According to the World Health Organization, over 300 million people worldwide suffer from depression -- and treatments can be hit or miss. But two recent studies by Yale researchers have led to a new tool that may better personalize treatments for patients.
Finding the right treatment for chronic depression can be as complicated as the disorder, which often includes multiple symptoms treated with varying degrees of success.
Yale researchers wanted to know two things -- whether antidepressants work well on multiple symptoms of depression, and how effective medication is at keeping depression in remission.
Adam Chekroud, a doctoral student in the Yale Department of Psychology and lead author of the latest study, said they used data to identify three groups -- or clusters -- of symptoms experienced by patients.
"The first was a group of mood and emotional symptoms," Chekroud said. "These are things like anxiety or low mood. The second group was to do with sleep insomnia, and then the third group were what we called atypical symptoms. These are symptoms that are a bit less common --things like cognitive problems or having suicidal ideation."
Then they used statistical analysis to determine which antidepressants worked best for different sets of symptoms.
"It turns out that antidepressants in general were very effective at treating the mood or emotional symptoms," Checkroud said. "We also found differences between antidepressants as well. For sleep or insomnia symptoms, some antidepressants were effective. They would help patients sleep better at night and their depression would also recover in due course. But we found that antidepressants were not that effective in treating atypical symptoms."
Chekroud's team has built an online program with a database of specific symptoms. Doctors or patients can input their own information, and the program's algorithm can then produce a report which includes information about the severity of symptoms, medication recommendations, and likely side effects. They hope the program will allow doctors to optimize treatment options.
In a separate study, researchers looked at relapse and how effective antidepressants are at preventing future episodes of depression.
"I think the most striking finding from that study was that the protective effect of antidepressants was smaller than we expected," Chekroud said. "You might think that continuing to take antidepressants, everyone would reliably stay better -- and that was not the case."
In fact, Chekroud said, about a third of the patients relapsed even though they continued taking antidepressants, highlighting the need for additional strategies to help patients stay better. Chekroud points out that that strategy may involve more than antidepressants alone, such as psychotherapy or cognitive behavioral therapy.