Stefanie Binzer, M.D., Ph.D., from the Karolinska Institutet in Stockholm, and colleagues conducted a retrospective study using linked data from three Swedish nationwide registries. Two incident cohorts were developed: Cohort 1 included all registered cases of MS in the MS Registry (2001 to 2014; 5,875 cases) with depression defined as one or more International Classification of Diseases-10th revision codes for depression, while cohort 2 included all MS cases in the MS registry (2005 to 2014; 3,817 cases) with depression defined as one or more prescriptions filled for an antidepressant.
The researchers found that in cohort 1, 8.5 percent of cases had depression, while in cohort 2, 33.8 percent of cases were prescribed an antidepressant. The risk for reaching sustained Expanded Disability Status Scale (EDSS) scores of 3.0, 4.0, and 6.0 was significantly higher among persons with depression (hazard ratios, 1.50, 1.79, and 1.89, respectively). Among persons exposed to antidepressants, the risk was similarly increased, with hazard ratios of 1.37, 1.93, and 1.86, respectively, for sustained EDSS scores of 3.0, 4.0, and 6.0.
“Future studies should examine whether effective treatment to reduce the burden of depression in MS has the potential to minimize MS disability,” the authors write.
Several authors disclosed financial ties to the pharmaceutical industry.