Fatigue in neurological disease: different patterns in stroke and multiple sclerosis.

Introduction. Fatigue is a complex, subjective experience, frequent in multiple sclerosis (MS) and stroke patients. The tiredness these patients experience can take on many features depending not only on the cerebral location of the lesions and mood aspects, but also on the pathophysiology of the disease. Thus, it is reasonable to expect that fatigue may have different implications in MS and stroke. The aim of the present work was to compare fatigue syndrome in these two populations. Patients were matched for handicap. Materials and Methods. Seventy-nine stroke and 39 MS outpatients were included with the following inclusion criteria: i) patients with possible or relapsing-remitting MS with an Expanded Disability Status Scale (EDSS) score < 2.5, disease duration < 6 years, and stable medical condition for at least 6 weeks; ii) stroke patients with mild neurological impairment, i.e. scoring < 3 at the National Institute of Health Stroke Scale (NIHSS) one year after stroke; iii) absence of functional impairment (Barthel index =100) and similar negligible handicap (Rankin scale < 2 for both groups); no or mild cognitive deficit; iv) neither DSMIV criteria of depression, nor significant anxious/depressive symptoms (Hospital Anxiety and Depression scale; HAD; score < 8) in both groups. The Fatigue Assessing Instrument (FAI) was used to assess fatigue. Results. Twenty-nine percent of stroke and 46 p. cent of MS patients had a significant score on the FAI (p < 0.05). Multiple regression analysis using groups, gender and age as factors showed a group effect in 3 out of 4 subscales: MS patients scored higher than stroke patients mainly for psychic impact (4.86 vs. 3.28), but also for severity (mean 3.86 vs. 2.97) and specificity (4.36 vs. 3.32). Response to rest (5.36 vs. 6.06) only tended to be better in the stroke group. In the subpopulation with significant fatigue scores, psychic impact was more elevated in the MS group. The functional consequence of fatigue in physical, professional and social activities were similar. Discussion. Fatigue was more severe in MS than stroke patients, independently of disability. The most significant factor in the MS group was the psychic impact, reflecting impaired motivation, concentration and irritability, despite the absence of depression. However, subjective consequences of fatigue on work, family and leisure activities were comparable in both groups.