Association between central sensitization and multisite pain in the general population: A cross-sectional analysis of The Wakayama Health Promotion Study.

Background: Central sensitization (CS), which is characterized by amplified nociceptive processing within the central nervous system, is a key mechanism underlying chronic pain disorders. Chronic pain is a significant global health issue; however, the relationship between CS and pain distribution in the general population remains unclear. This study aimed to investigate the association between CS and the number of locations of body pain in a representative sample of the general population.

Methods: This cross-sectional study included 739 participants (340 men, 399 women) from the Wakayama Health Promotion Study. CS was assessed using the Japanese version of the Central Sensitization Inventory (CSI-J), with scores of ≥30 indicating CS. Participants reported pain at 13 locations. Statistical analyses, including chi-square tests, Student's t-tests, and multiple regression analyses, were performed to determine the associations between Central Sensitization Inventory (CSI) scores and pain locations.

Results: Among the participants, 9.5 % were diagnosed with CS. Females had significantly higher CSI scores than males. Lower back pain (20.6 %) and shoulder pain (15.0 %) were most common in men, whereas shoulder pain (20.6 %), knee pain (20.1 %), and lower back pain (19.5 %) were most common in women. Multivariate analysis revealed that sex, headache, neck pain, shoulder pain, arm pain, lower back pain, hip pain, thigh pain, and knee pain were significantly associated with CSI scores. Participants with ≥3 locations were 14.4 times more likely to have CS.

Conclusions: This study highlights the significant prevalence of CS in the general population, with a higher prevalence in females. Specific locations of pain, particularly those close to the trunk, are strongly associated with CS. These findings underscore the importance of assessing CS in individuals with multisite pain for targeted management and treatment strategies.