A subset of bipolar disorder is strongly linked to inflammation, and a treatable immune system condition could be mistaken for bipolar disorder or schizophrenia.
Researchers at the Houston Methodist Neurological Institute believe that many people diagnosed with bipolar disorder or schizophrenia actually have a form of encephalitis that interferes with brain receptors. This autoimmune disease is called anti-NMDA receptor encephalitis.
In this condition the body’s own anti-bodies attack the brain and produce symptoms impacting decision making ability and a person’s sense of perception that are the same symptoms found in people with serious mental illness.
The research is ongoing and is significant because the condition is completely reversible with existing immune deficiency therapies.
Other published research indicates high rates of inflammatory medical comorbidities in some patients with bipolar disorder.
Researchers believe that autoimmune disorders or chronic infections, such as inflammatory bowel disease, autoimmune thyroiditis or herpes simplex virus, that cause significant inflammation may be implicated in the severity of bipolar disorder, if not outright causing bipolar-like symptoms, in a subset of patients diagnosed with BD.
However, as yet the researchers have not defined that subset, nor have they been able to definitively distinguish between patients with BD related to autoimmune disease and patients with more typical bipolar disorder.
The report points out that, “The association between BD and inflammatory comorbidities has been well established in numerous epidemiological studies; however, the direction of causality remains somewhat unclear.”
This means that autoimmune disease related inflammation may be causing the bipolar disorder, or BD may be causing the inflammation. Epidemiological studies indicate that immune dysfunction, inflammatory disease and bipolar disorder are comorbid and perpetuate each other.
This is why medical research is so hard.
Preliminary research into the impact of anti-inflammatory drugs on BD reveals that such medicines can be quite effective at treating bipolar disorder depression. The success of these drugs against mania is less certain.
Studies also indicate that the co-occurrence of inflammatory autoimmune disease and BD may be one of the explanations for the early mortality rates found in people with BD.
I’ve lived with bipolar disorder for many years and have always held out hope that some easy to treat physical condition would be discovered to be the cause of BD. Then I could receive the treatment, get over bipolar disorder, and get on with a normal life.
While encouraging, this research illustrates how much work still needs to be done before a link between autoimmune disease and BD is accepted by the wider psychiatric community. If that link is confirmed, it is still notable that inflammation is only implicated in some bipolar patients, not in all that were studied.
Still, it’s encouraging to see this work being done. As the NIH report indicates, autoimmune inflammation research is a frontier in medicine, and inflammation pops up as an underlying condition in many medical diagnoses.
Bipolar disorder appears to be one of these conditions. If nothing else, while causation may not be found, this research may make bipolar disorder easier to treat.