A study of the various scales of fatigue and impact on quality of life of patients with multiple sclerosis

Objectives. To explore fatigue in multiple sclerosis and evaluate the specificity of three fatigue scales in this condition: the fatigue severity scale, the specific fatigue scale and the fatigue impact scale. Material and methods. We sent out 60 questionnaires with the three scales and the quality of life scale, the Nottingham Health Profile, to patients with multiple sclerosis as clinically defined by Poser's criteria. Answers were received to 58 questionnaires and the data correlated by Sperman's correlation and the Student t test, with demographic variables (age, age of onset and sex) and clinical variables (clinical form, time the disease was present, period of time since the previous episode and Kurtzke scale (EDSS). Results. Fatigue was present in 78% of the patients. There was correlation between fatigue severity scale and EDSS, pyramidal function. cerebellar function, the period of time the illness was present and the clinical form. We found that the specific fatigue scale is independent of EDSS. The fatigue impact scale was correlated with the EDSS apart from the questions concerning cognitive function. Conclusions. Fatigue is a common symptom of multiple sclerosis which has an independent effect on cognitive function. It is also related to involvement of the pyramidal and cerebellar systems, and depends on the degree of disability and time the disease has been present. The specific fatigue scale is a good tool for exploration of this symptom of multiple sclerosis.