May 27, 2015

MS Society-funded study brings to light importance of treating other medical conditions to improve health and survival


People who are affected by chronic diseases such as multiple sclerosis often encounter significant challenges given the long-lasting nature of the diseases and disability that is associated with them. It is important for health care professionals and researchers to better understand how the disease may impact one’s overall health over time and how complications can be managed to improve quality of life. It is also imperative to know how chronic diseases impact survival. For MS, studies suggest that people with MS are living longer now than they were before; however, their lifespans continue to be lower than that of people without MS who are the same sex and age. MS neurologist and senior researcher Dr. Ruth Ann Marrie from University of Manitoba set out to determine if co-morbidities (other conditions which arise in addition to MS) may be a contributing factor to the observed lowered survival among people with MS. Her study, funded by the MS Society of Canada, was published online in Neurology.

The Study

Dr. Marrie and colleagues reviewed health system data to gather information such as sex, age, medical claims and death records of Manitoban residents. They identified 5,797 people diagnosed with MS and 28,807 matched controls (people without MS who had similar characteristics to those with MS). They identified and evaluated the presence of co-morbidities among the MS and control groups, such as hypertension, diabetes, heart disease, lung disease, thyroid disease, epilepsy, migraine, depression, anxiety and bipolar disorder.


The researchers found that the life expectancy of people with MS has increased over time. The median survival age for the MS group was reported to be 76 years. This is slightly less than what was reported for the non-MS group which was 83 years. Data revealed that 44 percent of people with MS died from MS and MS-related complications, which is lower than previously reported. Deaths due to infection and lung diseases were more common in the MS group than the non-MS group.

The research team discovered that people with MS who had other co-existing conditions such as depression, anxiety, diabetes, heart disease, and chronic lung disease were at an increased risk of dying younger compared to people who only had MS; however, these conditions were also associated with a shorter lifespan in the non-MS group This means having other conditions did not affect the life expectancy of people with MS any more than it did for people without MS.

This study did not account for potential impact of the severity of MS or whether or not individuals were taking MS disease-modifying therapies.


Although differences in life expectancies of people with MS compared to people without MS have been reported, it is still important to note the study confirms previous evidence showing that people with MS are living longer. The observed association between life expectancy and presence of other conditions highlights a critical need to better understand and treat these conditions to enable people with MS to live an optimal quality of life and potentially improve survival.


Marrie RA et al. (2015). Effect of comorbidity on mortality in multiple sclerosis. Neurology. Epub ahead of print.