Impacts of early-life adversity on microbiota and immune alterations in individuals with Major Depressive Disorder

The aim of this study is to determine if perturbations within the immune system and the gut microbiome are more pronounced in individuals with a history of childhood adversity and are aligned with the presence and severity of depressive symptoms.

Age range    

18-65 years old


Male and Female

Individuals are eligible if they

  • Have a primary diagnosis of Major Depressive Disorder;
  • Have the ability to give consent

Individuals are not eligible if they

  • Have a history of inflammatory bowel disease or of irritable bowel syndrome;
  • Are obese;
  • Have a history of cardiovascular diseases, diabetes, liver cirrhosis, or fatty liver disease;
  • Have a current alcohol or substance abuse/dependence;
  • Have used antibiotics, probiotics, or prebiotics in the month before collection of stool sample;
  • Have a known current bacterial, fungal, or viral infection;
  • Have a history of manic or hypomanic episode(s);
  • Have current psychosis.


The Royal's Institute of Mental Health Research, affiliated with the University of Ottawa
1145 Carling Ave, Ottawa, ON

Recruitment via

  • Self-Referral (by participant) – healthy control participants
  • Internal Referral – Major Depressive Disorder participants

Principal Investigator   

Marie-Claude Audet, PhD


Marie-Claude Audet
+1 (613) 722-6521 ext. 6849

*This study is actively recruiting participants