An Exploratory Cross-Sectional Study of the Association Between Regular Cigarette Smoking and Level of Disability, Hand Dexterity, Cognitive Impairment, Fatigue, and Markers of Oxidative Stress in Male Patients With Relapsing-Remitting Multiple Sclerosis.

Cigarette smoking is a recognized risk factor for multiple sclerosis (MS) development and progression; however, the association between smoking and features of MS in male patients remains insufficiently explored. A cross-sectional exploratory study was conducted involving 31 male patients with approved relapsing-remitting MS (RRMS), divided into smokers (n = 9) and non-smokers (n = 22). The Symbol Digit Modalities Test (SDMT) and Paced Auditory Serial Addition Test (PASAT) were used to assess cognitive performance. Hand dexterity was evaluated using the 9-Hole Peg Test (9HPT). Depressive symptoms and disability were assessed via the Beck Depression Inventory (BDI) and the Expanded Disability Status Scale (EDSS), respectively. Fatigue and related factors were assessed using the Comprehensive Fatigue Assessment Battery for Multiple Sclerosis (CFAB-MS). Serum markers of oxidative stress and antioxidant status, including superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), total antioxidant capacity (TAC), malondialdehyde (MDA), and glutathione (GSH), were also measured. Smokers demonstrated significantly lower SDMT scores compared with non-smokers (36.86 ± 11.16 vs. 52.47 ± 18.54; p = .04), which was no longer significant after adjusting for EDSS and age. No significant differences were observed between groups in PASAT, 9HPT, EDSS, or BDI. Smokers reported higher anxiety and worry scores on the CFAB-MS (p < .05), while other fatigue-related domains were comparable between groups. Regarding the oxidative stress markers, a statistically significant difference was only detected in SOD activity. Regular cigarette smoking may be associated with decreased cognitive processing speed and increased anxiety in male patients with RRMS, which warrants further investigation.