The correlation between serum markers of oxidative stress and fatigue and related factors in minimally disabled patients with relapsing-remitting multiple sclerosis

Oxidative stress is recognized as a key pathological mechanism in multiple sclerosis (MS), and fatigue is one of the most prevalent and disabling symptoms. In this cross-sectional study, 85 patients diagnosed with relapsing-remitting MS (RRMS) and Expanded Disability Status Scale (EDSS) < 4.5 were recruited. Fatigue was evaluated by the Comprehensive Fatigue Assessment battery MS (CFAB-MS), which also assesses fatigue-related factors. Venous blood samples were collected to measure levels of glutathione peroxidase (GPX), catalase (CAT), malondialdehyde (MDA), reduced glutathione (GSH), total antioxidant capacity (TAC), and superoxide dismutase (SOD). Most correlations between oxidative stress markers and fatigue measures were not statistically significant. However, MDA levels showed significant positive correlations with Visual Analog Scale (VAS) scores for sleep problems (r:0.23, p-value:0.04); Walking problems VAS (r:0.31, p-value < 0.01); anxiety and worry (r:0.22, p-value < 0.05); and significant negative correlations with mood (r:-0.21, p-value < 0.05) and fatigue management (r:-0.22, p-value:0.04). Additionally, GSH levels were positively correlated with Fatigue VAS (r:0.24, p-value:0.02) and CAT was negatively correlated with stress VAS (r:-0.21, p-value:0.04). After applying the Benjamini-Hochberg correction, none of the correlations remained statistically significant. At an exploratory level, this study suggests that there is a minimal association between oxidative stress, fatigue and its related factors in minimally disabled RRMS patients.