Comorbid MS, Major Depressive Disorder Linked to Brain Volume Loss

Multiple Sclerosis
Multiple Sclerosis
Changes to brain structure indicate possible underlying connection to idiopathic major depressive disorder.

BARCELONA — Depression is one of the most common comorbidities in multiple sclerosis (MS), and now research indicates that it could have significant impact on cognitive impairment and hippocampal volume loss. The study was presented at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) Congress in Barcelona.

Nancy L. Sicotte, MD, of Cedars Sinai Medical Center in Los Angeles, and colleagues studied 105 subjects in order to contrast comorbid major depressive disorder (MDD) in MS with idiopathic MDD (iMDD). The subjects were divided into four cohorts: MS+MDD, MS-only, iMDD, and healthy controls. All subjects underwent structured clinical interview for psychiatric disorders and neuropsychological testing, and EDSS and MS Functional Composite scores were determined. 3T MRI scans were conducted for all participants, and brain volumes were obtained using the FIRST algorithm.

In the MS+MDD and MS-only groups, both right and left hippocampal volumes were significantly reduced (P< 0.01) compared to healthy controls. Hippocampal volume loss was most evident in the right hippocampus of the comorbid MS+MDD group. All patient groups had impaired verbal learning compared to healthy controls (ANCOVA P= 0.009), however those with iMDD were most impaired. Trends showed some patient group differences compared to healthy controls for delayed verbal memory (0.06) and processing speed (0.07).

Overall, comorbid MS and MDD was significantly linked to cognitive impairment and hippocampal volume loss. “These effects share features with, but are distinct from, idiopathic MDD suggesting that different pathophysiological underpinnings may exist between these forms of major depressive disorder,” the authors concluded.

For more coverage of ECTRIMS 2015, go here.

Reference

  1. Gold SM et al. Abstract 98. Presented at: The European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) Congress; Oct. 7-10, 2015; Barcelona.