Schizophrenia

Schizophrenia is a mental disorder[17] characterized by reoccurring episodes of psychosis that are correlated with a general misperception of reality.[7] Other common signs include hallucinations (typically hearing voices), delusions (i.e., paranoia), disorganized thinking and behavior,[10] social withdrawal, and flat affect.[7] Symptoms develop gradually and typically begin during young adulthood and are never resolved.[3][10] There is no objective diagnostic test; diagnosis is based on observed behavior, a psychiatric history that includes the person's reported experiences, and reports of others familiar with the person.[10] For a diagnosis of schizophrenia, the described symptoms need to have been present for at least six months (according to the DSM-5) or one month (according to the ICD-11).[10][18] Many people with schizophrenia have other mental disorders, especially substance use disorders, depressive disorders, anxiety disorders, and obsessive–compulsive disorder.[10]
About 0.3% to 0.7% of people are diagnosed with schizophrenia during their lifetime.[19] In 2017, there were an estimated 1.1 million new cases and in 2022 a total of 24 million cases globally.[2][20] Males are more often affected and on average have an earlier onset than females.[2] The causes of schizophrenia may include genetic and environmental factors.[7] Genetic factors include a variety of common and rare genetic variants.[21] Possible environmental factors include being raised in a city, childhood adversity, cannabis use during adolescence, infections, the age of a person's mother or father, and poor nutrition during pregnancy.[7][22]
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.[10][23] The other half will have a lifelong impairment.[24] In severe cases, people may be admitted to hospitals.[23] Social problems such as long-term unemployment, poverty, homelessness, exploitation and victimization are commonly correlated with schizophrenia.[25][26] Compared to the general population, people with schizophrenia have a higher suicide rate (about 5% overall) and more physical health problems,[27][28] leading to an average decrease in life expectancy by 20[13] to 28 years.[14] In 2015, an estimated 17,000 deaths were linked to schizophrenia.[16]
The mainstay of treatment is antipsychotic medication, including olanzapine and risperidone, along with counseling, job training and social rehabilitation.[7] Up to a third of people do not respond to initial antipsychotics, in which case clozapine gained approval by the US Food and Drug Administration for treatment-resistant cases.[29] In a network comparative meta-analysis of 15 antipsychotic drugs, clozapine was significantly more effective than all other drugs, although clozapine's heavily multimodal action may cause more significant side effects.[30] In situations where doctors judge that there is a risk of harm to self or others, they may impose short involuntary hospitalization.[31] Long-term hospitalization is used on a small number of people with severe schizophrenia.[32] In some countries where supportive services are limited or unavailable, long-term hospital stays are more common.[33]