OBJECTIVES: To test whether central sensitization was associated with greater fatigue, independently of musculoskeletal pain.
METHODS: 2477 prospective cohort study participants completed a baseline questionnaire comprising the Chalder Fatigue Scale (CFQ), pain, demographics, physical activity, anxiety, depression and medication use. In a clinical assessment of 290 (11.7%) participants, central sensitization was measured by the wind-up ratio test at the hand (WUR-H) and foot (WUR-F). Bioelectric impedance determined proportion body fat. All participants were followed up 12 months later, at which time they completed the CFQ. Linear regression, with inverse probability sampling weights, tested the relationship between WUR at baseline and CFQ at 12 months, adjusted for baseline CFQ, demographics, lifestyle factors, mental health and baseline pain.
RESULTS: At baseline, the median interquartile range WUR-H and WUR-F were similar (2.3 (1.5, 4.0) and 2.4 (1.6, 3.9) respectively) and did not differ by sex (difference WUR-H: -0.29, 95% confidence interval -1.28-0.71; WUR-F: -0.57 (-1.50-0.36) or age(WUR-H: -0.53, -1.49-0.43; WUR-F:-0.08, -0.98-0.82). WUR-H scores (β = 0.11, 95% confidence interval: 0.07-0.16) and WUR-F scores (0.13, 0.08-0.17) were positively associated with CFQ scores at follow-up, independently of baseline CFQ and other covariates. These associations were not explained by baseline pain.
CONCLUSION: Fatigue was predicted by central sensitization, independently of the presence of pain. For those seeking to treat fatigue, the benefit of interventions that reduce central sensitization should be investigated.
