Introduction: Fatigue and cognitive deficits are common symptoms affecting patients with multiple sclerosis.
Methods: The effects of interferon beta on fatigue and cognitive deficits were assessed in 50 patients with relapsing multiple sclerosis (recruited at a single center). The pre-treatment assessments were performed on visits 1 and 2 (Months 0 and 3). Patients started treatment with subcutaneous interferon beta-1a or beta-1b, or intramuscular interferon beta-1a at Month 3, with reassessment at visits 3 and 4 (6 and 12 months, respectively). Co-primary endpoints were change in fatigue (Modified Fatigue Impact Scale) and change in cognition (Brief Repeatable Battery of Neuropsychological Tests) from pre-treatment to visits 3 and 4. Follow-up data were obtained for 40 patients.
Results: The pre-treatment demographic and disease characteristics did not differ between groups. Improvements in fatigue levels were reported for patients receiving subcutaneous interferon beta-1a versus patients in the intramuscular interferon beta-1a group (p = .04) and in the interferon beta-1b group (p = .09). Improvements were also reported in five out of 17 cognitive indices for all the treatment groups.
Conclusion: The data suggest that interferon beta may reduce fatigue and cognitive deficits in patients with relapsing multiple sclerosis. Larger, randomized, and controlled studies are required to confirm our findings.