Role of interdependent self-construal in predicting acute salivary cortisol response, hair cortisol concentrations, and their associations.

Numerous studies have associated interdependent self-construal (InterSC) with heightened acute salivary cortisol stress responses in collectivist cultures. Hair cortisol concentration (HCC) is an important biomarker of chronic stress and is associated with acute salivary cortisol stress response. However, few studies have explored the association between InterSC and HCC. This study aimed to investigate the role of InterSC in the acute salivary cortisol stress response, HCC, and their associations. Seventy-seven healthy Chinese participants underwent assessments of InterSC, social anxiety, and HCC. The ScanSTRESS paradigm was used to induce an acute stress response and saliva samples were collected. These results replicated earlier findings showing that InterSC was associated with rapid salivary cortisol reactivity and recovery during acute stress. Additionally, InterSC was positively correlated with HCC, and social anxiety mediated this association. Importantly, InterSC moderated the HCC-acute salivary cortisol stress response association. Specifically, high HCC predicted a blunted acute salivary cortisol stress response in participants with low InterSC, including a slow salivary cortisol response during the acute stress reactivity phase and a small overall acute salivary cortisol response. However, this blunting effect was not observed with high InterSC participants, indicating that high InterSC buffered the blunting effect of HCC on the acute salivary cortisol stress response. In conclusion, this study provided new insights into how InterSC is associated with the hypothalamus-pituitary-adrenal axis stress system and revealed the dual-faceted role of InterSC for acute salivary cortisol stress and HCC.