According to the Centers for Disease Control, postpartum depression in the US is between 11%-20%. Postpartum depression is a disorder that affects the mother’s ability to care for and bond with her new infant, as well as her functioning in day to day life. It can also produce long lasting consequences in children’s cognitive, social-emotional and physical health outcomes. The depression does not come alone though, it is associated with insomnia, fatigue, agitation, appetite problems, low self-esteem and anxiety. The anxiety often co-exists with the depression in postpartum states. If breast feeding is occurring, it is even more important to explore prevention strategies as many women will not take pharmaceuticals while breast feeding, they may have adverse effects on the breast fed infant, and It can take several weeks for the therapeutic effect of pharmaceutical antidepressants to occur.
The current study is a two-center randomized double-blind placebo-controlled trial testing the effect of Lactobacillus rhamnosus HN001 on atopic disorders including eczema, but also on pregnancy outcomes and postpartum symptoms of depression and anxiety. Pregnant women were randomized to receive either placebo or 1 billion colony forming units Lactobacillus rhamnosus HN001 daily, over a period of 6 months if breastfeeding. Mothers in the probiotic group reported significantly lower depression and anxiety scores than the placebo group.
Commentary: There is a growing body of literature linking the gut microbiota to brain chemistry and thus mood and behavior. The list of pathways involved in a bi-directional microbiome-gut-brain axis are multiple and many health problems, including mental-emotional disorders are associated with altered gastrointestinal function and alterations in gut microbial make up. The findings of the current study are consistent with two previous clinical studies of the effects of probiotics on mood. One was a randomized clinical trial in a population of 40 individuals with major depressive disorder treated with Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium bifidum or placebo, which found a significant reduction in symptoms of depression in the probiotic group. Another study in 39 individuals with chronic fatigue and anxiety were randomized to Lactobacillus casei or placebo and found a reduction in anxiety, but not in depression. Not all studies have demonstrated a significant therapeutic effect of probiotics on mood, but larger studies are being done to better understand this gut flora-brain connection and it will be interesting to watch this unfold and to better understand the possibilities for both prevention and treatment. In time, we will also better understand what might be the most effective choice of probiotic species and strains, duration and dose.
Reference: Slykerman R, Hood F, Wickens K, et al. Effect of Lactobacillus rhamnosus HN001 in pregnancy on postpartum symptoms of depression and anxiety: a randomised double-blind placebo-controlled trial. EBioMedicine 2017,https://doi.org/10,1016/j.ebiom.2017.09.013
