Correlations between the Central Sensitization Inventory and measures of endogenous pain modulation in women with fibromyalgia.

BACKGROUND

The Central Sensitization Inventory (CSI) is a self-report measure to identify key symptoms of human assumed central sensitization (HACS). However, research examining how the CSI relates to experimental pain measures in a population with predominant HACS is scarce.

OBJECTIVES

This study examined correlations between the CSI and experimental pain measures in 54 women with fibromyalgia.

DESIGN

Cross-sectional study.

METHOD: The CSI was administered along with questionnaires of illness perception (i.e., IPQ), anxiety and depression (i.e., HADS), and health-related quality of life (i.e., RAND-36). Pressure pain thresholds (PPT), conditioned pain modulation (CPM), and exercise-induced hypoalgesia (EIH) were assessed. PPT were examined at (1) the center of the trapezius muscle, (2) the web space between the thumb and index finger, and (3) the proximal third of the calf muscle. For CPM, PPT were reassessed during and after immersion of the non-dominant hand in hot water. EIH was determined using the Aerobic Power Submaximal Exercise Test, after which PPT were reassessed. Absolute and percentage change scores in PPT during and after immersion (i.e., parallel and sequential CPM) and the submaximal exercise test (i.e., EIH) were calculated.

RESULTS

Only a negligible positive correlation between the CSI and parallel % CPM was found (r = 0.277, p = 0.046). Several weak-to-moderate correlations with the HADS, IPQ, and RAND-36 questionnaires suggest that the CSI is related to psychological constructs.

CONCLUSIONS

The results of the present study could not confirm associations between the CSI and experimental pain measures and suggest a closer relationship with psychological distress in patients with fibromyalgia.