Sex differences in cerebrospinal fluid proteomics of patients with restless legs syndrome

Study Objectives The pathobiology of restless legs syndrome (RLS) remains poorly understood, complicating effective treatment. This observational cross-sectional study aimed to identify a cerebrospinal fluid proteomic signature of RLS and to explore sex-specific differences in cerebrospinal fluid proteomics. Methods Cerebrospinal fluid samples were collected from 22 untreated RLS patients and 18 controls, matched for age, body mass index, and sex. Proteomic analysis was conducted using the SOMAscan platform, assessing over 7000 peptides. Results Eight proteins were differentially abundant between patients and controls, with CRP and JAML increased, and TAPBPL and IL1RL1 decreased. Pathway analysis highlighted significant involvement in immune response, coagulation, and cytoskeletal regulation. Analyses were then carried out using sex stratification, comparing men and women separately. Sex-specific analyses revealed more pronounced proteomic alterations in males (68 differentially abundant proteins vs. control males) than in females (17 proteins). Gene enrichment analysis revealed that men with RLS had more involvement in gene regulation and epigenetic factors than control males and women with restless legs syndrome had greater involvement in systemic inflammatory and vascular processes than control females. Conclusions This study identified a cerebrospinal fluid proteomic signature in RLS, implicating immune and inflammatory pathways in the disease's pathophysiology. Significant sex differences in protein level suggest potential sex-specific mechanisms in RLS, warranting further investigation. These findings contribute to the current understanding of RLS and could inform future therapeutic strategies.