Pain- and depression-related regional homogeneity changes in ankylosing spondylitis: a functional magnetic resonance...

Because of their ongoing pain, patients with ankylosing spondylitis (AS) are more likely to experience depression. Effective treatment remains a challenge. Additionally, the mechanisms of and relationships between AS-related pain and depression are inadequately understood. This study explored the regional homogeneity (ReHo) alterations linked to pain and depression in patients with AS.

In total, 43 patients with AS (40 men, 3 women) and 46 controls who were matched by age and sex were recruited. The patients were clinically assessed based on Bath Ankylosing Spondylitis Disease Activity Index, the Total Back Pain (TBP) and Hamilton Rating Scale for Depression (HAMD) scores, erythrocyte sedimentation rate, and high-sensitivity C-reactive protein level. The ReHo differences based on 3-T magnetic resonance imaging were compared between patients with and without AS. Associations between significant variables and pain and depression were further explored.

Patients with AS had decreased ReHo values within the left superior temporal gyrus and right paracentral lobule and increased values within the left precuneus and right middle frontal gyrus compared to healthy controls (p < 0.05, FDR correction). The left precuneus ReHo value negatively correlated with the TBP and HAMD scores. The right paracentral lobule ReHo value positively correlated with the AS duration and TBP score. The left precuneus had increased neural activity in patients with AS, which may lead to abnormal sensory responses, issues in emotion regulation, and deviations in information processing.

This work provides fresh understanding of the brain processes behind depression and pain associated with AS. Stratifying patients based on features with significant correlations with pain and depression could help identify those at risk and thus apply individualized treatment.