Neuropathic pain versus restless legs syndrome: distinct and combined effects on balance and walking performance in multiple sclerosis.

BACKGROUND: Restless legs syndrome (RLS) and neuropathic pain (NP) are commonly reported by persons with multiple sclerosis (MS, pwMS). The aim was to explore the effects of RLS and NP on walking and balance in pwMS, while also conducting a comparative analysis of MRI results. METHODS: A cohort of 1143 participants were divided into four groups: NP (n = 115), RLS (n = 166), both NP and RLS (n = 75), and controls (neither NP nor RLS) (n = 787). The Timed 25 Foot Walk Test (T25FW), Multiple Sclerosis Walking Scale-12 (MSWS-12), Timed Up and Go (TUG), Activities-Specific Balance Confidence (ABC) scale, Single-Leg Stand Test (SLST) were used to assess walking and balance. RESULTS: There were no significant differences between groups in T25FW and TUG performance. However, significant differences were found between groups regarding MSWS-12, ABC scale and SLST (p < 0.05). SLST was significantly lower in the NP + RLS group. MSWS-12 scores were significantly higher in both the NP-only and NP + RLS groups. ABC scores were significantly lower in all symptomatic groups. There were no significant differences between groups regarding MRI results. RLS severity showed small-to-moderate correlations with gait and balance outcomes. CONCLUSIONS: NP-only and the co-occurrence of RLS and NP were associated with lower perceived walking performance in pwMS.