Repeated measurement of salivary cortisol within and across days among shy young adults

Lower cortisol levels and attenuated cortisol reactivity to daily-life stressors in adults with 22q11.2 deletion syndrome

BACKGROUND

22q11.2 deletion syndrome (22q11DS) is a genetic disorder associated with neurodevelopmental, anxiety and mood disorders, as well as an increased risk for developing psychosis. Cortisol levels and stress reactivity reflect hypothalamic-pituitary-adrenal (HPA)-axis activity, and are believed to be altered in individuals that often experience daily-life stress, depression, and psychotic symptoms. However, it is unknown whether individuals with 22q11DS display an altered stress reactivity.

METHODS

We included 27 adults with 22q11DS (mean age: 34.1 years, 67% female) and 24 age and sex-matched healthy controls (HC; mean age: 39.9 years, 71% female) into an experience sampling study. Throughout 6 consecutive days, we measured participants' subjective stress related to current activity and at the same time collected salivary cortisol samples. Multilevel regression models were used to analyze cortisol reactivity to activity-related stress.

RESULTS

Diurnal cortisol levels were significantly lower in the 22q11DS group compared to HCs (B=-1.03, p < 0.001). 22q11DS adults displayed significantly attenuated cortisol reactivity to activity-related stress compared to HCs (B = -0.04, p = 0.026). Post-hoc exploratory analysis revealed that these results were independent from 22q11DS psychiatric diagnosis or medication use.

CONCLUSION

These results indicate that adults with 22q11DS have lower cortisol levels and attenuated cortisol response to daily stress, possibly resulting from an increased sensitization of the HPA-axis. This suggests that alterations in HPA-axis functioning, previously reported in several psychiatric disorders including post-traumatic stress disorder (PTSD), psychotic disorder, and mood disorder, also appear to be present in adults with 22q11DS.

Shyness, hormones, and quality of life among adults with schizophrenia

OBJECTIVE

Although individual differences in personality are known to influence quality of life in individuals with schizophrenia, relatively few studies have attempted to identify putative links underlying this relation.

METHODS

Here, we examined associations among temperamental shyness, hormones (ie baseline salivary cortisol and testosterone), and quality of life (QoL) measured in 42 stable outpatient adults with schizophrenia.

RESULTS

We found that baseline cortisol, but not testosterone, moderated the relation between shyness and QoL (ß = 1.09, p = 0.004). Among individuals with relatively low baseline cortisol, higher shyness was associated with lower Intrapsychic Foundations QoL. Individuals with relatively higher baseline cortisol reported similar QoL scores irrespective of level of shyness.

CONCLUSION

These preliminary results suggest that relatively lower baseline cortisol may be helpful to understanding the relation between temperament and Intrapsychic Foundations QoL in schizophrenia. The present findings are consistent with previous studies implicating relatively lower baseline cortisol levels in nonclinical samples of people who are shy and the negative downstream effects resulting from HPA axis dysregulation, and extends these prior findings to people with schizophrenia who are also shy.

Behavioral inhibition system and self-esteem as mediators between shyness and social anxiety

Shyness has been demonstrated to be an important factor associating with social anxiety. However, it is less clear on the mechanisms responsible for such association. The aim of the present study was to examine whether behavioral inhibition system (BIS) and self-esteem mediated the relationship between shyness and social anxiety. A sample of 521 healthy volunteers in the age range of 18-25 years completed self-report measures of BIS, self-esteem, shyness and social anxiety. Our correlational analyses showed that shyness was positively associated with social anxiety, supporting the overlapping and continuum hypotheses. Furthermore, BIS was positively correlated with shyness and social anxiety while self-esteem was negatively related to them, indicating that BIS and self-esteem were different in the relation between shyness and social anxiety. Importantly, results from structural equation modeling revealed that the relation between shyness and social anxiety was partially mediated by BIS and self-esteem, which suggested that they might play important roles in the relation between shyness and social anxiety.

Revisiting shyness and sociability: a preliminary investigation of hormone-brain-behavior relations

Shyness and sociability are two fundamental personality dimensions that are conceptually and empirically orthogonal and are conserved across cultures, development, and phylogeny. However, we know relatively little regarding how shyness and sociability are represented and maintained in the brain. Here we examined neural responses to the processing of different types of social threat using event-related fMRI, the salivary cortisol awakening response (CAR), and sociability in young adults selected for high and low shyness. Shy adults who exhibited a relatively higher CAR displayed neural activity in putative brain regions involved in emotional conflict and awareness, and were more sociable. In contrast, shy adults who displayed a relatively lower CAR exhibited neural activity in putative brain regions linked to fear and withdrawal, and were unsociable. Results revealed no systematic brain responses to social threat processing that correlated with the CAR in non-shy adults. These preliminary results suggest that individual differences in waking morning cortisol levels may influence neural processes that facilitate either social approach or withdrawal among people who are shy. Findings are discussed in relation to their theoretical and clinical implications for moving beyond longstanding descriptive to explanatory models of shyness and sociability and for understanding individual differences in social behavior in general.