In summary, there is now strong evidence of partial overlap of genetic influences in schizophrenia and bipolar disorder, with a genetic correlation of around 0.6.Bipolar disorder and schizophrenia can be confused, but they are different chronic mental health disorders. Some of the symptoms may overlap. However, bipolar disorder mainly causes extreme mood swings, while schizophrenia causes delusions and hallucinations. After the onset of the disease, patients with both disorders appear to suffer a greater decline in cognitive function, but the magnitude of the decline is still greater in schizophrenia than in bipolar disorder.
Bipolar II disorder is diagnosed if the person has experienced at least one episode of major depression and at least one episode of hypomania (a milder form of mania). Shared polygenes with psychotic bipolar disorder influence liability to schizophrenia and predispose to the development of dopamine dysregulation following environmental stressors. The opposite position is that bipolar disorder and schizophrenia are separate disorders that cause the same general cognitive deficits (Bora et al. However, the extent to which bipolar disorder is considered separately from schizophrenia and other psychoses varies.
Therefore, the current pattern of results indicates that schizophrenia and bipolar disorders are not completely dichotomous entities, at least at the level of the neuroanatomical phenotype. A total of 350 coordinates (184 for bipolar disorder, 166 for schizophrenia) were extracted from the selected studies. Three decades of data from registries and hospitals (1973 to 200) involving 9 million Swedes from 2 million families were analyzed to determine the risk of schizophrenia and bipolar disorder among biological and non-biological relatives of patients with one or both disorders. Overall, we agree with the previous study by Ellison-Wright and Bullmore (20) that gray matter deficits identified in bipolar disorder are more restricted in extent compared to schizophrenia.
A further objective was to understand how the overall genetic risk of each disease is related to the presence of symptoms that a person with either disorder will have. If so, caudate head injuries can affect the motivational and learning abilities that are present in both schizophrenia and bipolar disorder. There were six significant ALE groups that indicated excess gray matter in bipolar disorder and schizophrenia. While a major depressive episode is not required for the diagnosis of bipolar disorder, depression often alternates with manic episodes and tends to occur more frequently than mania in many people.
In addition, what is lacking in the literature is an estimate of the extent to which brain regions involved in any of the disorders are more likely to be affected by schizophrenia or bipolar disorder. We found that in many regions the volume of gray matter was lower in both schizophrenia and bipolar disorder relative to neurotypical controls.
