Marianne Agergaard Vammen

A two-year follow-up study of salivary cortisol concentration and the risk of depression

Stress is a suspected cause of depression. High cortisol concentration, a biomarker of an activated stress response, has been found in depressed patients. The aim of this study was to determine if a high level of salivary cortisol is a risk factor of depression. In 2007, we enrolled 4467 public employees. Morning and evening salivary cortisol concentration were measured for each participant. Participants reporting high levels of depressive, burnout, or stress symptoms, assessed by questionnaires were assigned to a psychiatric interview. In this interview 98 participants were diagnosed with depression and subsequently excluded. Two years later in 2009, 2920 participants who had provided at least one valid saliva cortisol measurement at baseline participated at follow up. The psychiatric interviews were repeated and 62 cases of newly onset depression were diagnosed. Odds ratios of depression were estimated for every 1.0nmol/l increase in morning, evening, and daily mean cortisol concentration, as well as for the difference between morning and evening cortisol concentration. The risk of depression decreased by increasing daily mean cortisol concentration and by increasing difference between morning and evening concentrations, while morning and evening cortisol concentrations were not significantly associated with depression. The adjusted odds ratios for 1.0nmol/l increase in morning, evening, and daily mean cortisol concentration were 0.69 (95% CI: 0.45, 1.05), 0.87 (95% CI: 0.59, 1.28), and 0.53 (95% CI: 0.32, 0.90), respectively. The adjusted odds ratio for 1.0nmol/l increase in difference between morning and evening concentration were 0.64 (95% CI: 0.45, 0.90). This study did not support the hypothesis that high salivary cortisol concentration is a risk factor of depression, but indicate that low mean salivary cortisol concentration and a small difference between morning and evening cortisol concentration may be risk factors of depression.

Salivary cortisol and depression in public sector employees: cross-sectional and short term follow-up findings

INTRODUCTIONnIncreased cortisol levels have been suggested to play a role in the development of depression. An association has been shown in some studies but not consistently. The timing of an association is uncertain, and long-term follow-up studies may miss associations in narrower time windows. In the present study, we examined the association of several cortisol measures and depression in a repeated cross-sectional and short-term follow-up design. Depression was assessed by both self-reported symptoms of depression and clinical interviews.nnnMETHODnIn 2007, 10,036 public sector employees received a questionnaire along with salivary cortisol test tubes for home administration. Morning (30min after awakening) and evening (2000h) salivary samples were collected. Questionnaires and valid saliva samples were returned from 3536 employees. Approximately 3.6 months later a subsample of the participants collected three morning saliva samples (at awakening, 20min and 40min after awakening) plus an evening sample (2000h); participants with high baseline scores of self-reported depressive symptoms, burnout and perceived stress were invited to a standardized interview (SCAN) to detect clinical depression; and the symptom questionnaire was repeated for subsample participants. The study was repeated in 2009 with questionnaires and salivary test tubes (n=2408). In four cross-sectional and two short-term follow-up analyses odds ratios of depressive symptoms and of clinical depression were estimated by logistic regression for morning, evening, mean and the difference between morning and evening cortisol (slope). For the subsample, awakening response (CAR) and area under the curve (AUC) cortisol measures were calculated. We adjusted for sex, age, income, education, family history of depression, physical activity and alcohol consumption.nnnRESULTSnNone except one of the measures of salivary cortisol were associated with self-reported depressive symptoms or clinical depression, neither in the four cross-sectional analyses nor in the two short term follow-up analyses. E.g. in 2007, the adjusted odds ratios (OR) of depressive symptoms by a one unit increase in morning and evening cortisol (ln(nmol/litre saliva)) were 1.01 (95% CI: 0.88-1.17) and 1.05 (0.93-1.18), respectively. The one exception was significant at p=0.04 and was considered as due to chance.nnnCONCLUSIONnIn this large study, salivary cortisol was not associated with self-reported symptoms of depression or with clinical depression.

Does perceived stress mediate the association between workplace bullying and long-term sickness absence?

Objective: To examine if perceived stress mediated the association between workplace bullying and subsequent long-term sickness absence. Methods: The PRISME cohort was established in 2007 and re-examined in 2009. Questionnaire data about workplace bullying and perceived stress were obtained from 4114 individuals. Participants were followed in registers on long-term sickness absence (≥30 consecutive days of sickness absence). Results: Workplace bullying was associated with subsequent sickness absence (odds ratio [OR]u200a=u200a2.05; 95% confidence interval [CI]: 1.57 to 2.65) and concurrent high perceived stress levels (ORu200a=u200a2.34; 95% CI: 1.86 to 2.96). A high perceived stress level was also associated with subsequent sickness absence (ORu200a=u200a1.33; 95% CI: 1.13 to 1.56). Perceived stress explained 13% (95% CI: 6 to 23%) of the total association between bullying and sickness absence. Conclusions: The association between workplace bullying and subsequent long-term sickness absence may be partially mediated by perceived stress.

Emotional Demands at Work and the Risk of Clinical Depression: A Longitudinal Study in the Danish Public Sector

Objective: This study is a 2-year follow-up study of different dimensions of work-related emotional demands as a predictor for clinical depression. Methods: In a two-wave study, 3224 (72%) public employees from 474 work-units participated twice by filling in questionnaires. Sixty-two cases of clinical depression were diagnosed. Emotional demands were examined as perceived and content-related emotional demands, individually reported and work-unit based. Support, meaningful work, and enrichment were considered as potential effect modifiers. Results: Individually reported perceived emotional demands predicted depression (odds ratio: 1.40; 95% confidence intervals: 1.02 to 1.92). The work-unit based odds ratio was in the same direction, though not significant. Content-related emotional demands did not predict depression. Support, meaningful work, and enrichment did not modify the results. Conclusions: The personal perception of emotional demands was a risk factor for clinical depression but specific emotionally demanding work tasks were not.

Prolonged perceived stress and saliva cortisol in a large cohort of Danish public service employees: cross-sectional and longitudinal associations

PurposeIt is well known that acute stress can lead to a transient increase in cortisol secretion, but the effects of prolonged stress on cortisol secretion are uncertain. This study examines the cross-sectional and longitudinal associations between prolonged perceived stress and salivary cortisol.MethodsIn 2007, 4467 Danish public service employees participated in a study of stress and mental health, and 3217 participated in a follow-up in 2009. Perceived stress during the past 4xa0weeks was assessed by Cohen’s four item perceived stress scale. Participants were asked to collect saliva 30xa0min after awakening and at approximately 20:00 in the evening. The cortisol dependence on perceived stress was examined in regression analyses adjusted for effects of potential confounders. We adjusted for a large variation in saliva sampling times by modelling the time trajectory of cortisol concentrations in the morning and in the evening and examined if they were influenced by perceived stress.ResultsPerceived stress had no statistically significant effects on the level or time trajectory of morning or evening cortisol, neither cross-sectionally nor longitudinally. The 1xa0month prevalence of frequently perceived stress was low, approximately 2.5%.ConclusionOur results did not support the hypothesis that prolonged perceived stress is associated with the level or time trajectory of morning or evening salivary cortisol.

The associations between workplace bullying, salivary cortisol, and long-term sickness absence: A longitudinal study

BackgroundWorkplace stressors, such as bullying, are strongly related to subsequent long-term sickness absence, but little is known of the possible physiological mechanisms linking workplace stressors and sickness absence. The primary aim of this study was to investigate to what extent cortisol levels were associated with subsequent sickness absence and if cortisol mediated the association between workplace bullying and sickness absence. We additionally investigated possible bidirectional associations between bullying, cortisol, and long-term sickness absence.MethodsParticipants came from two Danish cohort studies, the “Psychosocial RIsk factors for Stress and MEntal disease” (PRISME) cohort and the “Workplace Bullying and Harassment” (WBH) cohort (nxa0=xa05418). Information about exposure to workplace bullying and morning and evening salivary cortisol was collected at three time points with approximately two years in between. After each data collection, all participants were followed for two years in registers, and cases with long-term sickness absence lasting 30 or more consecutive days were identified. The association between cortisol levels and subsequent sickness absence was assessed by logistic regression, while the extent to which the association between bullying and sickness absence was mediated by cortisol was quantified through natural direct and indirect effects.ResultsHigh evening cortisol was associated with a decreased risk of sickness absence (ORxa0=xa00.82, 95% CIxa0=xa00.68–0.99), but we did not find that high morning cortisol levels (ORxa0=xa00.98, 95% CIxa0=xa00.81–1.18) or high morning-to-evening slope (ORxa0=xa00.99, 95% CIxa0=xa00.82–1.18) were associated with subsequent sickness absence. We also tested for reverse causation and found that long-term sickness absence, but not salivary cortisol, was a strong risk factor for subsequent workplace bullying. There was no indication that cortisol mediated the association between workplace bullying and sickness absence.ConclusionWe found no straightforward and simple association between cortisol and long-term sickness absence. Furthermore, the association between workplace bullying and long-term sickness absence was not mediated by cortisol.

O20-6 Exhaustion and diurnal levels of saliva cortisol: cross-sectional and longitudinal associations in a large two-panel cohort study

Objectives To investigate cross-sectional and longitudinal associations between self-reported exhaustion and diurnal levels of saliva cortisol. Methods In a two wave cohort study of public service employees (baseline 2007, follow-up 2009), cortisol in saliva was measured in the morning and in the evening and exhaustion was measured by the scale of general burnout from the Copenhagen Burnout Inventory (six items on exhaustion, scored 1 to 5 (never, seldom, sometimes, often, always)). The material for cross-sectional analyses consisted of 3614/4000 and 2489/2813 persons with valid burnout and cortisol data morning/evening in 2007 and 2009, respectively. The corresponding material for longitudinal analyses included 2115/2588 persons. The natural log of cortisol was analysed as the dependent variable with exhaustion as the explaining variable in a model with mutually adjusted cross-sectional and longitudinal effects and adjustment for age, gender, saliva sampling times and awakening time. Results Cross-sectionally, high levels (often or always) of exhaustion was experienced by 8% of the study population, and the ratio of their morning cortisol level compared to those with the lowest levels of exhaustion was 0.90 (95% confidence interval 0.84–0.97, p = 0.008). The same tendency was found for evening cortisol, but this finding was not significant after adjustment. Exhaustion did not change the slopes of morning cortisol concentrations with saliva sampling time since awakening. There were no significant longitudinal effects. Conclusions High levels of exhaustion was associated with low morning cortisol levels in cross-sectional analyses but not in longitudinal analyses.

0268 Is perceived stress related to an increase in salivary cortisol

Objectives Perceived Stress is a suspected cause of many psychological and physical illnesses. However it remains to be discovered what physiological measures are involved. While it is widely known that acute stress leads to an increase in cortisol levels, the findings in prolonged stress research have not been consistent. This study explores the association between Perceived Stress and salivary cortisol levels using the largest population ever used in this field. Method 4467 public employees in the PRISME cohort in 2007. 3217 of those did a similar follow up study in 2009. A 4-item Danish version of the PSS-scale was used to measure perceived stress and operationalized as the average score. Salivary cortisol samples were taken at 30 min post awakening and at 8 pm. A mean value of cortisol was calculated. In our analysis we applied logarithmic transformation to the concentrations. Results Linear regression analysis done for the association between PSS-score and salivary cortisol levels showed no significant association between the two. For cortisol mean the regression resulted in β=-0.005(Cl: -0.036–0.026) in 2007 and -0.010(Cl: -0.047–0.028) in 2009. Cortisol morning analysis resulted in β= -0.013(Cl: -0.050–0.023) in 2007 and β= -0.003(Cl: -0.048–0.042) in 2009. Cortisol evening analysis resulted in in β= -0.000(Cl: -0.042–0.042) in 2007 and β= -0.007(Cl: -0.047–0.061) in 2009. Conclusions Overall this study does not provide any evidence that perceived stress is associated with salivary cortisol.

0173 Grouping strategies for exposure assessment of the psychosocial work environment

Objectives Individual response style, mood, expectations, and health status may affect reporting of the psychosocial work environment, and bias associations with outcomes. Reporting bias may be avoided by aggregating individual responses, ideally preserving exposure contrast. In this study, we examined the degree of exposure contrast yielded by different grouping strategies. Method In 2007, we enrolled 4489 public employees from Aarhus, Denmark in the PRISME-cohort, with follow-up in 2009. From pay-roll registers we grouped workers at 2 organisational levels: department (n = 22) and work unit (n = 751), and 3 occupational levels: sector (n = 7), profession (n = 46), and job title (n = 77). Exposures, calculated as means of items scored on 5-point Likert scales, included psychological demands, decision latitude, social support, effort, reward, and procedural and relational justice. To assess variance components, we fitted linear mixed effect models with exposures as dependent variables, and id and grouping variables as random effects. Results are reported as the contrast in mean exposure levels e.g. between-group variance/ (between-group variance +within-group variance). Results Within each hierarchy contrasts rose with increasing group-level detail. Grouping by either work unit (wu) or by job title (jt) contrasts were: psychological demands: 0.28(wu); 0.26(jt), decision latitude: 0.24(wu); 0.32(jt), social support: 0.24(wu); 0.06(jt), effort: 0.23(wu); 0.16(jt), reward: 0.19(wu); 0.12(jt), procedural justice: 0.24(wu); 0.14(jt), and relational justice: 0.29(wu); 0.04(jt). Conclusions Grouping by work unit gave the most consistent contrasts (0.19–0.29), while grouping by job title varied considerably (0.04–0.32). These preliminary findings suggest that grouping by work unit provided better exposure contrasts than grouping by job title for all exposures, but decision latitude.