Fatigue in multiple sclerosis is a diagnostic challenge: A cross-sectional study

Introduction: Multiple sclerosis (MS) is a chronic and unpredictable demyelinating disease of the central nervous system (CNS). While MS is mostly known for muscle weakness, numbness, and pain, but fatigue is the most common complaint of this condition. Despite this fact, MS related fatigue is one of the most misunderstood symptoms. Methods: A non-interventional study of 100 individuals was conducted in the MS clinic, Tabriz University of Medical Sciences. Patients were divided into groups with and without complaints of fatigue. The course of the disease was determined for all patients. To quantify fatigue, the Modified Fatigue Impact Scale (MFIS) was used. Furthermore, mood disorders, pain, disability, nocturia, insomnia, and spasticity were evaluated among the patients. Results: Overall, fatigue was diagnosed in 61 through 100 patients. Depression was reported in 23 patients of whom 19 had fatigue (P=0.015). 40 patients showed anxiety 33 of which had fatigue (P>0.001). 53 patients of whom reported to have pain (76 patients) showed fatigue (P=0.001). Insomnia was reported in 27 patients, where 21 of them had fatigue (P=0.036). Nocturia was reported in 10 patients, of whom 9 had fatigue (P=0.047). Spasticity was detected in 9 patients, all of whom had fatigue (P=0.012). Conclusion: There are several factors directly and indirectly associated with fatigue that are either fatigue-induced, caused by fatigue, or showing a two-way relationship with it. Understanding these links and attempting to reduce them will improve the quality of life for these patients