Objective: To investigate the effect of fatigue and depression on disease progression in multiple sclerosis (MS), and the long-term prognosis of these symptoms.
Methods: 228 patients with MS were investigated for fatigue and depression with the Fatigue Severity Scale (FSS) and Center for Epidemiologic Studies Depression Scale (CES-D). These patients regularly attended the MS clinic, where disability scores and the development of secondary progression were monitored. After 10 years, the 149 patients remaining from the original cohort were asked to participate in a repeat assessment of fatigue and depression and 96 (64%) could be re-evaluated. In relapsing-remitting patients, the influence of baseline fatigue and depression on the risk of secondary progression during the following 10 years was assessed with survival analyses. In the whole patient group, we investigated the influence of baseline fatigue and depression on progression of disability at 10 years. We also investigated differences in fatigue, depression and disability scores between baseline and 10 years.
Results: Fatigue and depression at baseline did not predict the development of secondary progression or progression of disability. Most patients who were fatigued or depressed at baseline remained so at 10 years, and the majority of patients not experiencing these symptoms remained free of them. FSS and CES-D scores were not significantly different between baseline and 10 years, while disability scores significantly increased.
Conclusion: Our data suggest that fatigue and depression in MS are unrelated to disease progression in MS. Fatigue and depression tend to persist at roughly the same levels over time.