Schizophrenia is a chronic brain disorder that affects about one percent of the population. When schizophrenia is active, symptoms can include delusions, hallucinations, trouble with thinking and concentration, and lack of motivation. However, when these symptoms are treated, most people with schizophrenia will greatly improve over time.

While there is no cure for schizophrenia, research is leading to new, safer treatments. Experts also are unraveling the causes of the disease by studying genetics, conducting behavioral research, and by using advanced imaging to look at the brain’s structure and function. These approaches hold the promise of new, more effective therapies.

The complexity of schizophrenia may help explain why there are misconceptions about the disease. Schizophrenia does not mean split personality or multiple-personality. Most people with schizophrenia are not dangerous or violent. They also are not homeless nor do they live in hospitals. Most people with schizophrenia live with family, in group homes or on their own.

Research has shown that schizophrenia affects men and women about equally but may have an earlier onset in males. Rates are similar in all ethnic groups around the world. Schizophrenia is considered a group of disorders where causes and symptoms vary considerable between individuals.  Diagnostic and Statistical Manual of Mental Disorders, (DSM-5), 2013

What is schizophrenia? Schizophrenia is a major mental illness affecting the normal functioning of the brain. It is characterized by psychotic symptoms and a diminished range of expressions of emotion.

When the disease is active, it can be characterized by episodes in which the patient is unable to distinguish between real and unreal experiences. As with any illness, the severity, duration and frequency of symptoms can vary; however, in persons with schizophrenia, the incidence of severe psychotic symptoms often decreases during a patient’s lifetime. Not taking medications, use of alcohol or illicit drugs, and stressful situations tend to increase symptoms.

Researchers believe that a number of genetic and environmental factors contribute to causation, and life stresses may play a role in the disorder’s onset and course. Since multiple factors may contribute, scientists cannot yet be specific about the exact cause in individual cases. Since the term schizophrenia embraces several different disorders, variation in cause between cases is expected.

  • Worldwide prevalence estimates range between 0.5% and 1%. Age of first episode is typically younger among men (about 21 years of age) than women (27 years). Of persons with schizophrenia, by age 30, 9 out of 10 men, but only 2 out of 10 women, will manifest the illness.11
  • Persons with schizophrenia pose a high risk for suicide. Approximately one-third will attempt suicide and, eventually, about 1 out of 10 will take their own lives.11
  • A Canadian study found that the direct health care and non-health care costs of schizophrenia were estimated to be 2.02 billion Canadian dollars in 2004. This, combined with a high unemployment rate due to schizophrenia and an added productivity and morbidity and mortality loss of 4.83 billion Canadian dollars, yielded a total cost estimate of 6.85 billion in U.S. and Canadian dollars.12
  • The economic burden of schizophrenia is particularly great during the first year following the index episode, relative to the third year onward. This finding suggests the need for improved monitoring of persons with schizophrenia upon initial diagnosis.13

How common is schizophrenia? Widely accepted figures place the incidence of schizophrenia at about one in 100 people across all populations. Recent research challenges this and suggests that incidence may be significantly lower. It also shows that incidence is higher in males, in urban communities and among migrants. The most common time of onset for males is between 18 and 25 years and for females between 25 years and mid-30s. What causes schizophrenia? No single cause has been identified but several factors are believed to contribute to the onset of schizophrenia in some people. Both the onset and the course of schizophrenia can be viewed in terms of stress-vulnerability. A variety of biological, psychological and social factors can influence vulnerability to the onset of psychosis and vulnerability to relapse (see over). It is recognized that stressful incidents often precede the onset of schizophrenia.

What are the symptoms? The symptoms of schizophrenia are generally separated into the following categories:

POSITIVE SYMPTOMS are experiences and behaviors that have been added to the person’s normal way of functioning

• Hallucinations are distortions of the senses that are very real to the person. The brain hears, sees, smells, tastes or feels things that are not there in the external world:

– Hearing voices – Food tasting strange – Seeing things that aren’t real

• Delusions are fixed and false beliefs – e.g. something outside of me is controlling my thoughts

• Disorganized speech

• Disorganized behavior

NEGATIVE SYMPTOMS take away something from a person’s experience of the world. Negative symptoms are sometimes difficult to evaluate because they may be a result of a number of other factors such as a consequence of positive symptoms, medication side-effects and depression. The distinction requires sound clinical judgement

Diminished range of emotional expressiveness (most of the time)

• Reduced speech

• Inability to initiate and sustain goal-directed activities


• Disorganized thinking

• Impaired executive function affecting:

– poor concentration and focus – limited response to social cues – difficulty prioritizing and organizing

These symptoms must be persistent for six months before a diagnosis of schizophrenia will be given.

Risk factors for the development of schizophrenia Biological factors • Family history (genetics) – A family history of psychosis and certain personality disorders are associated with an increased risk of vulnerability to schizophrenia. • Physical abnormality of the brain – there is some evidence which suggests that people with schizophrenia have some alterations in brain shape (enlarged ventricles, smaller hippocampus). • Chemical imbalance – there is some evidence to suggest that the chemical systems involving the neurotransmitters dopamine and glutamate are involved. • Neurodevelopmental factors Personal attributes • Poor social and coping skills • Poor communication skills Environmental stress Schizophrenia is not a stress-related illness, but stress can interact with other risk factors to trigger acute (psychotic) episodes of the illness. Stress-inducing activities and events include substance use, work/school problems, rejection Associated behaviour Remember, these behaviours are out of keeping with the person’s normal value system by others, family conflicts, low social supports and major life events. None of the risk factors are the cause of schizophrenia, but the vulnerability to schizophrenia (and relapse) increases for people with a number of risk factors present. Protective factors • Good coping skills • Good social supports • Medication


Though there is no cure for schizophrenia, many patients do well with minimal symptoms or periods of recovery. Drug treatment can reduce symptoms and greatly reduce future relapses. Psychological treatments such as cognitive behavioral therapy or supportive psychotherapy may reduce symptoms and enhance function, and other treatments are aimed at reducing stress, supporting employment or improving social skills. Treatment can help many people with schizophrenia lead highly productive and rewarding lives. As with other chronic illnesses, some patients do extremely well while others continue to be symptomatic or have impaired ability to function.

A variety of antipsychotic medications are effective in reducing the psychotic symptoms present in the acute phase of the illness, and they also help reduce the potential for future acute episodes. Before treatment can begin, however, a psychiatrist should conduct a thorough medical examination to rule out substance abuse or other medical illnesses whose symptoms mimic schizophrenia.

Diagnosis and treatment can be complicated by substance misuse. People with schizophrenia misuse drugs more often than the general population. Substance misuse also reduces the effectiveness of treatment for schizophrenia. If a person shows signs of addiction, treatment for the addiction should occur along with treatment for schizophrenia.

Recovery and Rehabilitation

After the symptoms of schizophrenia are controlled, therapy can help people manage the illness. It can help people learn social skills, cope with stress, identify early warning signs of relapse and prolong periods of remission. Because schizophrenia typically strikes in early adulthood, individuals with the disorder often benefit from rehabilitation to help develop life-management skills, complete vocational or educational training, and hold a job. For example, supported-employment programs have been found to help persons with schizophrenia obtain self-sufficiency. These programs provide people with severe mental illness with competitive jobs in the community.

Many people living with schizophrenia receive emotional and material support from their family. Therefore, it is important that families be provided with education, assistance and support. Such assistance has been shown to help prevent relapses and improve the overall mental health of the family members as well as the person with schizophrenia.

Living with Schizophrenia

Optimism is important and patients, family members and mental health professionals need to be mindful that many patients have a favorable course of illness, that challenges can often be addressed, and that patients have many personal strengths that can be recognized and supported.

Related Conditions

  • Schizoaffective disorder
  • Delusional disorder
  • Brief psychotic disorder
  • Schizophreniform disorder
  • Catatonia

Andreasen NC, Black DW. Introductory Textbook of Psychiatry. (4th ed.). Arlington, VA: American Psychiatric Publishing, Inc., 2006
Sadock BJ, Sadock VA. Kaplan & Sadock’s Synopsis of Psychiatry: BehavioralSciences/Clinical Psychiatry (10th ed.). Philadelphia, PA, Lippincott, Williams, & Wilkins;2007.

More detail on mental health/mental illnesses may be found at: http://www.nimh.nih.gov/health/index.shtml or www.samhsa.gov/

%d bloggers like this: