Cognitive problems, both complaints and objective impairments, are frequent and disabling in patients with multiple sclerosis (MS) and profoundly affect daily living. However, intervention studies that focus on cognitive problems that patients experience in their daily lives are limited. This study therefore aimed to investigate the effectiveness of cognitive rehabilitation therapy (CRT) and mindfulness-based cognitive therapy (MBCT) on patient-reported cognitive complaints in MS.

In this randomized-controlled trial, MS patients with cognitive complaints completed questionnaires and underwent neuropsychological assessments at baseline, post-treatment and 6-month follow-up. Patient-reported cognitive complaints were primarily investigated. Secondary outcomes included personalized cognitive goals and objective cognitive function. CRT and MBCT were compared to enhanced treatment as usual (ETAU) using linear mixed models.

Patients were randomized into CRT (n=37), MBCT (n=36) or ETAU (n=37), of whom 100 completed the study. Both CRT and MBCT positively affected patient-reported cognitive complaints compared to ETAU at post-treatment (p<.05), but not 6 months later. At 6-month follow-up, CRT had a positive effect on personalized cognitive goals (p=.028) and MBCT on processing speed (p=.027). Patients with less cognitive complaints at baseline benefited more from CRT on the Cognitive Failures Questionnaire (i.e. primary outcome measuring cognitive complaints) at post-treatment (p=.012-.040), and those with better processing speed at baseline benefited more from MBCT (p=.016).

Both CRT and MBCT alleviated cognitive complaints in MS patients immediately after treatment completion, but these benefits did not persist. In the long term, CRT showed benefits on personalized cognitive goals and MBCT on processing speed. These results thereby provide insight in the specific contributions of available cognitive treatments for MS patients.