Patients with chronic pain have higher cross-network connectivity in the brain compared to healthy individuals, and men and women appear to have differences in the functional organization of the brain associated with chronic pain, according to a study published in Pain.
The study included data on functional magnetic resonance imaging at rest from a total of 220 participants, including 65 people with arthritis-associated chronic lower back pain and 155 healthy controls. Researchers used graph theory with modular analysis to compare the groups and determine if there were gender differences in how functional brain networks were organized.
There was a noticeable overlap in the graph partitions with the main intrinsic systems of the brain, such as the standard mode and the visual, central, and sensory motor modules. Compared to healthy controls, patients with chronic pain had higher network connectivity. Gender changes in the metric properties of the nodal graph were also found, and these changes were sometimes associated with chronic pain severity.
Women typically had higher functional segregation in both the middle and subgenual anterior cingulate cortex compared to men. In addition, women with the standard mode and the frontoparietal modules had less connectivity in the network. Men also showed connectivity with the sensorimotor module.
Classification models created by researchers based on nodal graph metrics could be used to classify a person’s gender and determine if they had chronic pain. The accuracy rates of these models ranged from 77% to 92% (P <0.001). Models within the module provided the best predictive accuracy for the classification between men and women and chronic pain.
Limitations of this study included the small sample size and the inclusion of patients with a single chronic pain condition, which may affect the generalizability of these results.
Despite the study’s methodological limitations, the researchers suggest that their results provide a framework for understanding gender differences in the brain that may reflect chronic pain.
Fauchon C., Meunier D., Rogachov A. et al. Gender differences in the modular organization of the brain in chronic pain. Pain. 2021; 162 (4): 1188-1888. 1200. doi: 10.1097 / j.pain.0000000000002104
This article originally appeared on Clinical Pain Advisor