If most of what we know about multiple sclerosis (MS) patients comes from patients who access MS- clinics, how much do we really know about MS patients? New research from Kyla McKay and Dr. Elaine Kingwell, part of the Pharmacoepidemiology in Multiple Sclerosis (PiMS) research team led by Dr. Helen Tremlett, evaluated population-level data on new cases of MS between 1996 and 2004. While they found that the majority (nearly 60 per cent) accessed an MS clinic in British Columbia, there were important differences between those who did and did not access an MS clinic.
The researchers found that only one per cent of the non-clinic cases had filled a prescription for an MS-specific disease-modifying therapy (DMT), compared to 51 per cent of the clinic cases. The reason for this is pretty straightforward, says McKay: “MS clinics were the only resource for DMT prescriptions under British Columbia’s reimbursement scheme. Basically, in order to have your DMT covered by the government, you had to receive a prescription from an MS-specialist neurologist at an MS clinic.”
“Getting one of these expensive drug treatments for MS is very challenging outside of an MS clinic,” says McKay.
People who did not visit MS clinics were still accessing health services, and the study findings were suggestive of a reliance on health care resources with greater frequency than those that came to an MS clinic.
“They were more likely to be hospitalized, and were seeing physicians with greater frequency than clinic users,” says McKay. “They also seem to have a higher burden of comorbidities, including chronic lung disease, hypertension, diabetes, migraine, and mood or anxiety disorders.”
Comorbidities such as these have been increasingly recognized as being detrimental in MS. They have been associated with a delayed MS diagnosis, a higher level of disability at diagnosis, and a lower quality of life.
“Comorbidities are common in MS, and our findings suggest that studies based on clinic cohorts may be underestimating the true rates of comorbidity in MS,” McKay says.
McKay, for her part, will continue looking at the role of psychiatric comorbidities related to MS disease progression as she completes the final year of her PhD research, which focuses on mental health in MS.
The study was funded by the Canadian Institutes of Health Research and the Rx&D Health Research Foundation (PI: Ruth Ann Marrie, University of Manitoba; co-PI Helen Tremlett, University of British Columbia). Dr Tremlett is the Canada Research Chair in Neuroepidemiology and Multiple Sclerosis.
The BC Ministry of Health, BC PharmaNet and BC Vital Statistics Agency approved access to the health administrative data which was facilitated by Population Data BC.
McKay KA, Tremlett H, Zhu F, Kastrukoff L, Marrie RA, Kingwell E. A population-based study comparing multiple sclerosis clinic users and non-users in British Columbia, Canada. Eur J Neurol. 2016 [Epub ahead of print]