Subjective Report, Objective Neurocognitive Performance, and "Invisible Symptoms" in Multiple Sclerosis.

BACKGROUND: Self- and informant-report measures are often useful in predicting objective cognitive performance; however, the relationship between these reports and mood, anxiety, and fatigue requires further examination. Additionally, it remains unclear as to how these factors might be associated with objective neurocognitive performance. METHODS: Eighty-six persons with multiple sclerosis (PwMS; F = 65, M = 21) completed a comprehensive neuropsychological battery that included objective neurocognitive measures, subjective reports of neurocognitive function with the Multiple Sclerosis Neuropsychological Screening Questionnaire (MSNQ) Self-Report (MSNQ-S) and Informant-Report (MSNQ-I), and self-report measures of anxiety, depression, and fatigue. Hierarchical linear regressions were conducted with depression, anxiety, the interaction between depression and anxiety, cognitive fatigue, and physical fatigue as predictors. Outcome variables included the MSNQ-S, MSNQ-I, each of five neurocognitive composites, and global intraindividual variability (IIV). RESULTS: Although greater cognitive fatigue was associated with greater reported cognitive dysfunction, it was not associated with objective neurocognitive impairment. Greater depression predicted poorer performance on measures of processing speed and verbal memory, though the effects became non-significant once accounting for anxiety. The interaction between depression and anxiety predicted greater neurocognitive IIV; those with high levels of depression and anxiety demonstrated greater dispersion of scores. CONCLUSIONS: Cognitive fatigue may skew one's perception of their cognition, though it is not associated with objective impairment. However, co-occurring depression and anxiety were associated with greater variability which is a marker of poorer neurocognitive integrity. Our findings highlight the importance of accounting for depression, anxiety, and cognitive fatigue in PwMS, given that they are all potentially modifiable factors.

Relationship between subjective report and objective assessment of neurocognitive functioning in persons with multiple sclerosis.

OBJECTIVE: Persons with multiple sclerosis (PwMS) are at increased risk for cognitive dysfunction. Considering the impact and potential ramifications of cognitive dysfunction, it is important that cognition is routinely assessed in PwMS. Thus, it is also important to identify a screener that is accurate and sensitive to MS-related cognitive difficulties, which can inform decisions for more resource-intensive neuropsychological testing. However, research focused on available self-report screeners has been mixed, such as with the Multiple Sclerosis Neuropsychological Screening Questionnaire (MSNQ). This study aims to clarify the relationship between subjective and objective assessment of cognitive functioning in MS by examining domain-specific performance and intraindividual variability (IIV). METHODS: 87 PwMS (F = 65, M = 22) completed a comprehensive neuropsychological battery which included self- and informant-report measures of neurocognitive functioning. Scores were examined in relation to mean performance on five domains of cognitive functioning and two measures of IIV. RESULTS: The MSNQ-Self was inversely associated with executive function, verbal memory, and visual memory; it was not associated with IIV. The MSNQ-Informant was inversely associated with executive function and verbal memory, and positively associated with one measure of IIV. The MSNQ-Self showed a correlation of moderate effect size with depression (r = .39) while the MSNQ-Informant did not. CONCLUSIONS: Results suggest that the MSNQ-Self and MSNQ-Informant show similar utility. Our findings also suggest that domains of executive function and memory may be most salient, thus more reflected in subjective reports of cognitive functioning. Future work should further examine the impact of mood disturbance with cognitive performance and IIV.