Gray Matter Density of the Dorsomedial Prefrontal Cortex Mediates the Relationship Between Catastrophizing and Anxiety in Somatic Symptom Disorder

Abstract

Objective Catastrophizing is commonly co-occurrence with anxiety in somatic symptom disorder (SSD). However, the quantitative relationship between catastrophizing and anxiety in SSD and its underlying neuropsychopathology remains unclear. Methods To address the issue, twenty-eight SSD patients and twenty-nine healthy controls (HCs) completed the Hamilton anxiety scale and the catastrophizing subscale of the cognitive emotion regulation questionnaire. Then they underwent structural magnetic resonance imaging and voxel-based morphometry analysis was performed to obtain gray matter density (GMD) of the dorsomedial prefrontal cortex (dmPFC). Results Independent samples t-tests showed no significance between SSD patients and HCs in the scores on the catastrophizing subscale and GMD of the dmPFC. However, correlation analysis found that catastrophizing was significantly positively associated with anxiety in SSD. Further, mediation analyses revealed that GMD of the dmPFC (bilateral medial Brodmann area 8) mediated the relationship between catastrophizing and anxiety in SSD. Conclusion These findings support Kirmayer’s disease model of SSD that catastrophic interpretations of somatic symptoms resulted in increased anxiety and demonstrate that the dmPFC may be a potential neural site linking catastrophizing and anxiety in SSD.

Scoping review update on somatic symptom disorder that includes additional Chinese data

“…23 24 A mediation analysis revealed that grey matter density of the bilateral medial Brodmann area 8 mediated the relationship between catastrophising and anxiety in SSD. 25 One study suggested that some brain-evoked components can partially affect or predict diseased cognition levels of patients with SSD, potentially providing significant guidance for predicting impaired cognition and carrying out targeted interventions earlier. 26…”

Individual Differences in Pain Catastrophizing and Regional Gray Matter Volume Among Community-dwelling Adults With Chronic Pain

“…For example, among women with chronic vulvar pain (N = 14), PC had significant positive correlations with left parahippocampal and left substantia nigra GMV 17. More recently, no significant associations were observed between PC and GMD within a somatic symptom disorder sample (N = 28) 18…”

“…11,17 Of greater concern, widely documented correlates of PC including pain severity [2][3][4] and depression 8 were neither assessed nor controlled in samples included in Galambos et al 10 review or recent extensions. 18 Hence, it is not clear whether identified GM correlates are unique to PC or a possible function of failing to control for established correlates of PC. In light of these limitations, methodological refinements including assessments within larger chronic pain samples and statistical control of key correlates including sex, age, pain severity, and depression would help to clarify the presence and nature of unique regional GMV correlates of PC within chronic pain samples.…”

“…Even though sample demographics can influence these relations, effects of sex, age, and pain duration have not been controlled consistently across GM studies of PC 11,17. Of greater concern, widely documented correlates of PC including pain severity2–4 and depression8 were neither assessed nor controlled in samples included in Galambos et al10 review or recent extensions 18. Hence, it is not clear whether identified GM correlates are unique to PC or a possible function of failing to control for established correlates of PC.…”

“…17 More recently, no significant associations were observed between PC and GMD within a somatic symptom disorder sample (N = 28). 18 Several methodological concerns with the existing literature may have contributed to inconsistent relations between PC and regional GM. First, variable relations between PC and GM indexes may be a partial function of particular syndromes under study or a degree of homogeneity versus heterogeneity in pain conditions that comprised samples.…”