Sep 30, 2014
Depression is the leading cause of disability in the world. It is a debilitating illness characterized by loss of energy, lack of pleasure in life and potentially suicidal thoughts. Diagnosis of this sickness is often done by family physicians, and is based on the patient’s reports of their symptoms. The problem with this system is that patients often under-report symptoms so diagnosis is difficult. Fortunately there may be another way.
A recent study in Nature published by Dr. EE Redei et al at Northwestern University in Chicago Illinois suggests that depression has biomarkers, or parameters that are measurable, in the blood stream. Before DNA gets translated into protein, it first gets converted into RNA transcripts. This is what they used for biomarkers—they extracted RNA from the blood of patients with and without Major Depressive Disorder and looked for differences. They found three markers that differed between those who were sick and those who were not.
Besides antidepressants, a common treatment for depression is cognitive behavioral therapy. Excitingly enough, they found transcript differences between those who improved from the therapy and those who did not. This indicates that the markers may be a measurable parameter of the severity of the illness. This means the blood test could be used to determine if treatment is working.
Having a blood test to diagnose depression is a huge step forward in the treatment of mental illness. If we could develop tests that catch these illnesses before they manifest themselves fully we could treat them before they get out of hand and the patients require hospitalization. This would keep healthcare costs down and improve the quality of life for many people.