The months following birth can be challenging for mothers experiencing postpartum depression (PPD). Cognitive behavioural therapy (CBT) is usually a successful PPD intervention, says Brock researcher John Krzeczkowski (BSc ’15), who is leading a team to find out how and why it works.

Krzeczkowski says PPD affects one in five mothers and has negative effects on a child’s ability to regulate their feelings and behaviours.

The Assistant Professor of Health Sciences and his team are investigating whether epigenetics, or how behaviour and environment change the way the body reads DNA, play a role in CBT’s success.

“We know that significant modifications in an individual’s environment can lead to changes that turn on and turn off certain genes,” says Krzeczkowski. “We want to know whether we can detect these changes in those receiving treatment for postpartum depression.”

A form of psychotherapy, CBT seeks to change the thoughts, attitudes and beliefs of people experiencing difficult situations, such as PPD.

Krzeczkowski’s team aims to determine whether patterns of DNA methylation, an epigenetic modification that affects gene expression, change in four genes that strongly predict parental mood and behaviours following CBT treatment.

The study will include 172 mothers and their babies. Half of the mothers will undergo nine weeks of online CBT and half will receive treatment as usual, which includes regularly scheduled visits with primary care physicians, along with other interventions chosen by the mothers.

The mothers’ DNA will be analyzed using saliva samples collected during the process and their depression and parenting behaviours will be rated using standardized scales. The infants’ saliva will also be collected and analyzed to see whether their genes are affected by mother-child bonding.

“Biological evidence showing cognitive behavioural therapy is effective could make it more likely for mothers with postpartum depression to seek out these treatments,” says Krzeczkowski. “The results could also lead to tools to identify individuals that may best respond to this therapy, leading to enhanced outcomes in Canada and around the world.”

Krzeczkowski’s research team includes Patrick McGowan, Professor of Biology at the University of Toronto; Ryan Van Lieshout, Associate Professor of Psychiatry and Behavioural Neurosciences at McMaster University; Maria Ospina, Professor of Public Health and Epidemiology at Queen’s University; and Allison Flynn-Bowman (MA ‘19), Graduate Liaison and Support Coordinator in Brock’s Faculty of Social Sciences and Community Manager at the Life with a Baby Foundation.

The team’s work is supported by a one-year $146,000 Biomedical Discovery Grant from the Canadian Institutes of Health Research (CIHR) under the National Women’s Health Research Initiative. Co-led by CIHR, the federal government initiative aims to advance a coordinated research program that addresses under-researched and high-priority areas of women’s health.

“This research has the potential to impact women and families across the country and that’s why it is so important that the Government of Canada supports this research with funding,” says Vance Badawey, Member of Parliament for Niagara Centre.

“Research that increases our knowledge of the impacts of mental health and how to treat it is critically important,” says Chris Bittle, Member of Parliament for St. Catharines.

Krzeczkowski’s current study is building on earlier research on postpartum depression, also being funded by a CIHR Project Grant.

Results of that study, which began in 2021, show treating postpartum depression with CBT leads to beneficial changes in infant brain development, mother-infant interactions and infant temperament behavior, says Krzeczkowski.

“The next stage of this research is to more fully explain how changes in mothers are not only leading to better outcomes in their lives, but are translating to their infants as well,” he says.