Recovery Michigan

How can you tell if someone is depressed? The Diagnostic and Statistical Manual of Mental Disorders (DSM) - the 'bible' of psychiatry - diagnoses depression when patients tick off a certain number of symptoms on the DSM checklist. A large-scale quantitative study coordinated at KU Leuven, Belgium, now shows that some 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.

To diagnose depression, psychiatrists typically tally up the number of depression symptoms that patients report in questionnaires. It does not matter which of the symptoms these patients have, as long as they have a certain number of them.

A new study challenges that approach. "We need to stop thinking of depression as a disease that causes a number of interchangeable symptoms", says lead author Dr Eiko Fried from the KU Leuven Faculty of Psychology and Educational Sciences. "Depression is a complex, extremely heterogeneous system of interacting symptoms. And some of these symptoms may be far more important than others".

In the study, the two main DSM symptoms - sad mood and decreased interest or pleasure - ranked among the top 5 in terms of centrality. But the researchers also found that DSM symptoms such as hypersomnia, agitation, and weight change are not more central than other common depression symptoms such as pessimism andanxiety.