Schizophrenia: Causes, Symptoms, Heredity

Schizophrenia: Causes, Symptoms, Heredity
Photo source: Getty images

Schizophrenia is a psychotic mental disorder. It interferes with people's thinking, perception, experiencing and acting in contact with the environment. Early diagnosis and treatment are important.


Schizophrenia is a severe chronic psychotic mental disorder that reduces a person's quality of life. It affects all domains of human thought, perception, experience and action in contact with the environment.

From an epidemiological point of view, there are no preventive measures for schizophrenia, which makes its early diagnosis and early initiation of adequate treatment all the more important.

Schizophrenia is often associated with the words mental illness, hallucinations, delusions, suicidia (suicide).


Schizophrenia is a chronic psychotic disorder that leads to significant changes in the patient's perception of reality because it is accompanied by hallucinations (perception) and delusions (thinking, interpretation).

It ranks among the most financially costly diseases in the world.
More than 21 million people suffer from it, regardless of race, culture or social class.

The lifetime prevalence of schizophrenia is 1-1.5%, with no proven difference between the sexes. It differs only in the time of onset, with onset typically occurring between 15 and 25 years of age in men and between 25 and 35 years of age in women. 

The risk of mortality and suicide is higher than in the general population.

How is schizophrenia classified and subdivided?

According to ICD-10, there are 9 basic subtypes of schizophrenia, for which the general criteria for a diagnosis of schizophrenia must of course be met, and in addition.

Forms according to the ICD:

  1. F20.0 Paranoid schizophrenia
  2. F20.1 Hebephrenic schizophrenia
  3. F20.2 Catatonic schizophrenia
  4. F20.3 Undifferentiated schizophrenia
  5. F20.4 Post-schizophrenic depression
  6. F20.5 Residual schizophrenia
  7. F20.6 Simple schizophrenia
  8. and F20.8 Other schizophrenia and F20.9 Schizophrenia, unspecified


Schizophrenia is caused by an imbalance of chemicals in the brain that provide communication between neurons, leading to perceiving (seeing/hearing/believing to be true) things that are not real.

The factors that create this imbalance are not yet fully understood.

Psychotic disorders are never triggered by a single cause, but by a combination of a number of sub-causes. Some are innate (heredity, the course of pregnancy), others are caused by the influences of the environment in which the sufferer lives and the events he or she has experienced.

Disease predispositions include hypersensitivity and increased vulnerability, so the quality of relationships with loved ones is important.

Only the disposition is inherited, not the disease itself.

If either parent suffers from schizophrenia, the likelihood that the child will also become ill is about 10%.

Most schizophrenics are people who use drugs (especially marijuana, methamphetamine or cocaine) or suffer from alcohol or nicotine addiction.

Groups at risk include:

  • people from socially disadvantaged backgrounds (or poor family backgrounds),
  • People from urban but poor backgrounds,
  • immigrants,
  • ethnic minorities,
  • people who were born after a complicated birth


Sudden and unexpected illness rarely occurs.

An outbreak may be preceded by a period of months to years during which the person gradually changes:

  • is withdrawn
  • breaks social contacts
  • communicates less well
  • speaks incoherently, to himself or herself
  • performs strange rituals
  • tends to be irritable
  • loses interest in the outside world
  • is experimenting with drugs

The world becomes incomprehensible to the sick person, he experiences a sense of loss of control over reality. Things become unclear and take on multiple or symbolic meanings.

A person at risk of the disease often remains without professional care for 1-2 years, while the first symptoms may appear as early as 2-6 years before help is sought.

Confused woman standing in a crowd of people, has a problem with the psyche, exaggerated sensitivity to light and sounds, noise.
Hypersensitivity to noise and light. Photo source: Getty images.


Diagnosis is based on medical history (changes in psyche and behaviour). It is determined on the basis of the clinical criteria mentioned in the course section.

Diagnosis of schizophrenia can take months or years.

Blood tests are important as part of treatment to determine the effects of substances.


The first attack of schizophrenia is difficult to predict.

Schizophrenia in pre-school children is very rare, as magical thinking is still prevalent in thinking, i.e. young children routinely make imaginary friends, making it very difficult to distinguish imaginary friends from visual hallucinations.

However, if the imaginary friends do not disappear by about 7 years of age, it is necessary to seek medical attention.

Most often, the first attack of schizophrenia occurs in puberty or early adulthood (before the age of 30). The first experimentation with illicit substances, such as recreational smoking of marijuana, which is often advocated by many, contributes enormously to the risk.

Marijuana has been shown to induce hallucinations, which can be a gateway to schizophrenia.

The risk of developing schizophrenia is also increased when family ties are weakened - for some young people, the trigger is the first time they leave home (for example, to go to high school or college) or a tragedy in the family. Many times the family denies the seriousness of the situation, tries to compensate for the problem on their own, and attributes the changes in behaviour to, for example, adolescence or drug use - usually because they are worried about psychiatry.

The first so-called warning signs are usually sleep disturbances, but also bizarreness in dressing or neglect of personal hygiene. He begins to reduce social contact, loses his sense of humour or becomes depressed. Mood is volatile, sometimes crying excessively, then laughing for no reason.

It is possible to notice personality changes.

Sensitivity to light and noise appears.

The clinical picture of schizophrenia is variable and may change over the course of the illness in its different phases.

General ICD-10 criteria for paranoid, hebephrenic, catatonic, and undifferentiated schizophrenia. At least one of the syndromes, symptoms and signs listed under 1.

Criterion 1 - at least one of the following:

  • thought echo, thought insertion, thought withdrawal, and thought broadcasting.
  • delusions of control, influence, or passivity, clearly referred to body or limb movements or specific thoughts, actions, or sensations; delusional perception.
  • hallucinatory voices giving a running commentary on the patient's behaviour, or discussing the patient among themselves, or other types of hallucinatory voices coming from some part of the body.
  • persistent delusions of other kinds that are culturally inappropriate and completely impossible, such as religious or political identity, or superhuman powers and abilities (e.g. being able to control the weather, or being in communication with aliens from another world).

Or at least two of the symptoms and signs listed under 2.

Criterion 2 -at least two of the following:

  • persistent hallucinations in any modality, when accompanied either by fleeting or half‐formed delusions without clear affective content, or by persistent over‐valued ideas, or when occurring every day for weeks or months on end;
  • breaks or interpolations in the train of thought, resulting in incoherence or irrelevant speech, or neologisms.
  • catatonic behaviour, such as excitement, posturing, or waxy flexibility, negativism, mutism, and stupor.
  • "negative" symptoms such as marked apathy, paucity of speech, and blunting or incongruity of emotional responses, usually resulting in social withdrawal and lowering of social performance; it must be clear that these are not due to depression or to neuroleptic medication.

They should be present most of the time during an episode of psychotic illness lasting at least one month (or in some cases for most of the day).

Since the manifestations of schizophrenia are diverse, they are divided into 4 groups:

  1. Positive symptoms:
    • hallucinations, delusions, catatonic symptoms, structural thought disorders and disorganized actions.
  2. Negative symptoms:
    • lack of emotional reactivity, hypobulia, ambivalence, poor speech, social withdrawal.
  3. Cognitive symptoms:
    • impaired attention and reduced speed of information processing, verbal learning and memory, and social cognition.
  4. Depressive symptoms can occur at any stage of the illness and are sometimes difficult to differentiate from negative symptoms and imply a high suicidal risk.

Recommendations for patients

It is necessary to follow the recommendations of the doctor and adhere to a regular regimen.

Recommendations for patients:

Maintain a regular sleep schedule.

Go to bed at around the same time every night and get up at around the same time every morning. Apparently, disrupted sleep patterns can kick-start mood disorders.

If you are going to travel to areas with a different time zone, consult your doctor beforehand.

Perform your usual daily activities.

Don't be lazy, but at the same time don't exert yourself too much.

Plan your activities!

Do not consume alcohol or other psychoactive substances (marijuana, methamphetamine, cocaine, LSD, but also drugs). Drugs and alcohol can trigger episodes of mood disorders and also affect the effectiveness of psychopharmacological treatment.

Sometimes alcohol and drugs can be a "tempting cure" for mood or sleep disorders, but virtually always they will only make the situation worse. If you have a problem with substances like these, talk to your doctor.

Also watch out for daily ingestion of small doses of alcohol, caffeine and some over-the-counter cold, allergy or pain medications. Even small doses of these substances can affect sleep, mood or interact with your medications.

Accept the support of family and friends.

Remember that it is not always easy to live with someone who has mood swings. If you all learn as much as you can about schizophrenia, it will be easier for you to alleviate the relationship problems that this disorder can cause. Even a "calmer" family will sometimes need outside help.

Try to reduce stress levels at work. Of course, you want to be the best you can be at work.

But remember, it is more important for you to avoid relapses!
Try to work at a certain hour so that you get to bed on time. 
Avoid shift work!

If the symptoms of a mood disorder are affecting your ability to work, talk to your doctor about whether to stop working altogether or just take a few days off. How openly you dedicate yourself to your employer and colleagues is up to you. If you are unable to work, a family member can tell your employer that you are not feeling well and that you are under medical care and will return to work as soon as possible.

Learn to recognize the "early warning signs" of new episodes.

Early warning signs are very individual, and the better you are at recognising the warning signs, the sooner you can be offered help.

Slight changes in mood, sleep, energy, self-esteem, sexual interest, concentration, willingness to work on new projects, thoughts of death (or sudden optimism), and even changes in style of dress and hairstyle can be early warning signs.

Pay special attention to your change in sleep patterns, as this is usually the first clue that something is wrong. And because loss of judgment can also be a sign of a new episode, don't be shy about asking your family to look for the first warning signs that you might have missed.

If you think the treatment is not working or is causing you unpleasant side effects, tell your doctor.

Do not stop taking and adjust the dosage of medication by yourself!

Symptoms that appear after discontinuation of the drug are usually much more difficult to treat. If things are not going in the right direction, don't be ashamed to ask your doctor to procure the opinion of another professional. It's normal to have doubts sometimes, and a consultation can be a great help.

Contact your doctor IMMEDIATELY

Contact your doctor IMMEDIATELY if you have:

  • suicidal thoughts
  • tendencies to aggression
  • mood swings, sleep or energy disturbances
  • symptoms related to side effects of the medicine
  • the need to take over-the-counter medicines such as cold medicines or painkillers
  • acute illness or if there has been a change in the use of your other medicines

Take suicidal thoughts seriously!

People suffering from schizophrenia are overly suspicious or may have hallucinations that encourage them to commit suicide, which ultimately leads to up to half of schizophrenics attempting suicide.

5 to 10 % of people with schizophrenia commit suicide.

Warning signs that the patient is contemplating suicide:

  • "final preparations" - saying goodbye to acquaintances, gifting favourite things to loved ones,
  • repeatedly talks about death and suicide,
  • sudden improvement in mood - may indicate that the person has "finally" made a decision and feels better because of it,
  • self-injury

If you suspect your loved one is suicidal, never leave them alone - stay with them or ask someone to. Also, remove dangerous items such as medications (even those he or she is taking; you may prefer to give them to him or her yourself) and sharp objects from his or her reach.


Schizophrenia as a mental disorder can be referred to from the first schizophrenic episode, but its onset can be both gradual and acute.

The subsequent course is variable, ranging from a single episode with full recovery, to persistent disability, to repeated episodes with varying degrees of recovery, to continuous variants with deepening of the residue.

Predictors (markers of success) of an adverse course include familial occurrence of the disease, lack of premorbid social adaptation, cognitive impairment, neurodevelopmental abnormalities and structural anomalies of the brain, male gender, earlier onset of onset, creeping development of the disease, low socioeconomic status, substance use, and duration of untreated psychosis.

Social impact

Schizophrenia is a lifelong illness with a high tendency to chronicity.

In the case of long-term remission in an appropriate social environment, the rate of decline in earning capacity is 35-45%.

Modern psychiatric care is socially oriented, so we provide treatment, aftercare and rehabilitation with the aim of integrating the patient back into society.

About half of those diagnosed with schizophrenia will have a significant improvement over the long term with no further relapses, and a small proportion of these will recover completely. The other half will have a lifelong impairment. In severe cases people may be admitted to hospitals. Social problems such as long-term unemployment, poverty, homelessness, exploitation, and victimization are commonly correlated with schizophrenia. Compared to the general population, people with schizophrenia have a higher suicide rate (about 5% overall) and more physical health problems, leading to an average decrease in life expectancy by 20 to 28 years. In 2015, an estimated 17,000 deaths were linked to schizophrenia. Source: Schizophrenia - Wikipedia

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