Blood Markers Can Predict Depression in Pregnancy

Summary: Researchers identified 15 biomarkers in blood samples that predict the risk of developing depression during pregnancy with 83% accuracy.

Source: Van Andel Research Institute

Signs of inflammation in the blood reliably predict and identify severe depression in pregnancy, reports a new study led by scientists at Van Andel Institute and Pine Rest Christian Mental Health Services.

The team’s analysis established a set of 15 biological markers found in the blood that can predict if pregnant women will experience significant depressive symptoms with 83% accuracy.

The findings could give physicians a much-needed tool to identify women who may be at risk for depression and better tailor their care throughout pregnancy.

Nearly one in five new mothers experience severe depression during or after pregnancy and an estimated 14% have suicidal thoughts. Inflammation can lead to worsening depressive symptoms, and pregnancy is a major inflammatory event.

“Depression isn’t just something that happens in the brain—its fingerprints are everywhere in the body, including in our blood,” said Lena Brundin, M.D., Ph.D., a VAI professor and co-senior author of the study.

“The ability to predict pregnancy-related depression and its severity will be a gamechanger for protecting the health of mothers and their infants. Our findings are an important leap forward toward this goal.”

The study, published today in Translational Psychiatry, is among the first of its kind and followed 114 volunteers from Spectrum Health’s Obstetrics and Gynecology Clinics throughout their pregnancies. Participants provided blood samples and underwent clinical evaluations for depressive symptoms in each trimester and the postpartum period.

“Having an objective and easily accessible method associated with depression risk, such as a blood test, provides a unique tool for helping identify women who may develop depression during pregnancy,” said Eric Achtyes, M.D., M.S., staff psychiatrist at Pine Rest, an associate professor at Michigan State University and co-senior author of the study.

“Our findings are an exciting development and an important first step toward using these types of methods more widely to help patients. Our next steps include replicating the results in additional patient samples to verify cut-offs for depression risk.”

Abstract

Cytokines and tryptophan metabolites can predict depressive symptoms in pregnancy

Depression during and after pregnancy affects up to 20% of pregnant women, but the biological underpinnings remain incompletely understood. As pregnancy progresses, the immune system changes to facilitate fetal development, leading to distinct fluctuations in the production of pro-inflammatory factors and neuroactive tryptophan metabolites throughout the peripartum period.

Therefore, it is possible that depression in pregnancy could constitute a specific type of inflammation-induced depression. Both inflammatory factors and kynurenine metabolites impact neuroinflammation and glutamatergic neurotransmission and can therefore affect mood and behavior. To determine whether cytokines and kynurenine metabolites can predict the development of depression in pregnancy, we analyzed blood samples and clinical symptoms in 114 women during each trimester and the postpartum.

We analyzed plasma IL-1β, IL-2, -6, -8, -10, TNF, kynurenine, tryptophan, serotonin, kynurenic- quinolinic- and picolinic acids and used mixed-effects models to assess the association between biomarkers and depression severity. IL-1β and IL-6 levels associated positively with severity of depressive symptoms across pregnancy and the postpartum, and that the odds of experiencing significant depressive symptoms increased by >30% per median absolute deviation for both IL-1β and IL-6 (both P = 0.01). A combination of cytokines and kynurenine metabolites in the 2nd trimester had a >99% probability of accurately predicting 3rd trimester depression, with an ROC AUC > 0.8.

Altogether, our work shows that cytokines and tryptophan metabolites can predict depression during pregnancy and could be useful as clinical markers of risk. Moreover, inflammation and kynurenine pathway enzymes should be considered possible therapeutic targets in peripartum depression.