Etiology means the causes of a disease, and the etiology of schizophrenia, a serious form of mental illness, is not yet fully understood. People with schizophrenia generally have disordered thoughts, perceptions and ideas, causing then to lose touch with reality. It is thought that their brain chemistry may be altered so that messages do not pass between cells normally, and this could explain some of the symptoms. The etiology of schizophrenia could involve a number of factors acting together to cause such brain changes, with some being inherited, some environmental and some social. Known risk factors include having a relative with the disease, infections occurring during pregnancy, birth complications, stress and some illegal drugs.
Perceiving things that do not exist, believing impossible ideas, and experiencing abnormal ways of thinking constitute what are known as the positive symptoms of schizophrenia. These are symptoms which would not normally be found in most people, but they are positively present in schizophrenia. Negative symptoms of schizophrenia include the loss of normal traits found in most people, such as spontaneous movement, motivation, emotion and facial expression. It is not yet known why some symptoms are more prominent in one person than another. As schizophrenia seems to alter chemicals in the brain, current treatment is based on drugs known as antipsychotics, which restore brain chemistry as far as possible, but researchers hope to find better, possibly more preventive, treatments in the future.
Genetic factors implicated in the etiology of schizophrenia include having one or more relatives with the disease. For example, having two parents with schizophrenia could raise an individual's risk of developing the condition to around 40 percent. Having any first- or second-degree relatives with schizophrenia is also thought to increase one's risk. Older fathers may be more likely to produce children with schizophrenia.
Brain abnormalities associated with the etiology of schizophrenia can result from the abuse of drugs such as cocaine or amphetamines. Such drug use is linked to an increased risk of developing one of the schizophrenia subtypes called paranoid schizophrenia. Some brain changes may arise during pregnancy, possibly due to a viral illness or malnutrition, or during a complicated birth, where oxygen is deficient for a time.
The etiology of schizophrenia is complex and, when a number of other factors are already present, it is thought that psychological stress, in the form of hostile family interactions or social isolation, for example, may also make an individual more prone to developing the illness. Once a person has been diagnosed, the chances of a relapse can be minimized if family members are sympathetic and informed about coping strategies. A self-help group can also be beneficial in providing care and schizophrenia support.