Researcher developing precise ways of selecting and dosing drug therapies

The use of psychotropic medications to treat mental health disorders such as depression and schizophrenia and neurodevelopmental disorders like ADHD in children and adolescents is relatively common, with almost four per cent of children and 13.5 per cent of adolescents being on a medication, according to this study.  

There are numerous medications available to treat these conditions, but understanding what treatment will best suit a particular individual often comes down to trial and error. In fact, up to half of children prescribed medications for mental health won’t respond or will experience burdensome adverse drug reactions. 

Dr. Chad Bousman, PhD, an associate professor in the Dept. of Medical Genetics and the Institute’s newest member, is hoping to develop precise ways of selecting and dosing drug therapies for individual patients. 

His lab, the Psychiatric Pharmocogenomics (PsychPGx) lab, discovers, develops and evaluates genomic-based tools capable of guiding decision-making and improving mental health outcomes. Although his primary focus is on optimizing selection and dosing of drug therapies used to treat depression and schizophrenia, he is also involved in research examining the interactive effect genes and environments have on the brains of those with mental health problems. 

His flagship project, PGx-SParK, the first of its kind in Canada, has enrolled more than 1,500 youth ages six to 24 in Western Canada who are starting or changing medication. The program provides free pharmacogenetic testing, a specific type of genetic testing that has the potential to improve drug efficacy and reduce the morbidity, mortality and cost associated with adverse drug reactions. 

Bousman has several other projects underway, such as one looking at optimizing antidepressant prescribing in adolescents; one identifying genomic markers associated with psychostimulant response and side effects in youth with ADHD; and another international study investigating potential genomic markers that could be used to identify patients at highest risk of developing cardiac side effects associated with clozapine therapy, an antipsychotic drug. 

“The ultimate goal is to advance precision prescribing to reduce some of the uncertainty for physicians, patients and their caregivers,” says Bousman, noting his work helped support the development of international guidelines for antidepressants in youth. 

Bousman’s academic journey started at the University of Wisconsin, where he earned his undergrad in Community Health Sciences. He completed his masters of public health at San Diego State University and his PhD at the University of California, San Diego. During his PhD work, he focused on genetic epidemiology. 

Bousman began his postdoctoral work in Melbourne, Australia trying to find biomarkers for diagnoses of psychiatric disorders. It was during this time that he questioned the trajectory of his work. 

“There was a lightbulb moment for me when a psychiatrist told me they weren’t likely to order a genetic test to diagnose schizophrenia because the condition isn’t difficult to determine,” says Bousman. “I learned the problem isn’t about the diagnosis but what drug will work with individual patients.” 

The discovery changed Bousman’s focus to the genetics of medications, a new field of research at the time. 

“Research in youth mental health, in particular, has been neglected,” he says. “And you can make a huge difference in the lives of young people. You can change their developmental trajectories.” 

In addition to his work in psychiatric medications, Bousman is involved in cross-discipline collaborative work, such as a project looking at optimizing stroke medication in conjunction with Dr. Micheal Hill, MD.  He is open to collaboration with other researchers looking at cardiovascular and autonomic conditions like syncope and heart disease. 

“Pharmacogenetic testing is an interdisciplinary area, and I think it could be of value to others,” says Bousman. “I am open to expanding my research.” 

Dr. Chad Bousman is also a member of the Alberta Children’s Health Research Institute and the Hotchkiss Brain Institute.