Unmasking the invisible: Correlates and impact of cognitive complaints in MS

BACKGROUND: Patient-reported outcome measures (PROMs) are increasingly used in multiple sclerosis (MS) to capture subjective aspects of disease burden. However, the relationship between perceived cognitive deficits, objective cognitive impairment, psychological symptoms, and functional outcomes remains unclear. METHODS: We conducted a cross-sectional study on 263 people with MS. Objective cognition was assessed using the Brief International Cognitive Assessment for MS (BICAMS). Subjective cognitive complaints were derived from selected items of the Modified Fatigue Impact Scale, while independence was evaluated using items from the Multiple Sclerosis Impact Scale-29. Mood was assessed with the Hospital Anxiety and Depression Scale. Multivariable regression models were applied. RESULTS: Objective cognitive impairment was detected in 15.2% of patients, whereas 76.8% reported subjective cognitive difficulties. Subjective complaints were not independently associated with objective cognitive performance. Depressive symptoms emerged as the only significant predictor of perceived slowed thinking and concentration difficulties. Physical disability (EDSS) was the sole independent predictor of both dependence on others and limited independence. These findings were consistent across disability subgroups. CONCLUSIONS: Subjective cognitive complaints in MS appear to be more closely related to psychological factors than to objective cognitive impairment, while functional autonomy is primarily driven by physical disability. These results highlight the importance of integrating psychological assessment into routine clinical evaluation to better address patients' perceived cognitive difficulties and overall quality of life.