Dr. Helen Tremlett, Canada Research Chair in Neuroepidemiology and Multiple Sclerosis, and her research team have provided one of the most extensive assessments of the risk profile for the beta-interferons; a widely prescribed group of ‘disease-modifying’ drugs for people with relapsing-remitting multiple sclerosis (MS).
“Beta-interferons are generally thought of as having a favourable safety profile, especially compared to the newer therapies for MS. However, very few studies had comprehensively and quantitatively assessed their safety in clinical practice,” says Dr. Tremlett. “We looked at population-based health administrative and clinical data in British Columbia to determine safety outcomes, and to quantify risks associated with these commonly used drugs.”
The study, published in Neurology, presents novel information because no work so far has presented an extensive risk profile of the beta-interferons in the real-world setting.
“Some findings concur with what some others have found with these drugs,” says Dr. Tremlett. “For instance, we found elevated risks of migraine, depression, and haematological abnormalities. However, we also found that beta-interferon was associated with an elevated risk of stroke”
While there had been a few individual case reports of stroke associated with beta-interferon treatment for MS, until now, no study had confirmed or quantified this.
“We can see now, based on hospital, physician and pharmacy data from BC, that the beta-interferons are associated with a 1.8-fold increase risk of stroke, a 1.6-fold increase in the risk of migraine, and 1.3-fold increases in depression and haematological abnormalities” says Dr. Tremlett. “We still feel that overall, these drugs have an acceptable safety profile, but research like this enables healthcare professionals and patients to have a better insight into the risk-benefit profile of these medications.”
“It is important for patients with multiple sclerosis to have ongoing review of the benefits and risks of therapy, and to identify supportive strategies, such as diet and exercise, that could optimize their brain health” said Dr. Anthony Traboulsee, co-author on the study, associate professor of neurology and director of the MS Clinic at UBC.
The study was funded by the Canadian Institutes of Health Research (CIHR; grant MOP–93646; PI: Prof Tremlett) and the National Multiple Sclerosis Society (NMSS; grant RG 4202–A–2; PI: Prof Tremlett). Dr. Hilda de Jong is the first author and was funded by the Michael Smith Foundation for Health Research and the MS Society of Canada (Postdoctoral fellowships).