Pain Phenotypes in Individuals With Multiple Sclerosis

This observational cross-sectional study aims to determine chronic pain phenotypes in individuals with multiple sclerosis (MS) and to investigate the clinical characteristics associated with different pain phenotypes. Participants with MS and chronic pain will undergo a comprehensive clinical assessment to identify nociceptive, neuropathic, nociplastic, and mixed pain phenotypes. The assessment will include clinical history, pain characteristics and distribution, quantitative sensory testing, pain intensity, disease severity, fatigue, health-related quality of life, and pain catastrophizing. The clinical characteristics of participants with different pain phenotypes will subsequently be compared.

Inclusion Criteria: * Age 18 years or older * Definite diagnosis of multiple sclerosis according to the McDonald criteria * No MS relapse or high-dose steroid treatment within the previous 3 months * Pain intensity ≥2 on the Numeric Rating Scale in at least one body region for at least 3 months * Ability to read, understand, and communicate in Turkish Exclusion Criteria: * Pregnancy * Severe psychiatric disorder and/or severe cognitive impairment confirmed by a neurologist or neuropsychiatrist * Presence of a serious pathology or disease that may compromise the assessment process or affect clinical decision-making, including metastasis, cancer, untreated or unhealed fractures, neurological disorders other than multiple sclerosis, or a history of diabetes