SUMMARY

• A team investigated health records and identified 2,312 people diagnosed with MS in two Canadian provinces.
• Over an average of more than 10 years, 36% of them developed mood or anxiety disorders.
• Over time women with depression were more likely to develop more severe disability.
• The researchers raise the possibility that treating psychiatric disorders in people with MS may reduce subsequent worsening of disability.

Background: Studies have suggested that psychiatric disorders are common in MS, and that people with MS experience bipolar disorder, anxiety and depression with a higher frequency than the general population. Having such a disorder along with MS can reduce a person’s quality of life, but it’s been unclear whether it can worsen the disease, which has been suggested for other chronic disorders. A team at the Canadian Institutes of Health Research and collaborators led by Dr. Ruth Ann Marrie (University of Manitoba) set out to investigate the frequency of psychiatric disorders in people with MS, and the possibility that having such disorders along with MS could worsen MS progression.

The Study: Using a combination of health record databases related to two Canadian provinces, the team looked at records of 2,312 people who had been diagnosed with multiple sclerosis. During a subsequent window averaging over 10 years, about 36% of the people met the criteria for having a mood or anxiety disorder. After adjusting for many factors, the team found that women, but not men, who had depression were significantly more likely to develop more severe MS disability (as measured by the standard EDSS scale of physical disability). Results involving men, and results related to anxiety and bipolar disorder were not statistically significant.

The researchers concluded that having psychiatric disorders may increase the eventual severity of disability in people with MS, raising the possibility that better management of those psychiatric disorders may reduce the severity of subsequent MS progression.