Schizophrenia is a chronic mental health disorder that affects the person’s way of thinking, perception, behavior, and emotional responsiveness.  A person with schizophrenia may be unable to distinguish between what is real and what is imaginary. Schizophrenia often causes psychotic episodes in which the patients suffer from hallucinations or delusions.

Schizophrenia can be classified into several types depending upon the symptoms. Paranoid schizophrenia is marked by delusions and auditory hallucinations, while disorganized schizophrenia is characterized by disordered thought processes, speech and behavior. Catatonic schizophrenia is characterized by extremes in movement ranging from hyperactive agitation to immobility.

Residual schizophrenia describes patients whose symptoms had become less severe or minor. Simple schizophrenia is associated with gradual development of negative symptoms and a marked decline in performance.

Sometimes, the symptoms of schizophrenia do not clearly fall into a category and is accordingly called undifferentiated schizophrenia.

The cause of schizophrenia is not yet fully understood; however, it may be the result of a combination of genetic, brain chemistry, and environmental factors.

People who have schizophrenia are genetically predisposed to have the disorder, but having these genes does not necessarily mean a person will develop schizophrenia.

An imbalance of neurotransmitters, particularly, dopamine and glutamine may be involved in the development of schizophrenia.

Environmental factors, such as viral infections, prenatal and perinatal problems and father’s age, play a role in the development of schizophrenia, especially in those who are genetically predisposed.

The pathophysiology of schizophrenia is not very well understood. The most commonly supported theories in this regard have implicated anatomic, neurotransmitter, and immune system abnormalities.

The symptoms of schizophrenia fall into three categories. Positive symptoms include any alterations in behaviors or thoughts, such as hallucinations or delusions, while negative symptoms are an absence of emotional responses normally seen in healthy people. The third category, cognitive symptoms, is associated with thinking processes, and include difficulty focusing and poor memory.

No single test can positively diagnose schizophrenia. Diagnosis of schizophrenia is usually done by a mental health specialist through the criteria found in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. This usually involves evaluating the patient’s symptoms, and performing tests to rule out other possible causes of the symptoms, such as drug abuse or a medical condition.

Schizophrenia is requires lifelong treatment. Managing the disorder usually includes the use of medications and psychosocial therapy.

Left untreated, schizophrenia can result in severe complications that affect every area of life, such as work and relationships.

Prevention of schizophrenia is not possible, but early detection and treatment can help people with the disease lead normal lives.

Schizophrenia is a severe, long-term mental health disorder which affects the way of thinking, perception, behavior, and emotional responsiveness.  A person with schizophrenia may have trouble distinguishing between what is real and what is imaginary. Schizophrenia often includes psychotic experiences in which the affected person loses touch with reality and suffers from hallucinations or delusions.

Schizophrenia is commonly thought of as split personality or multiple personality, but this is a misconception. People with schizophrenia are mostly not violent and pose no danger to others.

Schizophrenia can be classified into different types depending on the symptoms the patient displays.  It is worth mentioning that the classifications of schizophrenia have been removed from DSM-5 because they appear to be unhelpful in providing better treatment or predicting treatment response. The subtypes include:

1) Paranoid schizophrenia is characterized by the presence of positive symptoms, specifically delusions or hallucinations, which are often accompanied by fears of persecution. Patients with this type either do not present other symptoms of schizophrenia such as disorganized speech, flat affect, or disorganized behavior, or these symptoms are less common than the positive symptoms.

2) Hebephrenic schizophrenia, or disorganized schizophrenia, is a type characterized by inconsistent mood and flattened affect. Patients with this type display lack of goal directed behavior, in addition to disorganized speech and prominent thought disorder.

3) Catatonic schizophrenia is an uncommon subtype because it is believed to be the result of untreated schizophrenia. This type is characterized by constant abnormal motor behavior, i.e. a decrease in the ability to move or an increase in activity. Patients may also senselessly imitate the movement or speech of people around them.

4) Undifferentiated schizophrenia is a type of schizophrenia that does not fit into the three previous categories. People with this type of schizophrenia show a range of symptoms that are not identifiable enough to be classified into other subtypes.

5) Residual schizophrenia is a term used to describe a patient who is not experiencing obvious positive symptoms such as delusions, hallucinations or disorganized speech, but is experiencing constant negative symptoms that points towards schizophrenia.

6) Simple schizophrenia is often associated with a significant loss of personal motivation, gradual development of negative symptoms and a distinct decline in social, academic and employment performance.

The exact cause of schizophrenia is not known. Research indicates a combination of factors that play a role in developing the disorder. Factors that may lead to schizophrenia include physical, genetic, psychological, brain chemistry and environmental factors.

Neuroimaging may show changes in brain structure and the central nervous system of schizophrenia patients, but it is uncertain whether these changes are significant.

Although the precise cause of schizophrenia is unknown, several factors contribute to the risk of developing or triggering the disease. These factors include:

1) Genes and environment

Scientists have implicated many genes that increase the risk of developing schizophrenia, but found no specific gene that directly causes its.

According to the UK National Health Service, in identical twins sharing the same genes, if one develops schizophrenia, the other has a 50% chance of developing it too. This shows that the disorder is only partly inherited.

Scientists also believe that interactions between genes and environments are necessary for schizophrenia to develop. Environmental factors may involve:

• Exposure to viruses

Viral infections or immune disorders increase the risk of developing the disorder. For example, babies whose mothers get sick with flu while pregnant are at at an increased risk of developing schizophrenia later in life.

• Prenatal and Perinatal Problems.

Problems before or during birth increase the risk for schizophrenia. These problems may include low birth weight, malnutrition, premature labor, and a lack of oxygen due to birth complications.

• Psychosocial factors

Stressful life events may be a trigger to the development of schizophrenia in susceptible people. Stressful life events include bereavement, losing a job, the end of a relationship, or any type of abuse.

• Father’s age

Some studies have found a link between increased paternal age and a greater risk of schizophrenia, possibly due the greater chance of genetic mutations in the sperm.

2) Brain chemistry

Scientists have observed an imbalance in brain chemicals in patients with schizophrenia. These brain chemicals, called neurotransmitters, include dopamine, glutamine and serotonin, convey messages between nerve cells in the brain.

3) Brain structure

Problems with brain development while in the womb may causes disconnections and damages in chemical pathways in the brain which may later lead to schizophrenia.

4) Age

Usually, schizophrenia develops between the ages of 16 to 30 years, but can start at any age. Only rare cases of schizophrenia develop before adolescence and after the age of 45.

5) Gender

Although schizophrenia develops in men and women at equal rates, the disorder tends to develop at an earlier age in men and presents more severe symptoms.

6) Drug abuse

Several studies have established a link between drug abuse and an increased risk of schizophrenia. Drugs do not seem to be a direct cause of schizophrenia, but drugs such as cannabis, cocaine, and amphetamines, may trigger symptoms of schizophrenia in people at risk.

The pathophysiology of schizophrenia is still poorly understood. Scientists have proposed several theories on pathophysiology of schizophrenia, most common of which are the anatomic, neurotransmitter, and immune system abnormalities.

1) Anatomic abnormalities

Images of the brains of patients with schizophrenia show differences in brain structure from those who do not have the disorder. For instance, the ventricles are somewhat larger in people with schizophrenia, and brain volume in medial temporal areas is decreased. Also, changes in the hippocampus have been observed.

2) Neurotransmitter system abnormalities

Imbalance in the neurotransmitter dopamine is the most likely factor in developing schizophrenia. The limbic system in the middle of the brain and the prefrontal cortex are likely areas of pathology, but research has implicated other major neurotransmitters and areas of the brain in schizophrenia.

Hypodopaminergic activity in the mesocortical system leads to negative symptoms, while hyperdopaminergic activity in the mesolimbic system leads to positive symptoms, and both may coexist.

Other research focuses on the N -methyl-D-aspartate (NMDA) subclass of glutamate receptors due to the fact that NMDA antagonists, such as phencyclidine and ketamine, can cause psychotic symptoms in healthy subjects.

3) Inflammation and immune function

An overactivation of the immune system, such as that results from prenatal infection or postnatal stress, may causes an overexpression of inflammatory cytokines and alterations in brain structure and function. That’s possibly why patients with schizophrenic have elevated levels of proinflammatory cytokines. Proinflammatory cytokines activate the kynurenine pathway, which metabolizes tryptophan into kynurenic and quinolinic acids. These acids regulate NMDA receptor activity and may also help in dopamine regulation.

Metabolic disturbances such insulin resistance are common in patients with schizophrenic, and they have been linked to inflammation. Therefore, inflammation might be linked to both the psychopathology of schizophrenia and to the metabolic disturbances commonly seen in the schizophrenic patients with schizophrenia.

The severity, duration and frequency of symptoms can vary. The symptoms of schizophrenia fall into three categories:

1) Positive symptoms: “Positive” symptoms are behaviors and ways of thinking not generally seen in healthy people, i.e. the patient did not have them before developing the disorder. These symptoms include:

• Hallucinations: Usually, hallucinations involve seeing or hearing things that are not real. Although hallucinations are mostly auditory in which the patient hears voices that do not exist, hallucinations can affect any of the senses. The person experiencing hallucinations feels that they are very.

• Delusions: Delusions are best described as false beliefs that have no basis in reality. The onset of delusions can be sudden, or they can develop over weeks or more. Delusion that the person is being persecuted or that others around them are trying to harm them are common in patients with schizophrenia.

• Thought disorders (speech): Disorganized thinking in patients with schizophrenia is usually most apparent in its effects on speech. As a result of this, other people cannot have effective communication with the patient because, for example, the patient would provide answers that are unrelated to questions.
• Movement Disorders: Movement disorders can be mild to severe, ranging from repetitive body movements to a complete lack of motion or responsiveness.

2) Negative symptoms: These symptoms are associated with disruptions to normal emotions and behaviors, i.e. the patient had normal emotions and behaviors before schizophrenia developed.  Negative symptoms include: 

• Flat affect, or withdrawal of emotion including absence of facial expressions or voice monotone
• Reduced feelings of pleasure in everyday life
• Difficulty beginning and continuing with activities, in addition to a lost interest in life and activities, including relationships and sex
• Reduced speech as the patient becomes less likely to initiate conversations, and starts to feel uncomfortable around people.

3) Cognitive symptoms: Cognitive symptoms of schizophrenia vary in severity from one patient to another, and are associated with changes in memory or other aspects of thinking. The patient may become unable to understand new information and use it in making decisions, or may have trouble focusing or paying attention. 

Negative symptoms of schizophrenia often appear several years before someone with schizophrenia experiences their first acute psychotic episode, which is predominately positive symptoms.

There are no blood tests or scans that can positively confirm the disease. A mental health professional will diagnose schizophrenia if it meets the diagnostic criteria presented in the DMS-5:

• At least two of the following symptoms are present for most of the time in a 1-month period:
  • • Delusions
    • Hallucinations
    • Disorganized speech
    • Grossly disorganized or catatonic behavior
    • Negative symptoms

• Decreased functioning in at least one area of life, such as work or relationships, most of the time since the onset of the disorder.
• Symptoms that continue for six or more months, with at least one month of symptoms from the first criterion.
• Other mental illnesses have been excluded, especially schizoaffective disorder, and depression or bipolar disorder with psychotic features.
• Other medical conditions have been excluded, and the symptoms are not attributable to substance use.
• People with a history of autism or communication disorders that started in their childhood are only diagnosed with schizophrenia if they present prominent delusions or hallucinations and other symptoms of schizophrenia for at least a month.

Schizophrenia requires lifelong treatment, even when symptoms have subsided. Treatment of schizophrenia focuses on eliminating the symptoms so that a patient with schizophrenia can lead a productive life. These treatments include:

1) Antipsychotic medications 

Antipsychotic medications are effective in eliminating the signs and symptoms of schizophrenia. They are thought to control symptoms by affecting the brain neurotransmitter dopamine.

Doctors and patients can work together to find the best medication, and the right dose. The antipsychotic medications include:

• Second-generation antipsychotics (Atypical antipsychotics)

These are also called newer-generation medications, and are generally preferred because they pose a lower chance for side effects than first-generation antipsychotics. Second-generation antipsychotics include: 

• Aripiprazole  
• Asenapine  
• Brexpiprazole  

• First-generation antipsychotics (Typical antipsychotics)

 
Neurological side effects are generally more common in first-generation antipsychotics. These include the possibility of developing a movement disorder that may or may not be adjustable. First-generation antipsychotics include: 
 

• Chlorpromazine
• Fluphenazine 
• Haloperidol
• Perphenazine

2) Psychosocial Treatments

 
These include a combination of psychological and social interventions that are most helpful when merged with antipsychotic medication. They may include: 

• Individual therapy: Psychotherapy may help the patient cope with positive, negative and cognitive symptoms, and successfully manage the illness.  
• Social skills training: This encourages the patient to participate in daily activities that include communication and social interactions to improve social skills.  
• Family therapy: This helps families of patients with schizophrenia in acquiring support and education in dealing with the disorder. This can have positive effects on the patient’s ability to cope with it, and help to prevent relapses. Not only does family therapy help improve the overall mental health of family members, but it helps the person with schizophrenia. 
• Vocational rehabilitation: Because schizophrenia usually starts at a time when people’s careers are developing, it may have significate effects on career advancement. Vocational rehabilitation helps people with schizophrenia prepare for, find and keep jobs.. 

4) Hospitalization 

Some patient with schizophrenia need to be hospitalized during times of severe symptoms to ensure their safety, and that they are getting proper nutrition, adequate sleep and basic hygiene.

Usually, a treatment model that integrates medication with psychosocial, family , vocational therapies will be adopted to help reduce the symptoms and improved the patients quality of life. 

Untreated schizophrenia may lead to more severe symptoms. Other complications associated with schizophrenia include:  

• Suicide: Patients with schizophrenia are more likely to think about and attempt suicide. Many factors are responsible for this, including social isolation, discrimination, and stigma. 
• Depression: Clinical depression is common among people with schizophrenia. 
• Anxiety disorders: Patients with schizophrenia may go on to develop anxiety disorders, such obsessive-compulsive disorder. 
• Substance abuse: Many people with schizophrenia abuse alcohol or drugs, a dangerous complication as it may increase the severity of symptoms by decreasing the probability that the patient will continue taking medications. 
• Nicotine dependence: Most patients with schizophrenia smoke. It is the most common form of substance abuse between people who have schizophrenia. 
• Normal functioning: Schizophrenia affects the patient’s ability to work or attend school, and lead to problems functioning normally.
• Legal and financial problems: Patients with untreated schizophrenia are more likely to suffer from poverty, homelessness, and incarceration.
• Health and medical problems: Untreated patients with schizophrenia are less able to care for themselves, and are at risk for developing more severe medical illnesses. Substance abuse may also lead to other medical problems, such as heart disease, cirrhosis, and malnutrition. 
• Aggressive behavior: People with schizophrenia are not usually violent; however, substance abuse in schizophrenic patients increase the risk for violence.

There is no sure way to prevent schizophrenia. However, learning more about risk factors and triggers, such as drug abuse and social isolation, may help people get an early diagnosis and receive proper treatment, which help in getting symptoms under control before serious complications develop, and  prevent relapses or worsening of schizophrenia. 

Schizophrenia is an incurable brain disorder. Early diagnosis and proper treatment, however, greatly improve the prognosis and reduce the effects of schizophrenia on the patient’s life.  

The US Journal of Psychopharmacology has published a review showing that people with schizophrenia have a 5% lifetime risk of suicide. Other factors that contribute to increased mortality include lifestyle issues such as cigarette smoking, poor nutrition, and lack of exercise, and perhaps poorer medical care and complications of medications.

According to the American Psychiatric Association, research has shown that schizophrenia affects men and women equally, but the diseases starts earlier in men. Men usually experience their first episode of schizophrenia in their early 20s, while for women it usually happens in their late 20s or early 30s. Rates are similar in all ethnic groups around the world.

A study published in the international journal Schizophrenia Research has shown that the lifetime prevalence of schizophrenia has generally been estimated to be approximately 1% worldwide. However, a systematic review published in a US Journal, PLOS Medicine, looked into 188 studies drawn from 46 countries and found a lifetime risk of 4.0 per 1000. Prevalence estimates from countries considered least developed were significantly lower than those from countries classed as emerging or developed.

The World Health Organization reports that there are more than 21 million people in the world affected by schizophrenia, and that 50% percent of patients do not receive the proper care.