Specific cognitive functions, such as nonverbal memory and attention/processing speed, are linked to specific mood profiles, such as anxiety and depression, in patients with multiple sclerosis (MS) according to a recent article published in the Multiple Sclerosis Journal.
A discovery and a replication cohort was utilized by researchers in this study. The discovery cohort, known as the Reserve Against Disability in Early Multiple Sclerosis (RADIEMS) cohort, included 185 patients recently diagnosed with MS. The replication cohort, known as the MEM CONNECT cohort, included 70 patients with relapsing-remitting MS. Each cohort completed a comprehensive neuropsychological tasks to assess cognition, and multiple surveys to assess anxiety and depression levels. The T2 lesion volume was also measured using magnetic resonance imaging in each patient to quantify the burden of disease.
Using correlation analysis of the cognitive assessment tasks, in addition to the anxiety and depression levels of the patients, researchers found in both cohorts lower anxiety levels were associated with better nonverbal memory (RADIEMS rp=–.220, P =.003; MEM CONNECT rp=–.271, P =.028). Further, lower depression levels were associated with increased attention/processing speed (RADIEMS rp=–.241, P =.001; MEM CONNECT rp=–.367, P =.002). No significant change was found when controlling for fatigue or T2 lesion volume. As per investigators, these results show “links of different mood profiles (anxiety, depression) to specific, objectively measured cognitive functions.”
Limitations of this study included its cross-sectional design, which prevents interpretation on the progression of cognitive decline in the context of changing anxiety and depression levels. In addition, the self-reporting measurement of mood symptoms may have limited the accuracy of findings as it pertains to anxiety and depression levels.
The researchers concluded that the consistency between the 2 cohorts evaluated establishes a step toward a more precise cognition-mood relationship model in patients with MS. They believe these findings support links of anxiety and depression to specific, objectively measured cognitive functions rather than linking them to worsening of mood to general or overall worsening of cognition. They that indicate further study in this area would be useful and that “[i]dentifying more precise cognitive phenotypes and considering interrelationships of cognition to mood has the potential to advance the field in our treatment approach for individuals with MS.”
Leavitt VM, Brandstadter R, Fabian M, et al. Dissociable cognitive patterns related to depression and anxiety in multiple sclerosis [published online June 24, 2019]. Mult Scler. doi: 10.1177/1352458519860319