Introduction: In the last decades, cortisol has been extensively studied in association to early exposure to adversity as well as in the etiology of a number of physical and mental problems.While saliva and blood samples allow the measurement of acute changes in cortisol secretion, hair samples are thought to provide a valid retrospective measure of chronic cortisol secretion over an extended period of time. Nevertheless, the existing protocol for hair collection involves considerable financial and logistical challenges when performed in large epidemiological studies.Objective: This study aimed to validate an adapted collection protocol asking participants to sample their hair at home and to send it back to our laboratory by regular mail. Methods:Participants were 34 teenagers between 17 and 18 years of age. They participated in two hair collections: a) at home, with the help of someone they know, and b) in our laboratory, with a trained research assistant. Results: We noted a strong correlation between cortisol ascertained from hair collected at home and at the laboratory. No mean difference in cortisol levels could be detected between the two protocols. Moreover, we showed that a wide range of hair-related, sociodemographic, lifestyle factors that may be associated with hair cortisol levels did not affect the association between cortisol measures derived from each protocol. Conclusion: Our study provides initial support that reliable measures of chronic cortisol secretion could be obtained by asking adolescents to collect a sample of their hair at home and send them to the laboratory by regular mail. This adapted protocol has considerable financial and logistical advantages in large epidemiological studies.

There is a relative consensus about the detrimental impact of childhood maltreatment on later mental health problems and behavioral difficulties. Prior research suggests that neurophysiological stress mechanisms may partly mediate this association. However, inconsistent findings regarding hypothalamic-pituitary-adrenal axis and sympathetic responses to stress complicate this investigation. Furthermore, the concordance in these two stress systems is not well understood. We tested whether the severity of maltreatment affected the association between maltreatment and cortisol and heart rate (HR) stress responses and the symmetry of these responses. Participants were 155 males (56 maltreated and 99 controls) aged 18 to 35 years. Cortisol and HR were measured in response to the Trier Social Stress Test. Childhood maltreatment, sociodemographic factors, and health-related factors were measured using self-reported questionnaires. Maltreated participants had higher cortisol responses to stress in comparison to controls. However, a shift from moderate to lower to higher cortisol responses was noted as the severity of the experiences increased. Participants exposed to more experiences of maltreatment also showed a greater symmetry between cortisol and HR stress responses. Our findings provide further support for persistent dysregulation of the HPA axis following childhood maltreatment, of which the expression and symmetry with the sympathetic system may change according to the severity of experiences.

BackgroundSome evidence suggests that the prevalence of Borderline Personality Disorder (BPD) is elevated among male criminal offenders. It is not presently known whether offending, and violent offending, are limited to those presenting comorbid Antisocial Personality Disorder (ASPD) who have a childhood history of conduct problems and whether offending is linked to psychopathic traits.MethodsA community sample of 311 males followed from age 6 to 33 years, one third of whom had a criminal charge between ages 18 and 24, completed diagnostic interviews and the Psychopathy Checklist-Revised interview. Information on childhood included parent-reported family characteristics and teacher-rated of hurtful and uncaring behaviours, conduct problems, hyperactivity and inattention, and anxiety at age 6, 10, and 12 years. Health files were obtained as were records of criminal convictions from age 12 to 33.ResultsAt age 33, 4% of the men presented BPD and not ASPD, 16% ASPD and not BPD, 8% BPD + ASPD, and 72% neither disorder (ND). Comorbid disorders were common: BPD were distinguished by high levels of anxiety disorders, BPD and BPD + ASPD by depression disorders, and BPD, BPD + ASPD, and ASPD by substance dependence. Official files indicated use of health services by all participants. One-third of participants with BPD and BPD + ASPD acquired a diagnosis of a personality disorder. More than one-third of participants with BPD + ASPD obtained scores indicative of the syndrome of psychopathy. Convictions for violent crimes varied across groups: In adolescence, BPD none, BPD + ASPD 16%, ASPD 16%, and ND 3.6%; from age 18 to 33, BPD 18%, ASPD 19%, BPD + ASPD 52%, and ND 4.4%. Offenders with BPD + ASPD were convicted, on average, for four times more violent crimes than offenders with ASPD and seven times more than ND offenders. In childhood, men with BPD + ASPD and with ASPD had obtained similarly elevated ratings for disruptive behaviours as compared to ND.ConclusionBPD comorbid with ASPD was associated with violent criminal offending in adolescence and most strongly in adulthood, elevated levels of psychopathic traits, and childhood disruptive behaviour. BPD showed similar characteristics but to a much less degree.Electronic supplementary materialThe online version of this article (10.1186/s40479-017-0076-2) contains supplementary material, which is available to authorized users.