Classification criteria for distinguishing cortisol responders from nonresponders to psychosocial stress: evaluation of salivary cortisol pulse detection in panel designs

OBJECTIVE

Hypothalamic-pituitary-adrenal axis reactivity to acute stimulation is frequently assessed by repeated sampling of salivary cortisol. Researchers often strive to distinguish between individuals who show (responders) and those do not show (nonresponders) cortisol responses. For this, fixed threshold classification criteria, such as a 2.5-nmol/l baseline-to-peak increase, are frequently used. However, the performance of such criteria has not been systematically evaluated.

METHODS

Repeated salivary cortisol data from 504 participants exposed to either the Trier Social Stress Test (TSST; n = 309) or a placebo protocol (n = 195) were used for analyses. To obtain appropriate classifications of cortisol responders versus nonresponders, a physiologically plausible, autoregressive latent trajectory (ALT) mixture model was fitted to these data. Response classifications according to the ALT model and information on the experimental protocol (TSST versus placebo TSST) were then used to evaluate the performance of different proposed classifier proxies by receiver operating characteristics.

RESULTS

Moment structure of cortisol time series was adequately accounted for by the proposed ALT model. The commonly used 2.5-nmol/l criterion was found to be overly conservative, resulting in a high rate of 16.5% false-negative classifications. Lowering this criterion to 1.5 nmol/l or using a percentage baseline-to-peak increase of 15.5% as a threshold yielded improved performance (39.3% and 26.7% less misclassifications, respectively).

CONCLUSIONS

Alternative classification proxies (1.5 nmol/l or 15.5% increase) are able to effectively distinguish between cortisol responders and nonresponders and should be used in future research, whenever statistical response class allocation is not feasible.

Examining the association between salivary cortisol levels and subclinical measures of atherosclerosis: the Multi-Ethnic Study of Atherosclerosis

OBJECTIVE

To investigate the association between salivary cortisol and two markers of subclinical cardiovascular disease (CVD), coronary calcification (CAC), and ankle-brachial index (ABI).

METHODS

Data from an ancillary study to the Multi-Ethnic Study of Atherosclerosis (MESA), the MESA Stress Study, were used to analyze associations of salivary cortisol data collected six times per day over three days with CAC and ABI. The authors used mixed models with repeat cortisol measures nested within persons to determine if specific features of the cortisol profile were associated with CAC and ABI.

RESULTS

A total of 464 participants were included in the CAC analysis and 610 in the ABI analysis. The mean age of participants was 65.6 years. A 1-unit increase in log coronary calcium was associated with a 1.77% flatter early decline in cortisol (95% CI: 0.23, 3.34) among men and women combined. Among women low ABI was associated with a steeper early decline (-13.95% CI: -25.58, -3.39) and a marginally statistically significant flatter late decline (1.39% CI: -0.009, 2.81). The cortisol area under the curve and wake to bedtime slope were not associated with subclinical CVD.

CONCLUSIONS

This study provides weak support for the link between cortisol and measures of subclinical atherosclerosis. We found an association between some features of the diurnal cortisol profile and coronary calcification and ABI but associations were not consistent across subclinical measures. There are methodological challenges in detecting associations of cortisol measures at a point in time with health outcomes that develop over a lifetime. Studies of short-term mechanisms linking stress to physiological processes related to the development of early atherosclerosis may be more informative.

The effect of stress on periodontitis: A clinicobiochemical study

BACKGROUND

Clinical and epidemiological data suggest that negative life experience events, like depression, may contribute to an increased susceptibility to periodontal disease.

AIM

To study the association between psychological stress and chronic periodontitis.

MATERIALS AND METHODS

One hundred and eleven dentate individuals, of age 40 years and above, were selected. The clinical examination included, the number of teeth present, plaque index, Probing Pocket Depth, and Clinical Attachment Level. Assessment of Psychological stress levels were done by a questionnaire and were correlated with salivary cortisol levels, which were estimated biochemically by using the Enzyme-Linked Immunosorbent Assay (ELISA) method.

RESULTS

Statistical analysis was done by using the student 't' test and Mann Whitney test. According to our observation, chronic periodontitis showed a significant correlation with hypercortisolemia (P<0.0001), work tension (P=0.04), economic problems (P<0.0001), clinical stress syndrome (P<0.0001), plaque index (P<0.0001), and unsecured job (P=0.003).

CONCLUSION

Stress may be considered as an important risk factor for periodontal disease. Routine salivary cortisol assessment may be an economical and useful diagnostic marker to rule out stress in periodontitis patients.

Effect of aromatherapy with orange essential oil on salivary cortisol and pulse rate in children during dental treatment: A randomized controlled clinical trial

Background:

Essential oils have been used as an alternative and complementary treatment in medicine. Citrus fragrance has been used by aromatherapists for the treatment of anxiety symptoms. Based on this claim, the aim of present study was to investigate the effect of aromatherapy with essential oil of orange on child anxiety during dental treatment.

Materials and Methods:

Thirty children (10 boys, 20 girls) aged 6-9 years participated in a crossover intervention study, according to the inclusion criteria, among patients who attended the pediatric department of Isfahan Dental School in 2011. Every child underwent two dental treatment appointments including dental prophylaxis and fissure-sealant therapy under orange aroma in one session (intervention) and without any aroma (control) in another one. Child anxiety level was measured using salivary cortisol and pulse rate before and after treatment in each visit. The data were analyzed using t-test by SPSS software version 18.

Results:

The mean ± SD and mean difference of salivary cortisol levels and pulse rate were calculated in each group before and completion of treatment in each visit. The difference in means of salivary cortisol and pulse rate between treatment under orange odor and treatment without aroma was 1.047 ± 2.198 nmol/l and 6.73 ± 12.3 (in minutes), which was statistically significant using paired t-test (P = 0.014, P = 0.005, respectively).

Conclusion:

It seems that the use of aromatherapy with natural essential oil of orange could reduce salivary cortisol and pulse rate due to child anxiety state.

Evaluation of cortisol levels in gingival crevicular fluid and saliva in anxious and non-anxious patients with chronic periodontitis

BACKGROUND

To evaluate gingival crevicular fluid (GCF) and salivary cortisol levels in anxious and non-anxious patients with chronic periodontitis.

MATERIALS AND METHODS

A total of 45 patients with a mean age 43.4 ± 6.12 years were assigned to three groups: Healthy control group (Group 1), group with chronic periodontitis but no anxiety (Group 2) and group with chronic periodontitis and with anxiety (Group 3). State - Trait anxiety inventory and Hamilton Anxiety rating scale were used to assess the anxiety levels of all the subjects. Clinical measures such as plaque index (PI), gingival index (GI), probing pocket depth (PPD) and clinical attachment level (CAL) were recorded. GCF and unstimulated whole saliva samples were collected, and cortisol levels were determined using ELISA kit.

RESULTS

PI, GI, PPD, and CAL were higher in Group 3. Hormone level was significantly higher in Group 3. A positive correlation was found among salivary and GCF cortisol and CAL in Group 3.

CONCLUSION

Based on the obtained results individuals with high-levels of anxiety seem to be more prone to have periodontal disease. Salivary and GCF cortisol levels can be used as biomarker for evaluating part of the etiopathogenesis of chronic periodontitis.

Diurnal salivary cortisol is associated with body mass index and waist circumference: the Multiethnic Study of Atherosclerosis

OBJECTIVE

Neuroendocrine abnormalities, such as activation of the hypothalamic-pituitary-adrenal (HPA) axis, are associated with obesity; however, few large-scale population-based studies have examined HPA axis and markers of obesity. We examined the cross-sectional association of the cortisol awakening response (CAR) and diurnal salivary cortisol curve with obesity.

DESIGN AND METHODS

The Multiethnic Study of Atherosclerosis Stress Study includes 1,002 White, Hispanic, and Black men and women (mean age 65 ± 9.8 years) who collected up to 18 salivary cortisol samples over 3 days. Cortisol profiles were modeled using regression spline models that incorporated random parameters for subject-specific effects. Cortisol curve measures included awakening cortisol, CAR (awakening to 30-min postawakening), early decline (30 min to 2-h postawakening), late decline (2-h postawakening to bedtime), and the corresponding areas under the curve (AUC). Body mass index (BMI) and waist circumference (WC) were used to estimate adiposity.

RESULTS

For the entire cohort, both BMI and WC were negatively correlated with awakening cortisol (P < 0.05), AUC during awakening rise, and early decline and positively correlated to the early decline slope (P < 0.05) after adjustments for age, race/ethnicity, gender, diabetes status, socioeconomic status, β-blockers, steroids, hormone replacement therapy, and smoking status. No heterogeneities of effects were observed by gender, age, and race/ethnicity.

CONCLUSIONS

Higher BMI and WC are associated with neuroendocrine dysregulation, which is present in a large population sample, and only partially explained by other covariates.

[A critical analysis of cortisol measurements: an update]

Serum cortisol measurement is a very useful tool in the biochemical evaluation of adrenocortical function. Since this hormone circulates in blood mainly linked to binding globulins but is also partially free, it can be measured not only in the blood but also in urine, saliva and other biological fluids and tissues. Basal determinations as well as dynamic testing may be performed to evaluate the circadian variations, to estimate the diurnal cortisol secretion and to analyze its relations with other components of the hypothalamic-pituitary-adrenal axis. Measurements of cortisol in blood, saliva and urine may reflect the cortisol secretion at the time of sample collection or during a 24 h span. Recently, it has been proposed the determination of cortisol in tissues such as hair and nails like a means of evaluating the hormonal status during prolonged periods. The aim of this paper is to update the methodology for measuring cortisol and its usefulness for the clinical diagnosis of troubles of the hypothalamic-pituitary-adrenal axis.

The role of daily activities in youths' stress physiology

PURPOSE

This study examined links between diurnal patterns of the stress hormone cortisol and time spent by adolescents in nine common daily activities.

METHODS

During eight consecutive nightly telephone interviews, 28 youths (n = 12 girls), 10-18 years of age, reported their daily activities. On 4 days, four saliva samples were also collected and assayed for cortisol. Multilevel models assessed within- and between-person associations between time in each activity and cortisol area under the curve (AUC), cortisol awakening response (CAR), morning peak (30 minutes after wake up), and daily decline (morning peak to bedtime).

RESULTS

Links with AUC were found for most activities; significant associations with cortisol rhythms suggested that most effects were due to anticipation of the day's activities. Specifically, on days when youths spent more time than usual on video games and television, they had lower AUCs, with lower morning peaks. Youths who spent more time reading (within-person) and in computer-related activities (between-person) had higher AUCs, with stronger CARs (within-person). Youths who slept more had lower AUCs, with lower morning peaks on both the between- and within-person levels. Amounts of time spent in clubs, and for older adolescents in sports, were also linked to lower AUCs. Finally, youths who spent more time in school/schoolwork had lower average AUCs, but on days when youths spent more time than usual in school, they had higher AUCs, stronger CARs, and steeper daily declines.

CONCLUSION

Beyond their known implications for psychological adjustment, youths' everyday activities are linked to stress physiology.

Frontal EEG/ERP correlates of attentional processes, cortisol and motivational states in adolescents from lower and higher socioeconomic status

Event-related potentials (ERPs) and other electroencephalographic (EEG) evidence show that frontal brain areas of higher and lower socioeconomic status (SES) children are recruited differently during selective attention tasks. We assessed whether multiple variables related to self-regulation (perceived mental effort) emotional states (e.g., anxiety, stress, etc.) and motivational states (e.g., boredom, engagement, etc.) may co-occur or interact with frontal attentional processing probed in two matched-samples of fourteen lower-SES and higher-SES adolescents. ERP and EEG activation were measured during a task probing selective attention to sequences of tones. Pre- and post-task salivary cortisol and self-reported emotional states were also measured. At similar behavioural performance level, the higher-SES group showed a greater ERP differentiation between attended (relevant) and unattended (irrelevant) tones than the lower-SES group. EEG power analysis revealed a cross-over interaction, specifically, lower-SES adolescents showed significantly higher theta power when ignoring rather than attending to tones, whereas, higher-SES adolescents showed the opposite pattern. Significant theta asymmetry differences were also found at midfrontal electrodes indicating left hypo-activity in lower-SES adolescents. The attended vs. unattended difference in right midfrontal theta increased with individual SES rank, and (independently from SES) with lower cortisol task reactivity and higher boredom. Results suggest lower-SES children used additional compensatory resources to monitor/control response inhibition to distracters, perceiving also more mental effort, as compared to higher-SES counterparts. Nevertheless, stress, boredom and other task-related perceived states were unrelated to SES. Ruling out presumed confounds, this study confirms the midfrontal mechanisms responsible for the SES effects on selective attention reported previously and here reflect genuine cognitive differences.

Associations between salivary testosterone and cortisol levels and neonatal health and growth outcomes

OBJECTIVES

Male vulnerability in health and growth outcomes has often been reported in very low birth weight (VLBW) preterm neonates. On the basis of gender-difference theories, possible associations were explored between the levels of postnatal salivary testosterone/cortisol and the outcomes of neonatal health/growth.

METHODS

This study used an exploratory and comparative research design. One-hundred-one mother-VLBW preterm neonate pairs were recruited from the neonatal intensive care unit (NICU) of a tertiary medical center in the Southeastern, US. Demographic information, health and growth variables of neonates, and pregnancy and labor variables of mothers were obtained from the medical record reviews and interviews of mothers. Saliva samples from each pair were collected between 9 and 60 days of age. The levels of testosterone and cortisol were determined by using an enzyme immunoassay methodology.

RESULTS

Linear regression analysis showed that neonatal health problems were positively associated with the levels of postnatal salivary testosterone and cortisol, while growth delays were positively associated with the levels of postnatal salivary testosterone after adjusting for the characteristics of neonates and mothers and day of saliva sampling. The salivary levels of testosterone and cortisol were higher in neonates than in mothers. A positive correlation between the levels of testosterone and cortisol was found in neonates and in mothers.

CONCLUSIONS

The level of postnatal salivary testosterone is a more reliable marker in assessing neonatal health and growth outcomes compared to salivary cortisol. Further research on both testosterone and cortisol measurements at various stages during the neonatal period may elucidate further these associations.

The stressed eyewitness: the interaction of thematic arousal and post-event stress in memory for central and peripheral event information

Both arousal during the encoding of stimuli and subsequent stress can affect memory, often by increasing memory for important or central information. We explored whether event-based (thematic) arousal and post-event stress interact to selectively enhance eyewitnesses' memory for the central aspects of an observed incident. Specifically, we argue that memory for stimuli should be enhanced when (1) the stimuli are encoded under arousal (vs. non-arousal), and (2) stress is experienced soon after the encoding episode. We designed an experiment that extended previous research by manipulating arousal without changing the stimulus material, distinguishing between central and peripheral event information, and using a dynamic, life-like event instead of static pictures. After watching a video depicting a burglary under high or low thematic arousal, psychosocial stress was induced or not induced by the Trier Social Stress Test (TSST). Salivary cortisol was measured at standard intervals. Consistent with our prediction, we found a significant post-event stress × thematic arousal × centrality interaction, indicating that the recognition advantage for central event items over peripheral event items was most pronounced under both high thematic arousal and post-event stress. Because stress was induced after encoding this interaction cannot be explained by possible differences at encoding, such as narrowed attention. The centrality effect of post-event stress under high thematic arousal was statistically mediated by the cortisol increase, which suggests a key role of the stress hormone. We discuss implications of our findings for psychological and neuroscientific theories of emotional memory formation.

Diurnal salivary cortisol and urinary catecholamines are associated with diabetes mellitus: the Multi-Ethnic Study of Atherosclerosis

The objective was to examine the cross-sectional association of diurnal salivary cortisol curve components and urinary catecholamines with diabetes status. Up to 18 salivary cortisol samples over 3 days and overnight urinary catecholamines were collected from 1002 participants in the Multi-Ethnic Study of Atherosclerosis. Diabetes was defined as a fasting blood glucose of at least 126 mg/dL or medication use. Cortisol curve measures included awakening cortisol, cortisol awakening response, early decline, late decline, and cortisol area under the curve (AUC). Urinary catecholamines included epinephrine, norepinephrine, and dopamine. Participants with diabetes had significantly lower cortisol awakening response (β = -0.19; 95% confidence interval [CI], -0.34 to -0.04) than those without diabetes in multivariable models. Whereas men with diabetes had a nonsignificant trend toward lower total AUC (β = -1.56; 95% CI, -3.93 to 0.80), women with diabetes had significantly higher total AUC (β = 2.62; 95% CI, 0.72 to 4.51) (P = .02 for interaction) compared with those without diabetes. Men but not women with diabetes had significantly lower urinary catecholamines compared with those without diabetes (P < .05). Diabetes is associated with neuroendocrine dysregulation, which may differ by sex. Further studies are needed to determine the role of the neuroendocrine system in the pathophysiology of diabetes.

Cushing's syndrome: Stepwise approach to diagnosis

The projected prevalence of Cushing's syndrome (CS) inclusive of subclinical cases in the adult population ranges from 0.2-2% and it may no longer be considered as an orphan disease (2-3 cases/million/year). The recognition of CS by physicians is important for early diagnosis and treatment. Late-night salivary cortisol, dexamethasone suppressiontesti, or 24-h urine free cortisol are good screening tests. Positively screened cases need stepwise evaluation by an endocrinologist. This paper discusses the importance of screening for CS and suggests a stepwise diagnostic approach to a case of suspected hypercortisolism.

Genetics of cortisol secretion and depressive symptoms: a candidate gene and genome wide association approach

BACKGROUND

Depressive patients often have altered cortisol secretion, but few studies have investigated genetic variants in relation to both cortisol secretion and depression. To identify genes related to both these conditions, we: (1) tested the association of single nucleotide polymorphisms (SNPs) in hypothalamic-pituitary-adrenal-axis (HPA-axis) candidate genes with a summary measure of total cortisol secretion during the day (cortisol(AUC)), (2) performed a genome wide association study (GWAS) of cortisol(AUC), and (3) tested the association of identified cortisol-related SNPs with depressive symptoms.

METHODS

We analyzed data on candidate SNPs for the HPA-axis, genome-wide scans, cortisol secretion (n=1711) and depressive symptoms (the Centre for Epidemiology Studies Depression Scale, CES-D) (n=2928) in elderly persons of the Rotterdam Study. We used data from the Whitehall II study (n=2836) to replicate the GWAS findings.

RESULTS

Of the 1456 SNPs in 33 candidate genes, minor alleles of 4 SNPs (rs9470080, rs9394309, rs7748266 and rs1360780) in the FKBP5 gene were associated with a decreased cortisol(AUC) (p<1×10(-4) after correction for multiple testing using permutations). These SNPs were also associated with an increased risk of depressive symptoms (rs9470080: OR 1.19 (95%CI 1.0; 1.4)). The GWAS for cortisol yielded 2 SNPs with p-values of 1×10(-06) (rs8062512, rs2252459), but these associations could not be replicated.

CONCLUSIONS

These results suggest that variation in the FKBP5 gene is associated with both cortisol(AUC) and the likelihood of depressive symptoms.

High prevalence of normal tests assessing hypercortisolism in subjects with mild and episodic Cushing's syndrome suggests that the paradigm for diagnosis and exclusion of Cushing's syndrome requires multiple testing

Many Endocrinologists believe that a single determination of eucortisolism or a single demonstration of appropriate suppression to dexamethasone excluded Cushing's syndrome, except in what was previously thought to be the rare patient with episodic or periodic Cushing's syndrome. We hypothesize that episodic Cushing's syndrome is relatively common and a single test assessing hypercortisolism may not be sufficient to accurately rule out or diagnose Cushing's syndrome and retrospectively examined the number of normal and abnormal tests assessing hypercortisolism performed on multiple occasions in 66 patients found to have mild and/or episodic Cushing's syndrome compared to a similar group of 54 patients evaluated for, but determined not to have Cushing's syndrome. We found that 65 of the 66 patients with Cushing's syndrome had at least one normal test of cortisol status and most patients had several normal tests. The probability of having Cushing's syndrome when one test was negative was 92% for 23:00 h salivary cortisol, 88% for 24-h UFC, 86% for 24-h 17OHS, and 54% for nighttime plasma cortisol. These results demonstrated that episodic hypercortisolism is highly prevalent in subjects with mild Cushing's syndrome and no single test was effective in conclusively diagnosing or excluding the condition. Rather, the paradigm for the diagnosis should be a careful history and physical examination and in those patients in whom mild Cushing's syndrome/disease is strongly suspected, multiple tests assessing hypercortisolism should be performed on subsequent occasions, especially when the patient is experiencing signs and symptoms of short-term hypercortisolism.

Elevated salivary α-amylase and cortisol levels in unremitted and remitted depressed patients

Abstract Objective. Major depressive disorder (MDD) is often associated with dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis via chronic stress. Psychosocial stress-induced activation of salivary α-amylase (sAA) represents sympathoadrenal medullary system (SAM) activity, and sAA has become an emerging biomarker for sympathetic nervous system activity. In contrast to salivary cortisol, sAA has been less extensively studied in depressed patients. The present study sought to address this problem by measuring sAA and salivary cortisol levels in patients with major depressive disorder. Methods. The authors recorded Spielberger State-Trait Anxiety Inventory (STAI) scores along with, levels of sAA and salivary cortisol in 28 patients with unremitted major depressive disorder, 43 remitted patients and 103 healthy volunteers. Results. STAI (State or Trait) measurements in unremitted patients with MDD were significantly increased compared with healthy controls and remitted patients. SAA and cortisol levels in unremitted patients were also significantly elevated compared to controls and remitted patients. Finally, sAA levels were significantly correlated with HRSD in unremitted patients with MDD. Conclusion. These preliminary results suggest that sAA may be a state-dependent marker of major depressive disorder in addition to salivary cortisol.

Genetic and environmental influences on cortisol regulation across days and contexts in middle-aged men

Cortisol is an indicator of hypothalamic-pituitary-adrenal axis responsivity to stress, but few twin studies have examined the heritability of cortisol concentrations in adults across the diurnal cycle and in different contexts. Saliva samples were provided by 783 middle-aged male twins on one laboratory and two home days as part of the Vietnam Era Twin Study of Aging. Significant cortisol heritability estimates were found for laboratory measures only: awakening (.56); 30 min after awakening (.48); 1000 h (.42); mean output across the day (.43); and mean cortisol awakening response (.64). Twin correlations at home were low. In the laboratory, they were unchanged for fraternal twins, but increased for identical twins. Greater measurement error at home did not appear to account for home-laboratory differences. The results suggest that genetic factors influence cortisol responses to specific environmental stressors. Thus, cortisol levels are correlated in identical twins only when they undergo similar experiences.

Socioeconomic and race/ethnic differences in daily salivary cortisol profiles: the multi-ethnic study of atherosclerosis

It has often been hypothesized that stress and its biological consequences mediate the relationship between low socioeconomic status (SES) or minority status and poor cardiovascular disease outcomes. The objective of this study was to determine if daily cortisol patterns, a biomarker of the stress response, differ by race/ethnicity and socioeconomic status. Data were collected from 935 Black, White and Hispanic adults age 48-90 years old. Salivary cortisol samples were collected six times per day over 3 days: at awakening, 30min later, at 1000h, noon, 1800h and at bedtime. Blacks and Hispanics had lower levels of wake-up cortisol and less steep early declines, while Blacks had flatter and Hispanics steeper late day declines relative to Whites. Similarly the low socioeconomic status group also had lower levels of wake-up cortisol and less steep decline during the early part of the day. These patterns remained after adjustment for health behaviors and psychosocial factors. This study finds an association between salivary cortisol and race/ethnicity and SES in a multi-ethnic study population. Further work is needed to determine the health consequences of these differences.

Cortisol Response Following Exposure Treatment for PTSD in Rape Victims

This study examined changes in salivary cortisol levels pre-to-post-treatment in adult female rape victims diagnosed with post traumatic stress disorder (PTSD) randomly assigned to be treated with either Prolonged Exposure Therapy or Eye Movement Desensitization and Reprocessing. Salivary cortisol was collected at baseline, session 3, and session 9. A significant decrease in salivary cortisol levels was observed in individuals classified as treatment responders in both treatment conditions. Findings suggest that successful exposure-based treatments for PTSD which result in trauma-related and depressive symptom reduction may impact the action of the hypothalamic-pituitary-adrenal axis as measured by changes in level of salivary cortisol from pre-to-post-treatment.

Stressor paradigms in developmental studies: what does and does not work to produce mean increases in salivary cortisol

The stress response system is comprised of an intricate interconnected network that includes the hypothalamic-pituitary-adrenocortical (HPA) axis. The HPA axis maintains the organism's capacity to respond to acute and prolonged stressors and is a focus of research on the sequelae of stress. Human studies of the HPA system have been facilitated enormously by the development of salivary assays which measure cortisol, the steroid end-product of the HPA axis. The use of salivary cortisol is prevalent in child development stress research. However, in order to measure children's acute cortisol reactivity to circumscribed stressors, researchers must put children in stressful situations which produce elevated levels of cortisol. Unfortunately, many studies on the cortisol stress response in children use paradigms that fail to produce mean elevations in cortisol. This paper reviews stressor paradigms used with infants, children, and adolescents to guide researchers in selecting effective stressor tasks. A number of different types of stressor paradigms were examined, including: public speaking, negative emotion, relationship disruption/threatening, novelty, handling, and mild pain paradigms. With development, marked changes are evident in the effectiveness of the same stressor paradigm to provoke elevations in cortisol. Several factors appear to be critical in determining whether a stressor paradigm is successful, including the availability of coping resources and the extent to which, in older children, the task threatens the social self. A consideration of these issues is needed to promote the implementation of more effective stressor paradigms in human developmental psychoendocrine research.

Poverty-alleviation program participation and salivary cortisol in very low-income children

Correlational studies have shown associations between social class and salivary cortisol suggestive of a causal link between childhood poverty and activity of the stress-sensitive hypothalamic-pituitary-adrenocortical (HPA) system. Using a quasi-experimental design, we evaluated the associations between a family's participation in a large-scale, conditional cash transfer program in Mexico (Oportunidades, formerly Progresa) during the child's early years of life and children's salivary cortisol (baseline and responsivity). We also examined whether maternal depressive symptoms moderated the effect of program participation. Low-income households (income <20th percentile nationally) from rural Mexico were enrolled in a large-scale poverty-alleviation program between 1998 and 1999. A comparison group of households from demographically similar communities was recruited in 2003. Following 3.5 years of participation in the Oportunidades program, three saliva samples were obtained from children aged 2-6 years from intervention and comparison households (n=1197). Maternal depressive symptoms were obtained using the Center for Epidemiologic Studies-Depression Scale (CES-D). Results were that children who had been in the Oportunidades program had lower salivary cortisol levels when compared with those who had not participated in the program, while controlling for a wide range of individual-, household- and community-level variables. Reactivity patterns of salivary cortisol did not differ between intervention and comparison children. Maternal depression moderated the association between Oportunidades program participation and baseline salivary cortisol in children. Specifically, there was a large and significant Oportunidades program effect of lowering cortisol in children of mothers with high depressive symptoms but not in children of mothers with low depressive symptomatology. These findings provide the strongest evidence to date that the economic circumstances of a family can influence a child's developing stress system and provide a mechanism through which poverty early in life could alter life-course risk for physical and mental health disorders.

Psychophysiological responses in the pre-competition period in elite soccer players

This study investigated pre-competition physiological and psychological states of eighteen elite soccer players. Salivary cortisol was assessed during a non- training day and before three league games. Affective states (unpleasant and pleasant, somatic and transactional emotions) were evaluated using the Tension and Effort-Stress Inventory before the three league games. Participants formed 2 groups, 11 starters and 7 non-starters, depending on the starting list established by the coach. All players reported more intense pleasant transactional and somatic emotions than unpleasant ones prior to all games (p < 0.05), and relatively stable profiles of these psychological responses were observed across the three league games. However, salivary cortisol levels increased during pre-game for all players in comparison with the non- training day (p < 0.001). This anticipatory rise was only related to unpleasant somatic emotions (p < 0.001). This demonstrates that cortisol can be used as an index of emotional response to competition. Key pointsElite athletes perceive the participation to competition as a challenging situation as they experience more pleasant emotions than unpleasant ones in the pre-competition period. This profile is relatively stable across three league games, which is possibly due to the athletes' experience at this level.Participation to competition lead to anticipatory acute response of cortisol in the pre-competition period, which potentially prepares the athlete to perform.These responses are not related to status player (e.g., starter versus non-starter)Physiological stress (e.g. anticipatory rise in cortisol concentrations) is related to negative somatic emotions.Cortisol may constitute a measure of emotional response in pre-competition period.

Ecological salivary cortisol analysis-- part 2: relative impact of trauma history, posttraumatic stress, comorbidity, chronic stress, and known confounds on hormone levels

BACKGROUND

Although bio-psycho-social health research is an ideal, samples adequate for complex modeling require biomarker specimens from hundreds of participants. Ecological sampling departs from laboratory study norms, with implications for analysis.

OBJECTIVE

To inform ecological study designs, this article compares salivary cortisol levels and effect sizes of "focal" psychiatric factors, such as trauma history, posttraumatic stress diagnosis, comorbidity, and chronic stress, and "nuisance" factors, including endocrine disorders and medications and physiological factors such as gestational age and smoking.

STUDY DESIGN

This is a descriptive analysis of ecologically collected cortisol specimens, assayed in an ongoing perinatal psychobiological study, addressing methodological considerations.

RESULTS

Focal and nuisance factors are often interdependent with similar effect sizes. Careful specimen deletion decisions and model specification are needed to achieve the hoped-for external validity while maintaining internal validity.

CONCLUSIONS

Results of multivariate models lend support to the validity and usefulness of an ecological approach to incorporating biomarkers in health research. J Am Psychiatr Nurses Assoc, 2008; 14(4), 285-296. DOI: 10.1177/1078390308321939.

Ecological salivary cortisol specimen collection--part 1: methodological consideration of yield, error, and effects of sampling decisions in a perinatal mental health study

BACKGROUND

Current health research strives to integrate biological, psychological, and social factors consistent with ecological models. Home-based biomarker specimens are consistent with an ecological approach, but deviations from laboratory norms could affect validity of results.

OBJECTIVE

This article uses salivary cortisol specimens collected early in a perinatal mental health study to describe (a) return rate and returner characteristics, (b) adherence to procedures, (c) sources of laboratory error, (d) effects of deleting specimens with "nuisance" factors, and (e) effects that selection bias could have on cortisol concentration distribution.

STUDY DESIGN

This includes methodological analysis of collection, assay, and preanalysis decision components.

RESULTS

Rates of return do not differ by participants' sociodemographic, perinatal, or psychiatric characteristics. Excluding smokers affects representativeness. Selection bias in favor of more or less disadvantaged participants affects cortisol distribution.

CONCLUSIONS

The large yield of useable specimens permits multivariate modeling of cortisol level in association with health outcomes, potentially enhancing ecological validity. J Am Psychiatr Nurses Assoc, 2008; 14(4), 273-284. DOI: 10.1177/1078390308322944.

Evidence for T-helper 2 shift and association with illness parameters in chronic fatigue syndrome (CFS)

Few immunological markers have been consistently reported in CFS. However, a shift to a T-helper 2 (Th2) type immune response has been hypothesized for individuals with CFS. The current study investigated whether individuals with CFS who exhibited a stronger shift towards a Th2 type of immune response would also exhibit more severe symptoms, poorer neurocognitive functioning, and poorer physical and psychosocial functioning. The current investigation measured the percentage of Th1-like and Th2-like memory cells using cell surface flow cytometry in 114 individuals with CFS. The associations between the ratio of Th1 and Th2 memory cells and various illness parameters measures were then examined, including symptom severity, psychiatric functioning, neurocognitive functioning, salivary cortisol levels, and chronic pain status. Results indicated that individuals who exhibited a more extreme shift towards a Th2 immune response also exhibited poorer sleep and high levels of basal salivary cortisol. The implications of these findings are discussed.