Hello and welcome back to module five, schizophrenia spectrum disorders. This is lecture to prevalence, impact and related disorders. In the first part of this lecture, we will talk about the prevalence and impact of schizophrenia. Then we will go through a brief overview of disorders that are related to schizophrenia and categorized as schizophrenia spectrum disorders. Approximately one and 100 people in the world have schizophrenia. This means 21 million people struggle with disorder throughout the world, including 3.6 million people in the US. Schizophrenia impacts men and women equally, the average age of onset is 23 for men and 28 for women. The disorder is diagnozed more commonly among people who are living at lower income levels, although it is not known whether poverty represents a trigger that can activate schizophrenia or whether people with schizophrenia tend to live at lower income levels because of the impact of the disorder on their ability to work. Schizophrenia is considered a serious mental illness and it has a devastating impact on the lives of people who struggle with it. About one in 4 people with schizophrenia attempt suicide and about one in 20 die by suicide. People with this disorder have a much higher risk of medical illness and in fact their lifespan is 10-20 years shorter than people who do not have the disorder. While the severity of the disorder varies from person to person, it is generally agreed that it has three distinct phases that can be seen in all people who struggle with it. The first phase is called the prodromal phase. In the prodromal phase, the person experiences the beginning of symptoms that will later develop into the full symptoms of schizophrenia. These prodromal symptoms are much less severe. A person may feel their ears are playing tricks on them because they hear noises they cannot account for. They may feel suspicious of other people and socially withdraw from family and friends. They may have some unusual thoughts and occasionally behave in odd ways. Most of these early symptoms are not apparent to other people. However, the person's overall functioning does begin to deteriorate in the prodromal phase, and friends and family may begin to worry, although they don't understand what the person is experiencing. During the active phase of the disorder, the symptoms become dramatic and apparent to others. After six months of significant symptoms, a diagnosis of schizophrenia is given. Treatment generally begins in the active phase, although if it is caught early, treatment can begin in the prodromal phase. The third phase is the residual phase, which is characterized by a reduction and positive symptoms and an improvement in overall functioning of quality of life. Some negative symptoms may remain. It is estimated that about 25% of people diagnozed with schizophrenia will recover completely, while the remaining 75% struggle with symptoms for the rest of their lives. Before we move on to discussions of models, treatment and multicultural considerations of a schizophrenia, let's spend a little time talking about a few related disorders. Sometimes people experience symptoms that are similar in many ways to schizophrenia, but they do not fit exactly under that label. Researchers and clinicians identify them as separate and distinct psychological disorders, yet classify them all under the heading schizophrenia spectrum disorders. Categorizing them in this manner, communicates that all of these disorders are similar to each other in many ways. Let's take a look at the disorders included under this diagnostic umbrella. Sometimes people experience all the symptoms of schizophrenia, but the symptoms persist for a shorter period of time. While someone must experience symptoms continuously for at least six months to be diagnozed with schizophrenia, a person whose symptoms remit after more than one month, but less than six months after their onset is diagnozed with schizophreniform disorder. At times the symptoms remit due to treatment and other times they remit with no treatment at all. Lifetime prevalence of schizophrenia form disorder is estimated at 0.2% of the general population. Schizoaffective disorder combines elements of schizophrenia and a major mood disorder. When a person has a major mood disorders such as major depressive disorder or bipolar 1 disorder and they also experience a period of time lasting at least two weeks. When they experience all the symptoms of schizophrenia without having any mood symptoms at the same time, they're diagnozed with schizoaffective disorder. The lifetime prevalence of this disorder and the general population is not currently known. Delusional disorder occurs when a person possesses a persistent false belief but does not have any of the other symptoms associated with schizophrenia. There are no hallucinations, negative symptoms or disorganized symptoms present. Researchers have identified several subtypes of delusional disorder. Grandiose delusional disorder involves the belief that one is a powerful or has a special relationship with a famous person or deity. Persecutory delusional disorder is diagnozed when a person believes that an individual, group of people or entity is trying to harm them in some way. Somatic delusional disorder involves the belief there's something wrong with the body, such as a physical defect or a medical condition. Jealous delusional disorder is diagnozed when someone is convinced their partner is unfaithful to them. Finally, erotomanic delusional disorder occurs when a person believes they have a lot interest in a famous person or a person with higher social status. It's important to note that in all these types of delusional disorders, the delusions involve scenarios that could, in theory be true, but in reality are false. In this way, these delusions differ from the ones typically present in schizophrenia, which are much more likely to be bizarre. For example, a belief that one's thoughts are being broadcasted and picked up by cell phone towers all over the world. Shared psychotic disorder, also known by the french term Folie a deux or madness of two, occurs when an individual develops a delusion after spending an extended period of time with another person who already has a delusional disorder. There are some research suggesting that shared psychotic disorder may develop when two people, one of whom has a delusional disorder spends an extended period of time together, cut off from their community and other relationships. This circumstances makes a healthy person more vulnerable to developing the same delusion as the person with this disorder. Delusional disorders appear to be quite rare, with an estimated lifetime prevalence of 0.1% in the general population. At the same time, there's evidence that people with this disorder do not seek treatment voluntarily, which means the actual prevalence may be higher than currently estimated. Brief psychotic disorder is diagnozed when a person experiences symptoms of schizophrenia, such as delusions, hallucinations or disorganized speech or behavior that lasts no more than one month. Research suggests that extremely stressful events may activate a brief psychotic disorder. Once the disorder remit, the person returns to their previous level of functioning. The lifetime prevalence of brief psychotic disorder and the general population is not known at this time. This concludes our overview of psychological disorders that are related to schizophrenia and categorized under the umbrella schizophrenia spectrum disorders. As you can see from the research I've referenced, these disorders occur far less frequently than schizophrenia. Some occur so rarely that researchers can't provide an estimate for their prevalence. Schizophrenia, on the other hand, occurs in 1% of the general population, which, while a small percentage translates to large numbers of people. When we consider how devastating schizophrenia's impact is on the lives and functioning of the people it affects, this prevalence rate is even more significant. In the upcoming lectures, we will discuss the models for understanding schizophrenia, the major treatment modalities used to assist people with this disorder, and the sociocultural and multicultural considerations to keep in mind as we think about this disorder and its impact. We will close this module and the course with a final lecture in the foundations of empathic series.