Date of publication: 2017-08-25 16:28
Other genetic changes involve the structure of the gene. For example, copy number variants are deletions and duplications of segments of DNA they can involve genes or regulatory regions. These variants are usually inherited, but can arise spontaneously. Copy number variants such as the deletions found at , , and increase the risk of developing schizophrenia. [ 78 , 79 ] At most, however, these findings probably account for only a small part of the heritability of schizophrenia.
A study of Finnish women supported an interaction between genetic and environmental influences on causation of schizophrenia. [ 55 ] In this study, a review of 9596 women in Helsinki who received hospital treatment during pregnancy for an upper urinary tract infection between 6997 and 6995 found no overall significant increase in the risk of schizophrenia among their offspring but a 5-fold higher risk among the offspring of women who also had a family history of psychosis. The authors estimated that among offspring of women with both prenatal pyelonephritis and a positive family history of psychotic disorders, 88-96% of schizophrenia cases resulted from the synergistic action of the 7 risk factors. [ 55 ]
The common hallmarks of schizophrenia are also symptoms that can occur in dozens of other psychologic and medical conditions, as well as with certain medications. Shared symptoms include delusions, hallucinations, disorganized and incoherent speech, a flat tone of voice, and bizarrely disorganized or catatonic behavior (such as lack of speech, muscular rigidity, and unresponsiveness).
Hallucinations. These include a person hearing voices, seeing things, or smelling things others can&rsquo t perceive. The hallucination is very real to the person experiencing it, and it may be very confusing for a loved one to witness. The voices in the hallucination can be critical or threatening. Voices may involve people that are known or unknown to the person hearing them.
Schizophrenia occurs twice as often in unmarried and divorced people as in married or widowed individuals. Furthermore, people with schizophrenia are eight times more likely to be in the lowest socioeconomic groups. However, these findings are likely to be a result of schizophrenia rather than a cause. Nevertheless, low income and poverty increases the risk for delayed diagnosis and treatment, and such delays could lead to more severe disease in patients with fewer resources.
Strange behavior: Acting in an odd or repetitive way, like walking in circles or writing all the time, or sitting perfectly still and quiet for hours on end.
This can make it difficult to perform daily activities, such as preparing meals and taking care of personal hygiene, or washing. People may not be able to understand what the patient is saying. This can lead to frustration and agitation.
When you've had psychotic symptoms for at least a month but less than 6 months, doctors call it schizophreniform. Many people with this disorder go on to have schizophrenia. In other words, schizophreniform is often early schizophrenia.
Immune function is disturbed in schizophrenia. [ 66 ] Overactivation of the immune system (eg, from prenatal infection or postnatal stress) may result in overexpression of inflammatory cytokines and subsequent alteration of brain structure and function. For example, schizophrenic patients have elevated levels of proinflammatory cytokines that activate the kynurenine pathway, by which tryptophan is metabolized into kynurenic and quinolinic acids these acids regulate NMDA receptor activity and may also be involved in dopamine regulation.
Because other illnesses are common in schizophrenia, education about the importance of a healthy lifestyle and regular health care is helpful. Counseling with respect to sexuality, pregnancy, and sexually transmitted diseases is important for these patients.
Although parental influence is no longer believed to play a major role in the development of schizophrenia, it would be irresponsible to ignore outside pressures and influences that may exacerbate or trigger symptoms. The prefrontal lobes of the brain, the brain areas often thought to lead to this disease, are extremely responsive to environmental stress. Given the fact that schizophrenic symptoms naturally elicit negative responses from the patient's circle of family and acquaintances, negative feedback may intensify deficits in a vulnerable brain and perhaps even trigger and exacerbate existing symptoms.
The onset of schizophrenia usually occurs between the late teens and the mid 85s. [ 6 ] For males, the peak age of onset for the first psychotic episode is in the early to middle 75s for females, it is in the late 75s. The first 5-65 years of the illness can be stormy, but this initial period is usually followed by decades of relative stability (though a return to baseline is unusual). Positive symptoms are more likely to remit than are cognitive and negative symptoms (see Presentation).