Which ones hold water?
Reached for comment, Dean MacKinnon, MD, associate professor of psychiatry and behavioral sciences at Johns Hopkins University, Baltimore, noted that this analysis “extracts the vast amount of knowledge” gained from different studies on biomarkers in the CSF for depression.
“They were able to identify 97 papers that have enough information in them that they could sort of lump them together and see which ones still hold water. It’s always useful to be able to look at patterns in the research and see if you can find some consistent trends,” he told this news organization.
Dr. MacKinnon, who was not part of the research team, also noted that “nonreplicability” is a problem in psychiatry and psychology research, “so being able to show that at least some studies were sufficiently well done, to get a good result, and that they could be replicated in at least one other good study is useful information.”
When it comes to depression, Dr. MacKinnon said, “We just don’t know enough to really pin down a physiologic pathway to explain it. The fact that some people seem to have high cortisol and some people seem to have high permeability of blood-brain barrier, and others have abnormalities in dopamine, is interesting and suggests that depression is likely not a unitary disease with a single cause.”
He cautioned, however, that the findings don’t have immediate clinical implications for individual patients with depression.
“Theoretically, down the road, if you extrapolate from what they found, and if it’s truly the case that this research maps to something that could suggest a different clinical approach, you might be able to determine whether one patient might respond better to an SSRI or an SNRI or something like that,” Dr. MacKinnon said.
Dr. Benros reported grants from Lundbeck Foundation during the conduct of the study. Dr. MacKinnon has disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.