics each have their own characteristic side effect profile. First generation antipsychotics such as Haloperidol, they have movement side effects.
We call these extra pyramidal side effects. They're called experimental side effects because they affect the pathways in the brain and the spine to do with movement that are not the pyramidal tracts. And it's extra pyramidal and the second generation of psychotics such as olanzapine Oncotype End tend to cause more weight gain and tend to be more sedative again over and above the first generation of psychotics. What would happen if antipsychotic medication isn't effective?
If a patient has been trialled on two antipsychotics at a reasonable dose for at least eight weeks and remains experiencing significant symptoms, then we would look to thinking about the medication called Klonopin, which has been proven to be effective in treatment resistant schizophrenia. What's been used is restricted because it has a serious side effect of causing a great deal of psychosis.
So. We use clozapine and it's actually a very good medication, but we need to several types of monitoring before they start clozapine and then we need to monitor their full blood count every week for six months and then every other week for the year and then monthly thereafter, after we've tried clozapine, we would move towards different combinations of antipsychotics. But this really is best avoided if possible, given the risks associated with combinations of antipsychotic medications.
And in this case, if we do use polypharmacy, then extra physical monitoring of the patient is required. Given some of the side effects associated with antipsychotics, with psychological therapies be appropriate for schizophrenia, yes, psychological treatments would be appropriate. But I think it's important to realise that patients do need to have pharmacological therapies that mainstay of treatment, psychological treatment would be seen as additional to the pharmacological intervention.
And CBT can be used in schizophrenia and has been seen to help reduce anxiety and paranoia associated with chronic psychotic symptoms. So CBT is targeting the symptom of the psychotic symptoms, particularly in how patients experience those as a way of reducing the distress caused by them. That's right. CBT doesn't challenge the delusions necessarily or the experience of hallucinations.
It rolls with the experiences the patient experience has and says, okay, well, if you do feel followed all the time, how can we help you with that belief? And other psychological treatment is family therapy, which, as I mentioned earlier, about high expressed emotions, family therapy as a specific intervention to try and reduce that. If I expressed emotions are present in a patient's family, it can seriously affect their prognosis.
How about social interventions? Can they be helpful for schizophrenia? Well, yes. Social management should always be a fundamental part of a patient's care package. Schizophrenia can be socially isolating and can lead to difficulties in maintaining independence. And for that reason, a social worker can help sorting out their benefits and their housing, and occupational therapist can help structured activities and monitor safety in the home environment.
And a support group can help with a patient's recovery as can ensure that the patient has adequate employment support and advice. Is there anything else that we should think about in terms of management? Well, the fact that the experience of being psychotic can be so very alarming and distressing, it can't that can lead to the patient posing a significant risk to themselves and others.
And this alongside the frequent lack of insight that is associated with schizophrenia coming admission to hospital is required. It may also be that the Mental Health Act is needed to admit the patient against their will for assessment and treatment. But admission is usually reserved for those cases where community management has failed or the patient poses significant risks to themselves or others. Before we finish. Are there any final points that you'd like to make?
Well, I think what mustn't be forgotten is that if the patient has a carer, then reviewing the carers needs is important as well as a psychotic illness can have a big impact on those closest to the patients. So in this case, the current assessment and referral to the care of support group can be very helpful. Thank you very much. That was a good overview, I think, of the causes of schizophrenia and also the approaches to treatment and management.
I hope that's been useful for our listeners. Thank you very much.