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A recent study found that nearly 1 in 10 people with multisite pain in a representative sample of Japan’s population met criteria for central sensitization.

Nearly 1 in 10 individuals reporting multisite pain in a representative sample of the Japanese general population met criteria for central sensitization (CS), according to a study published online ahead of print in the Journal of Orthopaedic Science.

The study highlighted a critical link between widespread pain and underlying neuroplastic mechanisms that may influence the diagnosis and treatment of chronic pain disorders.

Prevalence & Predictors

“Central sensitization encompasses neuroplastic changes within the central nervous system, leading to increased responsiveness to noxious stimuli,” explained corresponding author Hiroshi Hashizume, MD, PhD, of Wakayama Medical University, and study coauthors. “This phenomenon contributes to the amplification and spread of pain sensations, manifesting as hyperalgesia and allodynia.”

Although CS has been linked with increased pain sensitivity in patients with chronic pain conditions, its relationship with pain distribution in the general population has been unclear.

“By controlling for potential confounders, such as age and sex, we sought to elucidate whether central sensitization independently predicts the presence of pain at multiple anatomical locations,” researchers wrote. “We could then identify preventive strategies and targeted interventions to reduce the burden of chronic pain.”

The researchers analyzed a subcohort of 739 adults (399 women and 340 men) from the large-scale, cross-sectional Wakayama Health Promotion Study who reported pain at 13 anatomical locations. The authors used the Japanese version of the Central Sensitization Inventory (CSI-J) to quantify symptoms, with a score of 30 or higher indicating CS.

CS Prevalence Significant, Pain Distribution Varies

According to the findings, the prevalence of CS was significant, affecting 9.5% of participants. CSI-J scores were higher among females than males.

The researchers found that pain distribution differed by sex. Among men, lower back pain (20.6%), shoulder pain (15.0%), and neck pain (10.6%) were the most prevalent conditions. For women, shoulder pain (20.6%), knee pain (20.1%), lower back pain (19.5%), and neck pain (16.3%) were the most prevalent.

Multivariate analysis revealed that higher CSI scores were independently associated with several pain locations, including headache, neck, shoulder, arm, lower back, hip, thigh, and knee pain. Notably, CS was 14.4 times more likely in individuals with three or more pain sites.

“Specific locations of pain, particularly those close to the trunk, are strongly associated with CS [central sensitization],” the authors wrote. “These findings underscore the importance of assessing CS in individuals with multisite pain for targeted management and treatment strategies.”