Using the symptoms in the Diagnostic and Statistical Manual of Mental Disorders (DSM) alone in order to make a diagnosis of depression may not be the most accurate method, according to a new study.
Eiko Fried, PhD, of Catholic University Leuven, Belgium, and colleagues analyzed data on 28 symptoms reported by 3,463 patients with depression. The researchers then examined the relationships between the symptoms.
Some symptoms were found to be more connected than others, meaning that they carry a greater influence on the depressive process, according to the researchers.
The study found that the two main depression symptoms found in the DSM — sad mood and decreased interest or pleasure — were among the top five in terms of influence. But the researchers also noticed that depressive symptoms such as hypersomnia, agitation, and weight change are not more central to depression than other common symptoms such as pessimism and anxiety.
“We need to stop thinking of depression as a disease that causes a number of interchangeable symptoms,” Fried said in a statement. “Depression is a complex, extremely heterogeneous system of interacting symptoms. And some of these symptoms may be far more important than others.
“Ideally, the list of depression symptoms should become more comprehensive to do justice to the heterogeneity of depression,” he added.
To determine whether or not a patient suffers from depression, a doctor will often refer to a checklist of symptoms found in the Diagnostic and Statistical Manual of Mental Disorders (DSM), often called the “bible” of psychiatry. According to the current protocol, it does not matter which of the symptoms the patients have, as long as they have a certain number of them.
A new study shows that this may not be the most accurate way to diagnose depression, however, as some of these symptoms play a much bigger role than others in driving depression, and that the symptoms listed in DSM may not be the most useful ones.