Frida Eek

Exhaustion measured by the SF-36 vitality scale is associated with a flattened diurnal cortisol profile

The possible association between stress-related exhaustion and reduced activity in the hypothalamo-pituitary-adrenal (HPA) axis is increasingly in focus. The aim of the present study was to examine whether exhaustion measured in a non-patient population is associated with alterations in diurnal cortisol profile. The study population included 78 working individuals. The study group was dichotomised into exhausted and non-exhausted groups by means of the SF-36 vitality scale. Salivary cortisol was measured at three times during 1 workday: at awakening, 30min after awakening, and in the evening. The results showed that diurnal cortisol variation was significantly reduced in exhausted individuals. The difference in cortisol variation was mainly due to lowered morning cortisol in the exhausted group. Differences in cortisol levels at each sampling time or in mean diurnal output of cortisol were not statistically significant. The results would support the notion that exhaustion is associated with HPA axis hypoactivity as assessed by salivary cortisol. Furthermore, the SF-36 vitality provides a measure of exhaustion that may be useful in epidemiological studies in order to explore long-term health effects of stress-related exhaustion.

The role of saliva cortisol measurement in health and disease

This book is based on the wish to use saliva cortisol measurement because of its many advantages but frustrations over opposing results in the literature. Several discussions at different meetings led to the development of a network of researchers from Sweden, funded by the Swedish National Research Council. This network was soon expanded to also include colleagues from Norway and Denmark. The main aim of the group was to try to understand the results from different studies on saliva cortisol measurement and thereby better understand how and when saliva cortisol assessment best could be made. A hypothesis was that, seemingly, divergent findings could be effects of differences in the theoretic assumptions made and methods used. This led over to a decision to perform a literature review focusing on if the many different ways of evaluating the levels and dynamics of salivary cortisol especially with regard to time points of assessment and analyses of data affect the interpretation of cortisol measurement in various contexts.The aim of this book was to evaluate the usefulness of salivary cortisol as a biomarker in various settings. Our hypothesis was that observed diversities in results can be a function of different k ...The aim of the present chapter was to analyze whether measures of cortisol in saliva were associated with measures of sleep and to explore if divergent results were related to underlying differences in theoretic assumptions and methods. Measures of sleep quality included sleep duration, overall sleep quality, difficulty falling asleep, disturbed sleep, and sleep deprivation. Twenty-three papers were found to fulfil the inclusion criteria. Cortisol measures were grouped into single time points at different times during the day, deviations at different time periods during the day, reactivity and recovery after a standardized laboratory test, area under the curve and response to dexamethasone test. A large proportion of the studies included showed nonsignificant findings, which, in several cases, may be a result of low power. The most consistent results were a positive association between sleep duration and single measures of salivary cortisol at awakening, which was observed in 3 studies. In these studies, sleep duration was also associated with low evening cortisol levels, steep diurnal deviation of cortisol and/or high area under the curve. Together these findings suggest that longer sleep duration is related to a more dynamic cortisol secretion. Two of the 6 studies on disturbed or restless sleep showed relations to flat diurnal deviation and low laboratory stress test reactivity. This to some extent corroborates the findings on sleep duration. However, the many nonsignificant findings as well as the theoretical and methodological differences (e.g., heterogeneity in measures) complicate comparisons. Conflicting results may be at least partially due to differences in methods and underlying assumptions.

Effects of lifestyle factors on concentrations of salivary cortisol in healthy individuals

Objective. Salivary cortisol is widely used in occupational health research. However, many ordinary daily activities can influence the concentrations of cortisol and the interpretation of field studies. The aim of the present study was to evaluate the effect of lifestyle factors on salivary cortisol in everyday settings. Material and methods. Healthy employees participated in one or more sub‐studies on the effect of eating a vegetable salad versus protein‐rich mid‐day meal (n = 40), drinking coffee and smoking (n = 12), drinking alcohol (n = 32), awakening at different times (n = 29) and exercising (n = 21). Cortisol in saliva was measured by radioimmunoassay (RIA). Results. When eating a mid‐day meal, salivary cortisol was increased by 10 % (CI −1 % to 24 %) 1 h after eating compared to before eating in the case of both types of meal. Salivary cortisol increased by 80 % (CI 9 % to 199 %) after exercising compared to before exercise. The relative awakening response was approximately 100 % when using an alarm clock on both work‐days and days off. However, the awakening response was 39 % (CI 10 % to 75 %) on a day off with spontaneous awakening. No effects of alcohol, coffee or smoking were observed. Discussion. In field studies, the biological variation in salivary cortisol may be reduced by restricting physical exercise and in collecting pre‐meal samples. However, the protein content of food and moderate consumption of alcohol had no effect on concentrations of cortisol. Differences in relative awakening responses on work‐days and days off are related to time and mode of awakening.

Cortisol, sleep, and recovery — Some gender differences but no straight associations

BACKGROUND Work related fatigue has been suggested as a link in the assumed sequence of events between repeated adverse work demands and the development of work related stress, which may be associated with changes in concentrations of cortisol, psychological overload and, in the long run, health problems. Insufficient sleep is a contributing factor to lack of recovery, but previous studies on associations between subjective aspects of sleep and recovery, and cortisol, have been inconclusive. The aim with the present study was to examine possible associations between cortisol measures and (I) self-rated recovery, (II) occupational fatigue and (III) subjective sleep quality the night preceding cortisol sampling. Further, possible gender differences were tested. METHODS Salivary cortisol was measured in 581 persons during a working day, at awakening, +30 min and in the evening. Various measures of subjective sleep and recovery were analyzed in relation to cortisol. RESULTS Few correlations between cortisol and any sleep- or recovery parameters were found. However, some significant associations were found between cortisol and a few measures of more chronic aspects of sleep and recovery. Gender stratified analyses showed somewhat differing associations among men and women. This indicates that possible associations and pathways between lack of recovery/sleepiness and cortisol, and in the long run, unhealth, may not be similar for men and women.

Socioeconomic differences in smoking trends among pregnant women at first antenatal visit in Sweden 1982-2001: increasing importance of educational level for the total burden of smoking.

Background: There was a decrease in smoking during early pregnancy in Swedish women between 1982 and 2001. We sought to determine whether there was a parallel decrease in socioeconomic inequality in smoking. Methods: Registry data indicating educational level and smoking status at first antenatal visit in all 2 022 469 pregnancies in Sweden 1982–2001 were analysed. Prevalence differences, odds ratios based on prevalences and total attributable fractions were compared for five-year intervals. Results: The prevalence differences of smoking showed a greater decrease at the lowest and middle educational level compared with the highest educational level (14.5%, 15.7% and 10.2%, respectively) indicating reduced inequality in absolute terms. However, odds ratios regarding low educational attainment versus high, increased from 5.6 to 14.2, signifying increased inequality in relative terms. Moreover, the total attributable fraction of low and intermediate educational level regarding smoking at first antenatal visit increased from 61% to 76% during the period studied. Conclusions: Smoking at first antenatal visit in Sweden between 1982 to 2001 decreased in a way that conclusions regarding trends in inequalities in smoking at first antenatal visit depend on the type of measure applied. However, using the measure of total attributable fraction, which takes into consideration the impact of the exposure on the individual as well as the effect of the varying size of the group of exposed, the growing importance of educational level for the behaviour in the population was demonstrated.

Factors associated with prospective development of environmental annoyance

OBJECTIVES Idiopathic environmental intolerance (IEI) has in cross-sectional studies been associated with emotional problems and psychiatric disorders. However, in the absence of prospective studies it has not been possible to determine whether emotional problems precede the onset of IEI, or are a consequence of IEI. The purpose of this study was to address this issue in a prospective panel study design. METHODS The study sample (n=10 275) responded to a postal survey that included five questions regarding annoyance from environmental factors, at baseline and at follow-up five years later. Associations between a number of self-rating scales of stress, subjective health, and working conditions at baseline on one hand, and development of environmental annoyance from baseline to follow-up on the other, were examined. RESULTS Participants having developed environmental annoyance between baseline and follow-up had at baseline reported more subjective health complaints, higher levels of stress, strain, and lack of recovery, more dissatisfaction with their work situation, and lower personal social support, compared to participants not developing environmental annoyance. CONCLUSION Elevated subjective health complaints, high stress in daily life and a strained work situation, all possible signs of sustained arousal, increase the risk of developing annoyance to environmental factors. The results fit the hypothesis that reduced subjective health, over the course of time, may be attributed to environmental factors.

Differences in socioeconomic and gender inequalities in tobacco smoking in Denmark and Sweden; a cross sectional comparison of the equity effect of different public health policies

BackgroundDenmark and Sweden are considered to be countries of rather similar socio-political type, but public health policies and smoking habits differ considerably between the two neighbours. A study comparing mechanisms behind socioeconomic inequalities in tobacco smoking, could yield information regarding the impact of health policy and -promotion in the two countries.MethodsCross-sectional comparisons of socioeconomic and gender differences in smoking behaviour among 6 995 Danish and 13 604 Swedish persons aged 18-80 years.ResultsThe prevalence of smoking was higher in Denmark compared to Sweden. The total attributable fraction (TAF) of low education regarding daily smoking was 36% for Danish men and 35% for Danish women, and 32% and 46%, respectively, for Swedish men and women. TAF of low education regarding continued smoking were 16.2% and 15.8% for Danish men and women, and 11.0% and 18.8% for Swedish men and women, respectivelyThe main finding of the study was that the socioeconomic patterning of smoking, based on level of education and expressed as the relative contribution to the total burden of smoking exposure, was rather different in Sweden and Denmark. Moreover, these differences were modified by gender and age. As a general pattern, socioeconomic differences in Sweden tended to contribute more to the total burden of this habit among women, especially in the younger age groups. In men, the patterns were much more similar between the two countries. Regarding continued smoking/unsuccessful quitting, the patterns were similar for women, but somewhat different for men. Here we found that socioeconomic differences contributed more to overall continued smoking in Danish men, especially in the middle-age and older age strata.ConclusionThe results imply that Swedish anti-smoking policy and/or implemented measures have been less effective in a health equity perspective among the younger generation of women, but more effective among men, compared to Danish policy implementation. The results also raises the more general issue regarding the possible need for a trade-off principle between overall population efficacy versus equity efficacy of anti-tobacco, as well as general public health policies and intervention strategies.

Factors associated with BMI change over five years in a Swedish adult population. Results from the Scania Public Health Cohort Study.

Objectives: On account of the increasing worldwide problems associated with overweight and obesity, the aim of the present study was to examine BMI change over 5 years in relation to different lifestyle-, demographic- and psychosocial work-related factors. Methods: A cohort of 9913 persons responded to an identical survey in 2000 and 2005. BMI change over the period was examined in relation to gender, age, educational level, physical activity, job strain, and baseline BMI. Results: Mean BMI as well as prevalence of overweight and obesity increased in the cohort; most among younger persons. In all groups but younger women, BMI increase was greatest in the lowest baseline BMI quartile. Low education was associated with increased BMI at baseline, but not with BMI change over time except among young women. Exercisers had lower BMI than non-exercising persons, and exercise pattern over time was also significantly associated with BMI change. The greatest BMI increase was found among exercise drop-outs, while those who had taken up exercise during the study period were the only group who did not show a significant BMI increase over the study period. Job strain showed inconsistent associations with BMI change. Conclusions: Although socioeconomic differences in BMI were observed, these inequalities did not appear to be increasing, except among young women. Persons with a low initial BMI increased more in weight than persons with a high initial BMI. Exercise behaviour appeared to be an important factor for maintaining, or avoiding heavy increase in, BMI.

Effects on sleep-related problems and self-reported health after a change of shift schedule.

This study prospectively examined the effects of a change of shift schedule from a fast forward-rotating schedule to a slowly backward-rotating one. The initial schedule had a forward rotation from mornings to afternoons to nights over 6 consecutive days, with 2 days on each shift followed by 4 days off before the next iteration of the cycle, whereas the new schedule had a slower backward rotation from mornings to nights to afternoons, with 3 days on a given shift followed by 3 days off before the next shift. Shift workers (n = 118) were compared with a reference group of daytime workers (n = 67) from the same manufacturing plant by means of questionnaires covering subjective health, sleep and fatigue, recovery ability, satisfaction with work hours, work-family interface, and job demands, control, and support. Data were collected 6 months before implementing the new schedule and at a follow-up 15 months later. As predicted, on most dimensions measured the shift workers displayed clear improvements from initially poorer scores than daytime workers, and the daytime workers displayed no improvements.

A two-week monitoring of self-reported arousal, worry and attribution among persons with annoyance attributed to electrical equipment and smells

Non-patients attributing annoyance to either smells (smell annoyed; SA, n= 29) or electrical equipment (electrically annoyed; EA, n= 17), or both (generally annoyed; GA, n= 38), were monitored for 2 weeks through daily self-ratings of arousal (stress), sleep disturbances, health complaints, worry about hypersensitivity reactions, avoidance behaviors, and attributions of health complaints to electrical equipment and smells. In parallel, a demographically matched reference group was followed (n= 56). GA persons reported higher arousal (stress), more subjective health complaints, and more sleep disturbances than the other groups. About 60% in the GA and EA groups reported intentional avoidance behavior, compared to 31% in the SA group and 2% of the referents. Worry and attribution to environmental factors was also more frequent among GA persons than in the other groups. Thus, even at sub-clinical levels, environmental annoyance generalized to several triggers seems to be associated with behaviors commonly observed among patients with idiopathic environmental intolerance.