More work remains
Although the study is thought to be the largest to date to examine lipid profiles associated with serious psychiatric illness, much work remains, Dr. Schulze noted.
“At this time, based on these first results, no clinical diagnostic test can be derived from these results,” he said.
He added that the development of reliable biomarkers based on lipidomic profiles would require large prospective randomized trials, complemented by observational studies assessing full lipidomic profiles across the lifespan.
Researchers also need to better understand the exact mechanism by which lipid alterations are associated with schizophrenia and other illnesses.
Physiologically, the investigated lipids have many additional functions, such as determining cell membrane structure and fluidity or cell-to-cell messaging.
Dr. Schulte noted that several lipid species may be involved in determining mechanisms important to synaptic function, such as cell membrane fluidity and vesicle release.
“As is commonly known, alterations in synaptic function underly many severe psychiatric disorders,” she said. “Changes in lipid species could theoretically be related to these synaptic alterations.”
A better marker needed
In a comment, Stephen Strakowski, MD, professor and vice chair of research in the department of psychiatry, Indiana University, Indianapolis and Evansville, noted that while the findings are interesting, they don’t really offer the kind of information clinicians who treat patients with serious mental illness need most.
Dr. Stephen Strakowski
“Do we need a marker to tell us if someone’s got a major mental illness compared to a healthy person?” asked Dr. Strakowski, who was not part of the study. “The answer to that is no. We already know how to do that.”
A truly useful marker would help clinicians differentiate between schizophrenia, bipolar disorder, major depression, or another serious mental illness, he said.
“That’s the marker that would be most helpful,” he added. “This can’t address that, but perhaps it could be a step to start designing a test for that.”
Dr. Strakowksi noted that the findings do not clarify whether the lipid profile found in patients with schizophrenia predates diagnosis or whether it is a result of the mental illness, an unrelated illness, or another factor that could be critical in treating patients.
However, he was quick to point out the limitations don’t diminish the importance of the study.
“It’s a large dataset that’s cross-national, cross-diagnostic that says there appears to be a signal here that there’s something about lipid profiles that may be independent of treatment that could be worth understanding,” Dr. Strakowksi said.
“It allows us to think about developing different models based on lipid profiles, and that’s important,” he added.
The study was funded by the National Key R&D Program of China, National One Thousand Foreign Experts Plan, Moscow Center for Innovative Technologies in Healthcare, European Union’s Horizon 2020 Research and Innovation Programme, NARSAD Young Investigator Grant, German Research Foundation, German Ministry for Education and Research, the Dr. Lisa Oehler Foundation, and the Munich Clinician Scientist Program. Dr. Schulze and Dr. Schulte reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.