Acute Physical Stress Responses in Individuals with Chronic Psychological Stress: A Cold Pressor Test Study

Abstract

Chronic stress is a major public health concern associated with dysregulated physiological and psychological functioning. While responses to acute physical stressors have been studied in clinical populations such as chronic pain patients and individuals with major depression, limited attention has been paid to how non-clinical individuals experiencing chronic psychological stress respond to such challenges. This study examined whether individuals with chronic psychological stress differ from healthy controls in their behavioral, neuroendocrine, and subjective responses to an acute physical stressor.Forty non-clinical adults were stratified into a chronic stress group (n=20) and a healthy control group (n=20) based on the Quick Inventory of Depressive Symptomatology (QIDS; chronic stress: QIDS ≥ 6, healthy: QIDS ≤ 5). The experimental protocol consisted of a 5-minute initial rest period, followed by saliva sampling (S1), a Cold Pressor Test (CPT) phase in which participants immersed their hand in ice water for up to 180 seconds, a second saliva sampling (S2), a 10-minute guided breathing rest period, and a final saliva sampling (S3). Salivary cortisol concentrations were measured to assess HPA axis reactivity. Subjective ratings of relaxation, stress, and task difficulty were collected across four phases: initial rest, CPT, early recovery, and late recovery.The chronic stress group showed a significantly higher risk of withdrawing from the CPT than healthy controls (median: 59.4s vs. 180.0s; survival analysis, Cox HR=2.538, p=0.028). Salivary cortisol at baseline (S1) did not differ between groups (p=0.50). To account for individual differences in baseline cortisol, S2 and S3 values were normalized to S1 ((S-S1)/S1). The normalized cortisol change (S3-S2 normalized) was significantly correlated with CPT tolerance time in both groups (healthy: r=0.446, p=0.049; stress: r=0.604, p=0.006), with no significant difference between groups (Fisher z-test, all p>0.48). Subjective stress ratings during initial rest were significantly higher in the chronic stress group (p=0.017), whereas CPT ratings showed no group difference (both p>0.24). During late recovery, the chronic stress group showed trends toward lower relaxation (p=0.058) and higher stress (p=0.056).Despite prolonged exposure to psychological stress, the chronic stress group showed cortisol reactivity patterns comparable to healthy controls, suggesting that neuroendocrine responsiveness to acute physical stressors may remain relatively preserved in chronic stress populations. In contrast, although CPT tolerance was shorter in the chronic stress group, perceived stress and difficulty during the task did not differ between groups. Given that the chronic stress group reported higher baseline stress prior to CPT, entering the acute stressor in an already-stressed state may have reduced their capacity to sustain performance, rather than reflecting a more intense in-task experience. During late recovery, the chronic stress group showed trends toward lower relaxation and higher stress, consistent with their elevated baseline stress. This suggests that individuals with chronic stress may experience persistent stress and difficulty relaxing in quiet states, which may contribute to slower recovery following acute stress exposure. These findings reveal selective impairments in behavioral tolerance and psychological recovery, with no clear evidence of impaired neuroendocrine reactivity, advancing our understanding of how chronic psychological stress modulates acute stress responses.

Keywords: Chronic Stress, Cold Pressor Test, Acute Stress Response, Pain Tolerance, Cortisol Reactivity, Multimodal Assessment

DOI: 10.54941/ahfe1008201