External Factors Modulating Pain and Pain-Related Functional Impairment in Cervical Dystonia

Little is known about factors modulating pain and pain-related functional impairment in isolated cervical dystonia (CD).

The aim was to assess the prevalence and interrelationship between pain-modulating factors and pain-related determinants of functional impairment and quality of life in CD.

We analyzed pain-aggravating and pain-relieving external factors, the degree of pain-related functional impact on routine activities, and the relationship between these and pain severity, using cross-sectional data collected using the Pain in Dystonia Scale (PIDS) from 85 participants with CD. Pairwise correlation analyses and age- and sex-adjusted linear regression models estimated the relationship between pain-modulating factors and pain severity, and the impact of pain severity, dystonia severity, and psychiatric symptoms on pain-related functional impairment and disease-specific quality of life (measured using the Craniocervical Dystonia Questionnaire-24).

Stress and prolonged fixed position were the most frequent and impacting pain triggers, with women reporting larger impact. The average impact of pain-relieving factors was lower than that of pain triggers. Physical exercise and social gatherings were the most impacted activities by pain in CD. The intensity of external modulating factors was a predictor of pain severity. Severity of pain, CD, and psychiatric symptoms independently predicted pain-related functional impairment, whereas quality of life was predicted by pain severity, pain-related functional impairment, and psychiatric symptom severity, but not dystonia severity.

The PIDS provides insight into external modulation and functional impact of pain in CD. The pattern of external modulation of pain in CD is in line with a multifactorial modulation and complex physiology.