Shift work disorder among oil rig workers in the North Sea.

STUDY OBJECTIVES: Shift work disorder (SWD) is a circadian rhythm sleep disorder caused by work hours during the usual sleep period. The main symptoms are excessive sleepiness and insomnia temporally associated with the working schedule. The aim of the present study was to examine SWD among shift workers in the North Sea. DESIGN AND PARTICIPANTS: A total of 103 shift workers (2 weeks on 7 nights/7days, 12-h shifts, 4 weeks off), mean age 39.8 years, working at an oil rig in the North Sea responded to a questionnaire about SWD. They also completed the Pittsburgh Sleep Quality Index, Bergen Insomnia Scale, Epworth Sleepiness Scale, Composite Morningness Questionnaire, Subjective Health Complaint Inventory, Demand/Control, and Instrumental Mastery Oriented Coping (based on the Utrecht Coping list). Most of these instruments were administered during the first day of the 2-week working period, thus reflecting symptoms and complaints during the 4-week non-work period. The shift workers were also compared to day workers at the oil rig. RESULTS: Twenty-four individuals were classified as suffering from SWD, yielding a prevalence for SWD of 23.3%. During the 4-week non-work period, individuals with SWD reported significantly poorer sleep quality, as measured by the Pittsburgh Sleep Quality Index, and more subjective health complaints than individuals not having SWD. There were no differences between the 2 groups in sleepiness, insomnia, circadian preference, psychological demands, or control. Individuals with SWD reported significantly lower scores on coping. The reports of shift workers without SWD were similar to those of day workers regarding sleep, sleepiness, subjective health complaints, and coping. CONCLUSIONS: The prevalence of SWD was relatively high among these shift workers. Individuals with SWD reported poorer sleep quality and more subjective health complaints in the non-work period than shift workers not having SWD.

Cognitive-behavioural therapy v. mirtazapine for chronic fatigue and neurasthenia: randomised placebo-controlled trial.

BACKGROUND: Single interventions in chronic fatigue syndrome have shown only limited effectiveness, with few studies of comprehensive treatment programmes. AIMS: To examine the effect of a comprehensive cognitive-behavioural treatment (CCBT) programme compared with placebo-controlled mirtazapine medication in patients with chronic fatigue, and to study the effect of combined medication and CCBT. METHOD: A three-armed randomised clinical trial of mirtazapine, placebo and a CCBT programme was conducted to investigate treatment effect in a patient group (n=72) with chronic fatigue referred to a specialist clinic. The CCBT programme was compared with mirtazapine or placebo therapy for 12 weeks, followed by 12 weeks treatment with a mixed crossover-combination design. Assessments were done at 12 weeks and 24 weeks. RESULTS: By 12 weeks the treatment effect was significantly better in the group initially receiving CCBT, as assessed with the Fatigue Scale (P=0.014) and the Clinical Global Impression Scale (P=0.001). By 24 weeks the treatment group initially receiving CCBT for 12 weeks followed by mirtazapine for 12 weeks showed significant improvement compared with the other treatment groups on the Fatigue Scale (P<0.001) and the Clinical Global Impression Scale (P=0.002). Secondary outcome measures showed overall improvement with no significant difference between treatment groups. CONCLUSIONS: Multimodal interventions may have positive treatment effects in chronic fatigue syndrome. Sequence of interventions seem to be of importance.

Coffee, stress and cortisol in nursing staff.

According to cognitive activation theory, long-lasting work demands without rest or lack of coping may lead to sustained activation and pathology. Cortisol is one of the most important stress hormones in humans and increased basal levels of cortisol are considered a valid marker for sustained activation. In order to investigate this association further, we investigate the relationships between salivary cortisol profiles, job stress, work load (effort/reward, demand/control) and health (subjective health complaints and health-related quality of life) in a population of health care workers. Forty-four women filled in a questionnaire and collected five saliva samples on two consecutive working days (1: wake-up time, 2: wake-up time+30 min, 3: wake-up time+45 min, 4: 1500 h and 5: 2200 h). There was no relationship between psychosocial factors at work and cortisol levels in the morning (cortisol level at wake-up time and awakening cortisol response (ACR)). Only the confounding variable tobacco reached a significant level in the hierarchical regressions analyses. Our significant findings are limited to the afternoon decline and the evening values. The decrease during the day relates to decision authority, physical functioning, general health, and vitality in the single, unadjusted regression analyses. The decrease also relates to coffee intake, which we included originally as a confounding variable. In the final hierarchical regression of the evening values, only decision authority and coffee were significantly related to cortisol levels in the evening.

Neurasthenia, subjective health complaints and sensitization.

Patients (n=997) visiting general practitioners in an area in Western Norway completed a battery of questionnaires related to subjective health complaints and fatigue. An additional 78 patients were referred directly to the hospital for neurasthenia. After screening the questionnaires and interviews with a selected sample, a total of 73 patients were finally accepted as 'neurasthenia' patients satisfying the ICD-10 diagnosis. These patients were compared with the remaining 1002 patients. Patients with neurasthenia had more prevalent and more severe subjective health complaints, particularly pseudoneurological and musculoskeletal complaints than the reference population of patients. They reported low levels of instrumental coping and poorer physical fitness, in spite of a comparable level of self reported physical activity and exercise. Women were over-represented in this group. This overall higher score on subjective complaints from all organ systems is in accordance with the hypothesis of an overall and general sensitization to the afferent inputs from their psychophysiological systems.

Mutilation anxiety differs among females with fibromyalgia and functional dyspepsia and population controls.

BACKGROUND: Studies using self-report rating scales suggest a considerable overlap regarding symptom complaints in patients with fibromyalgia (FM) and functional dyspepsia (FD), while clinical assessments point to important psychological differences. PURPOSE: To test the hypothesis that measurement of psychological state by means of content analysis of speech will demonstrate differentiation between the two patient groups and between patients with these disorders and age-matched population-based random sample controls. METHOD: The Giessener Symptom Complaints Checklist assessed somatic complaints. The computerised Gottschalk-Gleser content analysis method assessed psychological state in 42 females with FM, 17 females with FD and 48 population-based, randomly selected control subjects. RESULTS: FM patients score higher on mutilation anxiety than FD and control subjects. FD patients had the highest score for death anxiety. Mutilation anxiety and low hope score identified FM patients (sensitivity 68%, specificity 81%, overall classification 75%), but only 19% of the variation in total somatic complaints could be predicted from these or other psychological state scores. In FD patients, however, death anxiety explained 59% of the variance in gastrointestinal complaints. INTERPRETATION: Psychological state was differentiated among the three groups. Mutilation anxiety may be a psychological marker of an underlying neurobiological vulnerability for FM or may represent a secondary long-term consequence of chronic illness. In FD, death anxiety is directly related to symptom complaints, suggesting a stronger etiological association between emotions and somatic complaints in this disorder.

Altered dopamine D2 receptor function in fibromyalgia patients: a neuroendocrine study with buspirone in women with fibromyalgia compared to female population based controls.

BACKGROUND: To what extent fibromyalgia belongs to affective spectrum disorders or anxiety spectrum disorders remains disputed. Buspirone induces a hypothermic response, which most likely is due to 5-HT(1A) autoreceptor stimulation, and growth hormone (GH) release, which probably is related to postsynaptic 5-HT(1A) receptor stimulation. The prolactin response to buspirone has been suggested to be mediated through dopamine (DA) antagonistic effects. OBJECTIVES: Based on the assumption that fibromyalgia is more strongly related to stress and anxiety than affective spectrum disorders, we hypothesized that compared to population controls, fibromyalgia patients should demonstrate an increased prolactin response (DA sensitivity) to buspirone challenge test, but no difference in hypothermic response or GH release (5HT sensitivity). METHOD: A 60-mg dose of buspirone was given orally to 22 premenopausal women with fibromyalgia and 14 age and sex matched healthy control subjects. Core body temperature, growth hormone and prolactin levels were analyzed at baseline and after 60, 90, and 150 min. RESULTS: Fibromyalgia patients showed an augmented prolactin response to buspirone compared to controls. Temperature and growth hormone responses did not differ from controls. CONCLUSIONS: Dopaminergic rather than serotonergic neurotransmission is altered in fibromyalgia, suggesting increased sensitivity or density of dopamine D(2) receptors in fibromyalgia patients. Stress and anxiety is an important modulator of dopaminergic neurotransmission. Our results suggest that fibromyalgia is related to anxiety and associated with disturbance in the stress response systems.

Factors explaining variance in perceived pain in women with fibromyalgia.

BACKGROUND: We hypothesized that a substantial proportion of the subjectively experienced variance in pain in fibromyalgia patients would be explained by psychological factors alone, but that a combined model, including neuroendocrine and autonomic factors, would give the most parsimonious explanation of variance in pain. METHODS: Psychometric assessment included McGill Pain Questionnaire, General Health Questionnaire, Hospital Anxiety and Depression Rating Scale, Eysenck personality Inventory, Neuroticism and Lie subscales, Toronto Alexithymia Scale, and Multidimensional Health Locus of Control Scale and was performed in 42 female patients with fibromyalgia and 48 female age matched random sample population controls. A subgroup of the original sample (22 fibromyalgia patients and 13 controls) underwent a pharmacological challenge test with buspirone to assess autonomic and adrenocortical reactivity to serotonergic challenge. RESULTS: Although fibromyalgia patients scored high on neuroticism, anxiety, depression and general distress, only a minor part of variance in pain was explained by psychological factors alone. High pain score was associated with high neuroticism, low baseline cortisol level and small drop in systolic blood pressure after buspirone challenge test. This model explained 41.5% of total pain in fibromyalgia patients. In population controls, psychological factors alone were significant predictors for variance in pain. CONCLUSION: Fibromyalgia patients may have reduced reactivity in the central sympathetic system or perturbations in the sympathetic-parasympathetic balance. This study shows that a biopsychosocial model, including psychological factors as well as factors related to perturbations of the autonomic nervous system and hypothalamic-pituitary-adrenal axis, is needed to explain perceived pain in fibromyalgia patients.