Background: Depression is highly prevalent among individuals with chronic pain and strongly impacts pain intensity, psychological functioning, and health-related quality of life. Self-efficacy has emerged as a potentially modifiable resilience factor within this interplay, yet large-scale real-world evidence integrating self-efficacy into multidimensional pain–depression models remains limited. Methods: This cross-sectional registry-based analysis evaluated standardized patient-reported measures from chronic pain patients enrolled in the German Pain e-Registry. All variables were directionally harmonized and transformed into standardized deviation scores (hSDSs) relative to patients without depression. Group-level hSDS profiles for five DASS-21 depression severity strata (none, mild, moderate, severe, extreme) were compared across pain intensity, disability, psychological well-being, affective pain processing, quality of life, neuropathic pain features, and pain-related self-efficacy (PSEQ). Correlations and exploratory principal component analysis (PCA) were used to assess multivariate structure. PCA-informed path models were estimated to evaluate directional relationships between pain, function, depression, and self-efficacy. All directional and mediation models represent exploratory, theory-informed statistical frameworks and do not imply causal or mechanistic relationships. Results: Across all domains, hSDS values increased monotonically with depression severity, while self-efficacy showed the strongest inverse gradient. Exploratory PCA revealed a dominant severity component explaining most variance and a secondary affective–self-efficacy axis, supporting the conceptual separation between functional–physical and psychological–affective symptom clusters. In the bottom-up path model (pain → function → self-efficacy → depression), self-efficacy showed the largest indirect statistical contribution within the proposed path models, and the model explained 55% of depression variance (R2 = 0.55). In the top-down model (depression → affective pain → self-efficacy → pain), 45% of pain intensity variance was explained (R2 = 0.45), again with self-efficacy as a central mediating construct. Associations remained robust after adjustment for age, sex, and BMI, as well as during sensitivity analyses. Conclusions: This large real-world cohort demonstrates a highly coherent pattern of associations across biopsychosocial domains and highlights pain-related self-efficacy as a central statistical construct linking pain, functional impairment, and depressive symptom burden within the applied exploratory models. The findings suggest that self-efficacy occupies a key position in the interplay between pain and mood, and that pharmacological and non-pharmacological treatments traditionally used in chronic pain management may be associated with changes in this construct. Importantly, all directional and mediation analyses are exploratory and do not imply causal or mechanistic relationships. Therapeutic strategies aimed at enhancing self-efficacy may therefore represent promising targets for future research within multimodal pain management frameworks.
Überall et al. (Fri,) studied this question.