Justify your disability! A simulated medical evaluation as a novel stress induction model in chronic pain

Maladaptive stress responses may exacerbate chronic widespread pain (CWP) and deserve further investigations. Yet, existing stress induction paradigms lack relevance for individuals with CWP. Patients often report intense stress in response to medical appointments due to the experience of stigma, distrust, and a lack of common understanding about their condition and level of disability. Hence, we developed the Social Benefits Stress Test (SBST), based on the Trier Social Stress Test, replacing the mock job interview, by a fake medical examination where the participant needed to justify their work incapacity. Forty women with CWP due to hypermobile Ehlers-Danlos syndrome or hypermobility spectrum disorders were included. They underwent a 30-min baseline, the SBST and a recovery period. The psychophysiological stress response was captured using self-reported stress ratings, continuous heart rate and electrodermal activity (EDA) monitoring, salivary cortisol and α-amylase levels. Compared to baseline, a significant increase in stress ratings was observed during the SBST, associated with a peak in salivary biomarkers. Heart rate variability analysis showed significant decreases in high frequency power (HF), increases in heart rate, low frequency power (LF) and in LF/HF ratio. EDA analysis revealed significant increases in skin conductance response (SCR). Subjective stress ratings correlated with physiological changes in α-amylase and LF/HF ratio. The SBST induced a reproducible stress response across subjective and physiological measures, validating this task as a relevant experimental model of social stress in chronic pain and a valuable tool for quantitative testing of clinically relevant stress responses in patients with persistent symptoms.