Fear of pain and cortisol reactivity predict the strength of stress-induced hypoalgesia.

BACKGROUND: Acute stress can have an effect on pain sensitivity, yet the direction of the effect - whether it is hypoalgesic or hyperalgesic - is mixed across studies. Moreover, which part of the stress response influences pain sensitivity is still unclear. In the current experimental study, we aim to examine the effect of acute stress on heat pain thresholds and pain tolerance levels in healthy participants, while taking into account individual differences in stress responses. METHODS: Forty-two healthy participants were randomly assigned to either a well-validated stress paradigm: the Maastricht Acute Stress Task (MAST; combining physical and psychological stressors) or to a nonstressful version of the task. Heat pain thresholds and tolerance levels were assessed at three times: prior to the MAST, immediately after the MAST during the presumed sympatho-adrenal medullary (SAM) response, and 15 min after MAST to cover the presumed hypothalamus-pituitary-adrenal (HPA) axis response. Stress responses were assessed both subjectively and physiologically. RESULTS: We observed that the acute stress induction led to increased heat pain thresholds, an effect that was present only in participants showing a cortisol response following stress induction and only in the presumed HPA axis time window. The strength of this hypoalgesic effect was further predicted by the change in cortisol and by fear of pain levels. CONCLUSIONS: Our findings indicate that the HPA axis - and not the autonomic - stress response specifically underlies this stress-induced hypoalgesic effect, having important implications for clinical states with HPA axis dysfunctions. SIGNIFICANCE: This experimental study shows that an acute stress induction - that combines physical and psychological stressors - increases heat pain thresholds, but not tolerance in healthy participants. Furthermore, the magnitude of this stress-induced hypoalgesic effect is predicted by cortisol reactivity and fear of pain, revealing specific involvement of the HPA axis stress system and interactions with pain-related psychosocial aspects.

Criminal behavior and emotional disorder: comparing youth served by the mental health and juvenile justice systems.

This study explored whether youth involved in joint service systems differed from single-agency users in terms of types of crimes committed and clinical functioning. Data from 4,924 youth involved in one county's public mental health and juvenile justice service systems were examined. Twenty percent of those youth receiving mental health services had recent arrest records, and 30% of youth arrested received mental health services. Of all youth arrested in the county, mental health service users had more arrests than non-mental health service users. A subsample of 94 mental health service users with arrests was matched on demographics with 94 mental health service users without arrests. Youth with arrests had a higher frequency of conduct disorder, higher Child Behavior Checklist Externalizing and Total Problem Scale scores, and more functional impairment on the Child and Adolescent Functional Assessment Scale as compared to youth without arrests. Implications for behavioral health service delivery were discussed.