As mental illnesses are diagnosed based on symptoms and clinical interviews, there's room for misdiagnoses, Newsweek writes. It adds, though, that there's growing evidence that certain biomarkers of mental illnesses can be uncovered in patients' blood.
For instance, Cambridge University's Sabine Bahn has found that people with schizophrenia appear to also have differences in how they manage glucose — even before being treated for the disease. This, she tells Newsweek, could be used as a blood test to spot schizophrenia in its early stages, and she and her colleagues have developed a panel of biomarkers to do just that. Other researchers have likewise found biomarkers that could distinguish people with bipolar disorder from those with depression, a common misdiagnosis that people with bipolar disorder receive.
However, Newsweek notes that such tests haven't yet made their way into clinical practice, but their developers hope they'll become part of standard testing panels. "Psychiatric disorders often present with other diseases such as diabetes and some immune disorders," Bahn says. When patients seek treatment for those illnesses, then perhaps the panels could pick up the psychiatric condition as well.