A validation study on fingernail cortisol: correlations with one-month cortisol levels estimated by hair and saliva samples.

Several studies have focused on the cortisol levels in fingernail samples as a possible index of cumulative hormone production; however, the biological validity of fingernail cortisol has not been fully established. We investigated the association between cortisol levels in fingernail samples and other biological specimens, including hair and saliva samples, in healthy young adults to determine whether fingernail cortisol was associated with past cumulative hormone production. Participants were 23 adults (14 men and 9 women; mean age = 22.7 ± 2.8 years). Saliva samples were collected three times per day for 30 days, and hair samples (1 cm) from participants' scalps were obtained. Fingernail samples were repeatedly collected for 8 months, considering growth rate of fingernail and time lag for fingernails to fully extend from the nail matrix. Cortisol levels in hair samples were significantly associated with the levels in fingernail samples that were obtained 3 months after hair collection (r = .48, p < .05). The 30-day integrated area under the curve, based on salivary cortisol levels at awakening and bedtime, were significantly associated with cortisol levels in fingernail samples that were collected 2-5 months after saliva collection. This finding was especially significant after adjusting for the awakening time when the saliva was collected. This study provided evidence that fingernail cortisol was associated with cumulative hormone levels measured several months before but not those in the present. The samples may be useful for endocrinological evaluation in the investigation of chronic stress, cortisol levels, and health; moreover, the use of fingernail samples would permit larger-scale studies.

Imbalance Between Salivary Cortisol and DHEA Responses Is Associated with Social Cost and Self-perception to Social Evaluative Threat in Japanese Healthy Young Adults.

BACKGROUND: Social evaluative threat activates the HPA-axis system, namely cortisol and dehydroepiandrosterone (DHEA) responses. Additionally, cognitive and behavioral models in social anxiety, which is aroused anxiety symptoms in social situations, indicate that negative cognitions have a role in the maintenance of symptoms. Thus, the present study examined the relationship between HPA-axis activity and cognitive features in social situations. METHOD: We conducted the Trier Social Stress Test (TSST) with 44 male participants and assessed HPA-axis responses, fear of negative evaluation, the estimated social cost, and self-perceptions of their speech performance, which are core negative cognitions in social situations. RESULTS: Results revealed that the cortisol-DHEA ratio significantly correlated with self-perceptions of participants' speech performance (r = .30, p = .044) and the discrepancy between self-ratings and others' ratings of the speech (r = .44, p = .003). After controlling for depressive symptoms, significant correlations remained (r = .39, p = .01 and r = .50, p = .001, respectively). In addition, the estimated social cost, assessed before the speech task, significantly correlated with both the AUCg cortisol (r = .38, p = .011) and cortisol-DHEA ratios (r = .40, p = .007). CONCLUSION: These results suggest that estimating social costs in social situations, as well as distorted self-perceptions of that stressor, is related to dysfunctional endocrine regulation.

Effort-reward imbalance, cortisol secretion, and inflammatory activity in police officers with 24-h work shifts.

PURPOSE: Accumulating evidence shows that effort-reward imbalance (ERI) at work can cause various health problems. However, few studies have investigated the biological pathways linking ERI and health outcomes, and their findings have been inconsistent. In this study, we investigated the associations between ERI, the hypothalamic-pituitary-adrenocortical axis, and inflammation in a sample of police officers. METHODS: One hundred forty-two male police officers that were engaged in a working system of 24-h shifts were followed up during the work shift as well as during the two subsequent work-free days. Throughout this period, the participants provided two saliva samples each day for the 3-day period, and we measured the concentrations of cortisol and C-reactive protein (CRP) in the saliva. The police officers also completed the Japanese short version of the Effort-Reward Imbalance Questionnaire. RESULTS: The results of linear mixed model analyses controlled for possible confounding variables indicated that higher effort scores (p = 0.031) as well as effort-reward ratio (p = 0.080) were associated with lower cortisol levels, and the effect of effort was strengthened in the younger police officers (p = 0.017). Furthermore, higher effort scores were associated with higher CRP levels in younger police officers (p = 0.037). CONCLUSIONS: Our results indicate that effort, a component of ERI, has physiological effects in younger police officers, which possibly contribute to the development of stress-related diseases.

The diurnal patterns of salivary interleukin-6 and C-reactive protein in healthy young adults.

In recent years, salivary inflammatory markers, such as interleukin-6 (IL-6) and C-reactive protein (CRP), have been investigated regarding their relationships with psychosocial stress and stress-related diseases. This study investigated the diurnal patterns of salivary IL-6 and CRP in healthy young adults. Twenty-seven students (11 males and 16 females) participated in this study. The participants were instructed to provide saliva samples 8 times a day (at 0700, 0730, 1000, 1300, 1600, 1900, 2200, and 0100 h). For the duration of study, they were asked to wake up at 0700 h and go to bed after 0100 h. Twelve of the participants were asked to repeat this sampling procedure on two consecutive days to test the stability of the diurnal patterns. The salivary IL-6 levels peaked at awakening, gradually declined from morning to noon, and peaked again at midnight, before the participants went to sleep. The salivary CRP levels peaked at awakening, and they were lower during the daytime. The salivary IL-6 and CRP levels exhibited moderate to high stability over 2 days of sample collection. This study revealed that the salivary inflammatory markers had distinctive diurnal patterns.

[Effect of lifestyle and health behavior on neutrophil function].

OBJECTIVE: In this study, we investigated the relationships of neutrophil functions with lifestyle factors (namely, subjective stress, exercise habits, smoking habits, alcohol-drinking habits, and self-perceived status health) and health behavior in the Chinese urban elderly. METHODS: We performed a health survey of the elderly aged 65 years or older living in Tianjin. The subjects were 42 males (69.1 ± 4.1 years old) and 41 females (69.1 ± 4.1 years old). Investigations of subjective stress, exercise habits, smoking habits, alcohol-drinking habits, and self-perceived health status were performed. The phagocytosis and superoxide productivity of neutrophils were measured by the nitroblue tetrazolium (NBT) reduction method. In addition, leukocyte count and serum total protein (TP) level were examined. RESULTS: The investigations revealed the associations of health behavior (p<0.05) and self-perceived health (p<0.10) with the balance between phagocytosis and subsequent superoxide production. CONCLUSIONS: The present study revealed that there were correlations of neutrophil functions with lifestyle factors (subjective stress, exercise habits, smoking habits, alcohol-drinking habits, and self-perceived status health) and health behavior in the Chinese urban elderly.

The cortisol awakening response and autonomic nervous system activity during nocturnal and early morning periods.

The current study focuses on autonomic nervous system activity during sleep as a physiological aspect of sleep quality, and investigated the associations between the cortisol awakening response (CAR) and autonomic activity during sleep and after awakening. Ambulatory electrocardiograms were obtained from 20 participants, who also provided saliva samples (at the time of awakening, and 30, 45, and 60 min after awakening) and rated the subjective quality of their sleep at home. Autonomic activity was assessed with the Lorenz plot indices, cardiac sympathetic index (CSI) and cardiac vagal index. Total salivary cortisol secretion after awakening was calculated as area under the curve with respect to ground (AUC(G)) and increase (AUC(I)). After controlling for confounding factors, including sleep duration and awakening time, cortisol AUC(G) and AUC(I) were both found to be negatively correlated with CSI during the 30 min before and after awakening: before (r = -0.526 and -0.601 respectively) and after (r = -0.540 and -0.493 respectively). Self-reported sleep quality was not associated with the CAR. These results suggest that the CAR is negatively affected by basal sympathetic activity immediately before and after awakening, but not affected by subjective sleep quality. Physiological arousals around the time of awakening might inhibit the CAR.

Association between hair cortisol and diurnal basal cortisol levels: A 30-day validation study.

This study aimed to validate the association between hair cortisol and 30-day integrated salivary cortisol levels. Additionally, the intra-individual stability of the hair cortisol and the association between hair cortisol and salivary cortisol in several time domains were systematically explored. Twenty-four adults (15 men and 9 women, mean age: 22.7 ± 2.8 years) were asked to collect three saliva samples per day for 30 days, immediately after awakening (time 1), 30 min after awakening (time 2), and at bedtime (time 3). The hair sample was taken from the posterior vertex as close as possible to the scalp at the end of the 30-day study period. The area under the curve based on times 1 and 3 showed that cortisol levels in the 1 cm hair segment closest to the scalp were moderately correlated with the 30-day salivary cortisol levels (r = 0.41, p = 0.047). However, this correlation was not observed for the cortisol awakening response, diurnal slope, or other metrics in different time domains. The mean salivary cortisol at time 3 was significantly correlated with hair cortisol (r = 0.42, p = 0.041). Intra-individual stability of the hair cortisol was maintained for at least 4 months. Hair cortisol may reflect basal cortisol levels more substantially over longer periods (longer than 1 month and for at least 4 month), thus reflecting longitudinal cortisol production, rather than the day-to-day temporal cortisol response. Salivary cortisol is an ideal metric for short-term or day-to-day stress response. Researchers should select suitable metrics, such as hair cortisol for basal level (or trait) or salivary cortisol for response (or state), depending on the study objective.

Episodic stress associated with writing a graduation thesis and free cortisol secretion after awakening.

Cortisol secretion after awakening, an index of hypothalamus-pituitary-adrenal axis activity, appears to be related to psychosocial stressors, or to symptoms caused by psychosocial stressors. The relationship between the quality, duration, and magnitude of psychosocial factors and cortisol secretion is however, unclear. Therefore, the effect of episodic stress associated with writing a graduation thesis on cortisol secretion after awakening was investigated. Saliva samples were collected from 10 undergraduate students at awakening, and 30, 45, and 60 min after awakening 1 month, 2 weeks, and a few days before the thesis submission and 1 week after the submission. They also completed the Short form of Profile of Moods Scale (POMS-S) on the night before each sampling. Results indicated that cortisol levels were higher a few days before the thesis submission compared to 1 month before submission. Scores of "Fatigue" and "Tension-Anxiety" in POMS-S were also higher a few days before submission. These results suggest that episodic stress associated with writing a graduation thesis caused an increase in cortisol levels after awakening.

[Relationship between lifestyle and oral health in Chinese elderly].

OBJECTIVE: Oral health is very important particularly for elderly to live happily. The purpose of this study is to clarify the relationship between lifestyle and oral health in Chinese elderly. METHODS: The subjects were 96 men (mean +/- SD: 70.1 +/- 4.9) and 92 women (70.7 +/- 5.4). Oral health status was evaluated according to the numbers of remaining, intact, treated, and untreated teeth and score in WHO's CPI code. By carrying out a questionnaire survey, we evaluated lifestyle factors, such as stress (SCL-S), smoking habits, drinking habit, sleeping hours, sports, snack habit, and tooth brushing habit. Logistic regression analysis was used in analyzing the data. RESULTS: By multi-logistic regression analysis, men who smoke were more likely to have a lower CPI score than those who do not {odds ratio (OR) = 4.69, 95% confidence interval (95% CI) = 0.79-27.89, p < .10}. Men who brush their teeth less than once a day are less likely to have a lower CPI score than those who brush their teeth more than twice a day (OR = 0.33, 95% CI = 0.09-1.22, p < .10). On the other hand, women who experience much stress are more likely to have a lower CPI score than women who experience little stress (OR = 5.59, 95% CI = 1.29-24.15, p < .05). CONCLUSIONS: The study indicated that smoking may affect oral health conditions in men, whereas stress may affect oral health conditions in women. The reduction in stress and abstinence from smoking are important in maintaining good oral health in Chinese elderly.

Salivary 3-methoxy-4-hydroxyphenylglycol increases after awakening in healthy young adults.

Levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) may reflect central noradrenergic activity. In this study, we investigated salivary MHPG changes after awakening, and explored their relationships with cortisol and peripheral autonomic activity. The participants were 25 college students. Saliva samples were collected on awakening and 30 min after awakening to determine MHPG and cortisol. Ambulatory electrocardiograms were obtained to assess heart rate, cardiac sympathetic index (CSI), and cardiac vagal index (CVI) before and after awakening. MHPG levels increased significantly during the first 30 min after awakening. Similarly, cortisol, heart rate, and CSI increased during the 30 min after awakening, but changes in MHPG did not correlate with changes in cortisol, heart rate, CSI, and CVI during that period. This study demonstrated that salivary MHPG levels increase after awakening, in common with cortisol, heart rate, and cardiac sympathetic activity.

[Psychophysiological effects of hand massage in geriatric facility residents].

OBJECTIVES: Geriatric facility residents experience easy decrease of their quality of life (QOL) compared with elderly people cared for in their own homes owing to environmental changes. Because complementary and alternative medicine is useful to improve QOL, a simple manual for hand massage for inexperienced volunteers was developed, and the physical and psychological effects of this method were examined. METHODS: Thirty-six female geriatric facility residents (mean age, 84.5 years) were chosen. They were divided into two groups: the control and hand-massaged groups. In the hand-massaged group, females received 15 min hand massage from volunteers in accordance with a simple manual. No hand massage was performed in the control group. Before and after the treatment, a survey using a questionnaire (7 items; e.g., tension, fatigue) and physiological measurements (e.g., blood pressure, hand skin temperature), and measurement of cortisol and chromogranin A levels in saliva samples using enzyme-linked immunosorbent assay kits were carried out. Data were analyzed by two-way analysis of variance (ANOVA) to determine the effects of group and time on the dependent variables. RESULTS: The hand-massaged group showed greater increases in skin temperature than the control group, as shown by ANOVA (p<.05). Results showed that improvements of the scores in the questionnaire (condition and feel-good items) were greater in the hand-massaged group than in the control group (p<.05). Cortisol level increased in the control group, but was not statistically significantly different from that in the hand-massaged group, as shown by ANOVA. Chromogranin A level was also not significantly different between the two groups. CONCLUSIONS: These results confirmed the benefits of complementary and alternative medicine including touching and massage found in previous studies. Hand massage prompted relaxation in geriatric facility residents in this experiment.

The biological effects of acute psychosocial stress on delay discounting.

Organisms prefer to receive rewards sooner rather than later because they excessively discount the subjective value of future rewards, a phenomenon called delay discounting. Recent studies have reported an association between cortisol-which is secreted by the hypothalamic-pituitary-adrenal (HPA) axis-and delay discounting. However, no study has examined whether acutely induced psychosocial stress modulates delay discounting. Thus, the present study examined the effect of acute psychosocial stress and its hormonal and inflammatory correlates on the rate of delay discounting. To accomplish this purpose, we assessed the participants' discounting rates using the questionnaire version with inter-temporal choice before and after an acute psychosocial stress task (the Trier Social Stress Test; TSST). The results demonstrated that TSST increased rates of delay discounting in only cortisol responders (not in non-responders), indicating the possible influence of the pathway from the HPA axis to the dopaminergic systems under acute stress. Furthermore, the findings of correlation analysis indicated a U-shaped relationship between baseline level of C-reactive protein and delay discounting rate, suggesting a complex relationship between inflammatory markers and delay discounting rate.

An increase in salivary interleukin-6 level following acute psychosocial stress and its biological correlates in healthy young adults.

Although interleukin-6 (IL-6) has been investigated frequently in stress research, knowledge regarding the biological processes of IL-6 in association with psychosocial stress remains incomplete. This study focused on salivary IL-6 and reports its temporal variation and biological correlates following acute psychosocial stress. Fifty healthy young adults (39 male and 11 female students) were subjected to the psychosocial stress test 'Trier Social Stress Test' (TSST), wherein the participants were asked to deliver a speech and perform a mental arithmetic task in front of 2 audiences. Collection of saliva samples, measurement of heart rate, and assessment of negative moods by visual analogue scales were conducted before, during, and after TSST. Salivary IL-6 levels increased by approximately 50% in response to the TSST and remained elevated for 20 min after the stress tasks were completed. Cluster analyses revealed that individuals with sustained elevation of IL-6 levels following the TSST exhibited a lower cortisol response compared to individuals with lower IL-6 levels. In the correlation analyses, a greater IL-6 response was associated with a higher heart rate during the mental arithmetic task (r=.351, p<.05) and with a lower cortisol response (r=-.302, p<.05). This study demonstrates that salivary IL-6 levels are elevated for a relatively long period following acute psychosocial stress, and suggests that sympathetic activity and cortisol secretion are involved in elevation of salivary IL-6 levels.

Adrenal hormone response and psychophysiological correlates under psychosocial stress in individuals with irritable bowel syndrome.

OBJECTIVE: In this study, we investigated levels and relative ratios of adrenal hormones (including cortisol, dehydroepiandrosterone [DHEA], and DHEA-sulfate [DHEA-S]) and their psychophysiological correlates under acute psychosocial stress in individuals with irritable bowel syndrome (IBS). METHODS: Fifty-three college students participated in the study (male: 42, female: 11; mean age: 22.64years), including 13 individuals with IBS (IBS group) and 40 individuals without IBS (control group). The participants were exposed to a standardized laboratory stressor, which included delivering a speech and performing a mental arithmetic task. We measured subjective stress levels and salivary cortisol, DHEA, and DHEA-S levels at relevant time points before, during, and after the tasks. RESULTS: DHEA-S level and the DHEA-S/DHEA ratio in the IBS group were significantly lower than those in the control group, and the cortisol/DHEA-S ratio in the IBS group was higher than that in the control group throughout the experiment. In the IBS group, the appraisal of a threat was positively correlated with cortisol levels (r=0.61), and the appraisal of controllability was negatively correlated with cortisol levels (r=-0.64) and with the cortisol/DHEA ratio (r=-0.71). The control group showed a significant positive correlation between the appraisal of threat and cortisol levels (r=0.32). CONCLUSION: The present study indicates that individuals with IBS had lower DHEA-S levels, and that their stressful cognitive appraisals under acute psychosocial stress caused the effects of cortisol to dominate. This adrenal hormone response may be involved in exacerbating abdominal symptoms in individuals with IBS.

Effect of day-to-day variations in adrenal cortex hormone levels on abdominal symptoms.

INTRODUCTION: The hypothalamic-pituitary-adrenal axis is known to be related to abdominal symptoms, and the relationship between abdominal pain and cortisol secretory patterns has been previously investigated using a cross-sectional approach. Here, we investigated the effect of day-to-day variations in salivary cortisol and dehydroepiandrosterone-sulfate levels on abdominal symptoms in healthy individuals. METHODS: Eleven college students (4 males and 7 females) participated in this study. The participants were asked to collect their saliva immediately after awakening and before bedtime for eight consecutive days. They also completed a questionnaire about abdominal symptoms before bedtime. The linear mixed model was applied to analyze the effects of the day-by-day variability or the 8-day average adrenal hormone level (at awakening, before bedtime, slope from awakening to bedtime) on abdominal symptoms. RESULTS: The day-to-day variability of cortisol levels before bedtime was negatively related with loose stool, while the day-to-day variability of the cortisol slope was positively correlated with loose stool. A low 8-day average dehydroepiandrosterone-sulfate level at awakening was positively related with frequent bowel movements, loose stool, and long bouts of severe abdominal pain. Likewise, a low 8-day average dehydroepiandrosterone-sulfate slope was positively related with long bouts of abdominal pain. CONCLUSIONS: Low cortisol levels before bedtime and a steeper diurnal cortisol slope during the day may be related to bouts of diarrhea during the day.

Salivary cortisol and DHEA reactivity to psychosocial stress in socially anxious males.

The purpose of the present study was to examine Hypothalamus-Pituitary-Adrenal (HPA) axis reactivity in social anxiety. The present study used a standardized psychosocial stress protocol (the Trier Social Stress Test; TSST; [Kirschbaum, C., Pirke, K.M., Hellhammer, D.H., 1993. The 'Trier Social Stress Test'-a tool for investigating psychobiological stress responses in a laboratory setting. Neuropsychobiology 28, 76-81.]) with 11 higher-social-anxiety and 11 lower-social-anxiety male college students. Psychological responses and salivary cortisol and dehydroepiandrosterone (DHEA) reactivity and cortisol/DHEA ratio were assessed at seven different times. The results showed that there was a significantly lower cortisol responsiveness in the higher social anxiety group but there was no significant difference of DHEA responsiveness. Further analyses showed lower responses for the cortisol/DHEA ratio in the higher-social-anxiety group to the TSST. These results suggest that there may be reduced HPA axis reactivity to psychosocial stress in socially anxious people.

Salivary dehydroepiandrosterone secretion in response to acute psychosocial stress and its correlations with biological and psychological changes.

We investigated dehydroepiandrosterone (DHEA) secretion in response to acute psychosocial stress and the relations of DHEA secretion to cortisol secretion, cardiovascular activity, and negative mood changes. Thirty-three male students (mean age 22.6 years) were subjected to the psychosocial stress test "Trier Social Stress Test" (TSST), in which the participants were asked to deliver a speech and perform a mental arithmetic task in front of two audiences. Collections of saliva, measurements of blood pressure and heart rate, and assessments of negative mood by visual analog scales were conducted before, during, and after TSST. Acute psychosocial stress significantly increased salivary DHEA level by an average of 60% immediately after TSST. The peak of DHEA concentration preceded that of cortisol concentration by about 10 min. DHEA response was moderately correlated to cortisol response (r=.34, r(s)=.49) but not to cardiovascular response. Lower DHEA level and elevated cortisol/DHEA ratio during TSST were significantly and moderately correlated with increased negative mood during and after TSST. These results indicated that an acute increase in DHEA concentration under stressful situations might be partly mediated by the activity of hypothalamus-pituitary-adrenal axis and could have some significance in the improvement of negative mood.