Some estimates suggest that 14.7 to 18.5 percent of people with major depression may experience psychotic features and that the prevalence rates may rise with age. This form of depression is an underdiagnosed and undertreated condition.
Some people who have severe depression may also experience hallucinations and delusional thinking, the symptoms of psychosis. Depression with psychosis is known as psychotic depression.
Prevalence of Depression in the Life Course of Schizophrenia
The prevalence of depressive disorder in schizophrenia has been reported to be around 40%, however the stage of illness (early vs chronic) and state (acute or post-psychotic) factors influences figures, which can thus vary considerably.
Epidemiological research suggests that 15–19% of patients with major depression exhibit hallucinations and/or delusions.
Although psychotic depression itself cannot evolve into schizophrenia, when severe depression is untreated or undertreated, it's possible for the resulting distress and side effects to trigger an underlying psychotic disorder, such as schizoaffective disorder.
People who have psychotic episodes are often totally unaware their behaviour is in any way strange or that their delusions or hallucinations are not real. They may recognise delusional or bizarre behaviour in others, but lack the self-awareness to recognise it in themselves.
Schizophrenia affects approximately 24 million people or 1 in 300 people (0.32%) worldwide. This rate is 1 in 222 people (0.45%) among adults (2).
Someone experiencing mania will typically have upbeat hallucinations or delusions, while a person in a depressive state will have negative delusions. Because schizophrenia is not a mood disorder, a person with schizophrenia may not necessarily experience hallucinations and delusions that correlate with his or her mood.
Psychosis may be a symptom of a mental illness, such as schizophrenia, bipolar disorder, or severe depression. However, a person can experience psychosis and never be diagnosed with schizophrenia or any other disorder.
Schizophrenia and Other Psychoses
Psychoses, including schizophrenia, is a severe mental illness impacting about 23 million people worldwide and is characterized by distortions in thinking, perception, emotions, sense of self, and behavior.
The most common psychotic disorder is schizophrenia. This illness causes behavior changes, delusions and hallucinations that last longer than six months and affect social interaction, school and work.
The types of delusions and hallucinations are often related to your depressed feelings. For example, some people may hear voices criticizing them, or telling them that they don't deserve to live. The person may develop false beliefs about their body, such as believing that they have cancer.
Medications often used to treat depression or ADD can certainly cause manic episodes, including severe manic episodes with psychotic symptoms like hallucinations or delusions. Those episodes can come on quite suddenly.
Non-psychotic disorders, which used to be called neuroses, include depressive disorders and anxiety disorders like phobias, panic attacks, and obsessive-compulsive disorder (OCD).
What are the early signs of schizophrenia? The most common early signs of schizophrenia may include social withdrawal, depression, hostility, oversleeping or insomnia, inability to cry or express joy, and deterioration of personal hygiene. The early stage of the schizophrenia is called 'the prodromal phase'.
The fundamental symptoms, which are virtually present through all the course of the disorder (7), are also known as the famous Bleuler's four A's: Alogia, Autism, Ambivalence, and Affect blunting (8). Delusion is regarded as one of the accessory symptoms because it is episodic in the course of schizophrenia.
In this early phase of schizophrenia, you may seem eccentric, unmotivated, emotionless, and reclusive to others. You may start to isolate yourself, begin neglecting your appearance, say peculiar things, and show a general indifference to life.
Schizophrenia is typically diagnosed in the late teens years to early thirties, and tends to emerge earlier in males (late adolescence – early twenties) than females (early twenties – early thirties). More subtle changes in cognition and social relationships may precede the actual diagnosis, often by years.
In most people with schizophrenia, symptoms generally start in the mid- to late 20s, though it can start later, up to the mid-30s. Schizophrenia is considered early onset when it starts before the age of 18. Onset of schizophrenia in children younger than age 13 is extremely rare.
Risk factors
Having a family history of schizophrenia. Some pregnancy and birth complications, such as malnutrition or exposure to toxins or viruses that may impact brain development. Taking mind-altering (psychoactive or psychotropic) drugs during teen years and young adulthood.
Typically, a psychotic break indicates the first onset of psychotic symptoms for a person or the sudden onset of psychotic symptoms after a period of remission. Symptoms may include delusional thoughts and beliefs, auditory and visual hallucinations, and paranoia.