Evaluation of the effects of stress in cats with idiopathic cystitis

OBJECTIVE

To determine the effects of stress in cats with feline idiopathic cystitis (FIC) by evaluating bladder permeability, sympathetic nervous system function, and urine cortisol:creatinine (C:Cr) ratios during periods of stress and after environmental enrichment.

DESIGN

Prospective study.

ANIMALS

13 cats with FIC and 12 healthy cats.

PROCEDURE

Cats subjected to an acute-onset moderate stressor for 8 days received IV injections of fluorescein. Serum fluorescein concentrations were determined and compared with those of controls to evaluate bladder permeability, and urine C:Cr ratios were compared to evaluate function of the hypothalamic-pituitary-adrenal (HPA) axis. Plasma catecholamine concentrations were analyzed in a subset of cats. After 8 days of moderate stress, cats were moved to an enriched environment, and tests were repeated after 21 days.

RESULTS

Serum fluorescein concentrations were significantly higher in cats with FIC at all time points. In the cats in which plasma catecholamine concentrations were determined, concentrations of dihydroxyphenylalanine, norepinephrine, and dihyroxyphenylglycol were significantly higher in cats with FIC at all time points, whereas no differences in urine C:Cr ratio between groups were observed.

CONCLUSION AND CLINICAL RELEVANCE

Cats with FIC appeared to have altered bladder permeability, most notably during the period of initial stress. The increase in plasma dihydroxyphenylalanine concentration suggests that there may be stress-induced increase in the activity of tyrosine hydroxylase, which catalyzes the rate-limiting step in catecholamine synthesis. In contrast, no effects of stress on C:Cr ratios were observed, which suggests there was dissociation between the sympathetic nervous system and HPA-axis responses to stress.

Do blood pressure and heart rate responses to perceived stress vary according to endogenous estrogen level in women?

The results of experimental studies suggest that estrogen may blunt blood pressure responses to stress, but increase heart rate responses. We investigated whether within-person associations of perceived stress with blood pressure and heart rate during normal working life in 26 premenopausal and 7 postmenopausal women varied according to endogenous estrogen level. Each woman measured her own blood pressure and heart rate and completed a diary reporting perceived stress levels on six occasions on each of 2 working days. Premenopausal women were assessed once between days 4 and 6 of their menstrual cycle (low estrogen) and again between days 11 and 13 (high estrogen), and urine samples were taken to verify expected variation in estrogen level. Results showed that perceived stress was significantly positively associated with systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate in the group as a whole. This association did not differ according to menopausal status. There was no difference in the association of perceived stress with SBP or DBP in premenopausal women according to day of assessment, but heart rate reactivity to perceived stress was significantly higher on the high-estrogen day. Our findings thus provide evidence that heart rate responses to perceived stress during everyday working life vary according to estrogen level in premenopausal women, but no evidence that blood pressure responses to stress vary according to endogenous estrogen level in women.

A single session of emotional stress produces anxiety in Wistar rats

The sensorial stimulation arising from a physically stressed (PS) subject may produce emotional stress in a witnessing partner (WP). Both members of the pair develop functional changes. We tested changes in locomotor activity (crossing) and in the defensive burying test in WP, and PS adult male Wistar rats having been submitted to a single 10 min session in a two-compartment cage. During this session, the WP rats received auditory and olfactory stimulation coming from a PS pair submitted to unavoidable electric footshocks (1 mA, dc, 0.5s, 0.5c/s, 10 min). This experiment was replicated in other groups pre-treated with vehicle or diazepam, and their urine was collected and analyzed by the static Head-Space and Gas Chromatography-Mass Spectrometry (HS-GC/MS) techniques. The WP group displayed a significantly higher crossing [F((2,45))=4.31, P<0.01] and more cumulative burying time [F((2,22))=4.73, P<0.01] than the control or PS groups. Diazepam (1mg/kg) reverted these changes. Our results indicate that the conspecific sensorial communication coming from the PS group produces anxiety probably mediated by 2-heptanone, since the HS-GC/MS analyses showed the highest amount of 2-heptanone in the urine from the PS group [F((2,42))=5.17, P<0.009].

Urinary excretion of biopyrrins, oxidative metabolites of bilirubin, increases in patients with psychiatric disorders

Several authors have suggested that psychological stress induces the production of reactive oxygen species (ROS). Several studies have supported the idea that bilirubin exerts antioxidative effects in vivo, and it was reported psychological stress provokes bilirubin oxidation in vivo [Yamaguchi T., Shioji I., Sugimoto A., Yamaoka M., 2002. Psychological stress increases bilirubin metabolites in human urine. Biochem. and Biophys. Res. Commun. 293, 517-520]. We investigated whether the concentration of bilirubin oxidative metabolites (biopyrrins) is increased in urine from patients with psychiatric disorders. The concentration of biopyrrins in urine of 25 patients with psychiatric disorders (schizophrenia, 15; depression, 10) was compared with 96 healthy volunteers. The concentrations of biopyrrins, as measured by enzyme-linked immunosorbent assay, were normalized to the urinary concentration of creatinine. The concentration of biopyrrins in patients with psychiatric disorders (schizophrenia and depression) was significantly higher than that of healthy volunteers. In schizophrenia, biopyrrins levels correlated with scores of the Brief Psychiatric Rating Scale (BPRS), and in depression, biopyrrins levels correlated with scores of the Hamilton Depression Rating Scale (HAM-D). These finding suggest that psychotic states are associated with an increase in the oxidative metabolites of bilirubin in human urine.

[Poststressor change in attractiveness of mice odourgens]

It was shown, that under physiological conditions, intact noninbred mice or high-inbred mice-testers in reaction of preference-avoidance prefer volatile components secreted by mice of a genetically identical group. After exposure to stress factors, mice release with urine the volatile components, which are more preferable by testers than the volatile secretion of intact mice indepedently of the genotype of mice.

Vocal buffering of the stress response: exposure to conspecific vocalizations moderates urinary cortisol excretion in isolated marmosets

For many species, the presence of a significant social partner can lessen the behavioral and physiological responses to stressful stimuli. This study examined whether a single, individually specific, signature vocalization (phee call) could attenuate the physiological stress response that is induced in marmosets by housing them in short-term social isolation. Utilizing a repeated-measures design, adult marmosets (n=10) were temporarily isolated from their long-term pair mate and exposed to three conditions: signature vocalizations from the pair mate, phee calls from an unfamiliar opposite sex individual, or no auditory stimuli. Levels of urinary cortisol were monitored as a physiological indicator of the stress response. Urinary cortisol levels were also monitored, while subjects remained undisturbed in their home cages to provide baseline levels. Temporarily isolated marmosets showed significantly higher levels of urinary cortisol than undisturbed marmosets. However, the nature of the acoustic stimulus experienced during isolation led to differences in the excretion of urinary cortisol. Isolated marmosets exposed to a familiar pair mate's vocalization showed significantly lower levels of urinary cortisol than when exposed to unfamiliar marmoset vocalizations (P <0.04) or to no auditory stimuli (P <0.03). Neither the duration of pairing nor the quality of relationship in the pair (indexed by spatial proximity scores) predicted the magnitude of reduction in cortisol in the familiar vocalization condition. The results presented here provide the first evidence that a single, individually specific communication signal can decrease the magnitude of a physiological stress response in a manner analogous to the physical presence of a social partner, a process we term "vocal buffering."

Urinary catecholamine levels in daily life are elevated in women at familial risk of breast cancer

Recent experimental research has shown that women facing the chronic stress of being at familial risk of breast cancer have greater neuroendocrine reactivity responses to stressful laboratory tasks. Whether this enhanced stress response also occurs outside the laboratory under daily life conditions is unknown. In the present study, urinary epinephrine and norepinephrine excretion rates at work (e.g. 11:00 AM-3:00 PM), home (e.g. 6:00 PM-10:00 PM) and during sleep (e.g. 10:00 PM-6:00 AM) were compared between 73 employed women with family histories of breast cancer in first degree relatives (FH+; age=36.8+/-8.7) and 81 without such family histories (FH-; age=38.1+/-9.4). Differences in sympathetic adrenal medullary responses to an ordinary life stressor (work) were assessed in naturalistic settings. Repeated measures MANCOVA with family history group as a fixed factor, body mass index as a covariate and daily microenvironment (work, home and sleep) as a repeating factor were conducted to evaluate whether catecholamine excretion rates differed between FH+ and FH- groups. The results revealed that women with family histories of breast cancer had a higher rate of epinephrine excretion while at work (p<0.005). In addition, women in the FH+ group were also more reactive to the stress of work, showing a greater percentage of increase in both epinephrine and norepinephrine from sleep to work (p<0.05). The results also indicated that the chronic stress effects associated with a family history of breast cancer were moderated by BMI, such that their impact was more pronounced and apparent when women were not obese. These findings support the idea that the heightened neuroendocrine reactivity to experimental stressors in women at familial risk of breast cancer also occurs when women encounter stressors in ordinary life (work stress). Additional research to explore the health consequences of increased reactivity in women at familial risk of breast cancer, and perhaps in individuals at familial risk of other life-threatening disease, would appear warranted.

Two urinary catecholamine measurement indices for applied stress research: effects of time and temperature until freezing

Research on stress at work often involves the analysis of urinary adrenaline and noradrenaline. It is usually assumed that samples have to be cooled quickly and stored at refrigerator temperature before freezing. This is often difficult to achieve in field studies. This experimental study therefore tests the robustness of results when samples are not cooled immediately. Samples of 9 men and women, collected at 3 points in time, were immediately frozen, kept for a variable delay in a warm room, or stored in a refrigerator before freezing. Two indices were calculated: (a) the ratio of hormones to liquid volume, period of excretion, and body weight; and (b) the ratio of hormones to urinary creatinine. The reliability of high performance liquid chromatography analysis was satisfactory, as was the comparability of the 2 indices. Unfavorable storage up to 24 hr did not cause bacteria-driven decreases of catecholamines, regardless of storage temperature or sampling time. Results suggest high stability for at least 24 hr without cooling, provided the samples are immediately acidified. Cooling may therefore be handled less restrictively than has been assumed. The application of this research is to facilitate research in settings where samples are collected at different places, such as participants' homes or different workplaces.

Effect of metabolic cage housing on immunoglobulin A and corticosterone excretion in faeces and urine of young male rats

Six 8-week-old Sprague-Dawley rats were studied for 9 days divided into three periods of 3 days each: before transferral to metabolism cages, during metabolic cage housing and after return to their home cages. Faeces were collected daily when the animals were housed in their home cages and every 6 h when the animals were housed in metabolic cages during which time urine was also collected every 6 h. The rate of weight gain was slightly reduced during the 3 days in metabolic cages and the animals produced significantly larger amounts of faeces when housed in metabolic cages than when housed in their home cages. The total faecal excretion of corticosterone (nanograms excreted per hour per kilogram body weight) and immunoglobulin A (IgA) (milligrams excreted per hour per kg body weight) quantified by enzyme-linked immunosorbent assays (ELISAs) exhibited a clear diurnal rhythm in the metabolic cage. Urinary excretions of corticosterone and IgA also followed a clear diurnal cycle. The mean daily amounts of corticosterone excreted were not significantly affected by cage change and by housing in metabolic cages. However, the excretion of faecal IgA was significantly reduced during the 3 days after the period in metabolic cages. Taken together the results indicate that metabolic cage housing is mildly stressful for young adult male rats.

Urinary catecholamines and salivary cortisol on workdays and days off in relation to job strain among female health care providers

OBJECTIVES

This study examined the effects of psychosocial job strain on the excretion of neuroendocrine stress hormones (adrenaline, noradrenaline, and cortisol) on workdays and days off.

METHODS

Japanese female health care providers (N=16) filled out Karasek's job content questionnaire and had their neuroendocrine excretions (ie, urinary catecholamines and salivary cortisol) measured on a day off and on two workdays (one day shift and one night shift). After control for age and job experience as covariates, a repeated-measures analysis of variance was carried out.

RESULTS

Noradrenaline excretion was significantly greater over time in the high-strain group than in the low-strain group, and that of the high-demand group was significantly greater over time than that of the low-demand group. Adrenaline excretion did not significantly differ between the groups. The group with high supervisory support had significantly higher adrenaline excretion than the group with low supervisory support. The concentration of salivary cortisol on a dayshift was significantly lower, but marginally, in the high-strain group than in the low-strain group.

CONCLUSIONS

Psychosocial job strain is associated with greater noradrenaline excretion over time. This finding suggests unwinding sympathetic nervous activity. The low cortisol levels of the high-strain group may indicate circadian rhythm disturbance induced by job strain. Supervisory relationships may have a particular influence for the studied occupation because the participants had more administrative contact with supervisors than support at the worksite; therefore, supervisory support may increase adrenaline excretion.

Effect of stress on pregnancy outcome among women undergoing assisted reproduction procedures

BACKGROUND

This study was performed to examine the effect of stress on pregnancy outcome in women who underwent assisted reproductive technology (ART) procedures.

METHODS

In a controlled clinical study of healthy volunteers in an academic research environment, stress was measured subjectively by administering patient questionnaires and biochemically by examining urinary excretion of cortisol and 6-sulfatoxy-melatonin (6-SM), the primary metabolite of melatonin and a marker of peripheral stress response. A total of 42 women who underwent ART procedures during an 18-month period agreed to participate in the study and were enrolled consecutively. The women collected 24-hour urine specimens on the day after human chorionic gonadotropin administration and concurrently completed the State-Trait Anxiety Inventory questionnaire. We measured the cortisol and 6-SM levels in the urine collection for each of the 42 women and for 10 oocyte donors who served as controls. Pregnancy tests were performed 14 days after embryo transfer. Analysis of covariance was used to compare the relationship of stress ratings to urinary cortisol and 6-SM levels among the women who became pregnant, the women who did not, and the women who served as controls. Other variables were explored by performing chi2 analysis and Fisher's exact test.

RESULTS

Neither self-ratings of acute anxiety, nor total daily 6-SM value, nor cortisol levels were associated with pregnancy outcome in the ART procedures.

CONCLUSION

Biochemical markers of stress failed to support a deleterious effect of stress on pregnancy outcome in women who underwent ART procedures. Subjective measurement of stress levels did not differ between women who became pregnant and those who did not.

The association of subjective stress, urinary catecholamine concentrations and PC game room use and musculoskeletal disorders of the upper limbs in young male Koreans

The use of PCs can cause health problems, including musculoskeletal disorders (MSDs) of the upper limbs. This study was performed to investigate whether using PCs in PC game rooms may induce MSDs of the upper limbs. 284 young male Koreans were included. A self-administered, structured questionnaire was used to gather information about game room use, perceived subjective stress, and the symptoms related to MSDs. Urinary concentrations of epinephrine, norepinephrine, and dopamine were measured in spot urine. The symptom prevalence of MSDs of the upper limbs increased according to the increase of the duration of game room use. The intensity of perceived subjective stress showed a significant dose-response relationship with the frequency of MSDs symptoms in neck and shoulder areas. However, the urinary level of catecholamines was not significantly correlated with the symptom prevalence of MSDs in the upper limbs. These findings suggest that using PCs in game rooms produce physical stress on the upper limbs, strong enough to induce MSDs.

Daily psychosocial stressors and cyclic response patterns in urine cortisol and neopterin in a patient with systemic lupus erythematosus

This study investigated the complex biochemical responses to personally meaningful everyday stressors in a patient with systemic lupus erythematosus (SLE). For this purpose, a 52 year-old woman with SLE collected her entire urine for 56 days on a 12-h basis for the determination of cortisol as well as neopterin, a cellular immune parameter. Additionally, using questionnaires, daily notes and interviews, extensive psychosocial and psychological time-series data were collected every 12 h. Cross-correlational analyses of the resulting time-series revealed that stressful incidents were associated with cyclic fluctuations in both urine cortisol and urine neopterin. Specifically, whenever the patient anticipated a moderately stressful incident, urine cortisol initially increased 24 h before the incident and then decreased 12 h before the incident. Moderate stressors not anticipated by the patient were associated with an initial increase 24 h following the incident and then with a decrease after a total of 36 h. Moreover, stressors having to do with the patient's extramarital relationship were followed initially by a decrease in urine neopterin after 36 h and then by an increase after a total of 60 h. Our findings indicate that when investigating the relationship between psychosocial stressors and biochemical activity in SLE, appropriate consideration of the data's dynamic nature may be necessary to avoid flawed conclusions.

Time control, catecholamines and back pain among young nurses

OBJECTIVES

This study had two objectives. First, it addressed concern with the contribution of work stressors and resources to the development of back pain, over and above the influence of biomechanical work factors. Second, using recent models about the role of the sympathetic-adrenal medullar system in musculoskeletal problems as its basis, it tested whether low-back pain is associated with higher levels of catecholamines.

METHODS

Altogether 114 nurses filled out a questionnaire in their first year of practice and again one year later. In addition, in a subsample of 24 nurses studied intensively at follow-up, urinary catecholamines were assessed at noon, before the end of work, in the evening, and at corresponding times on a day off. Daily stressful experiences and daily mood were also recorded.

RESULTS

With control for baseline pain, biomechanical workload, and other potentially confounding variables, time control at the beginning of the study predicted low-back pain a year later. In the subsample, the epinephrine and norepinephrine levels were higher in those reporting more frequent episodes of back pain, the largest differences occurring at the end of work. In addition, control over stressful events at work was lower in this group.

CONCLUSIONS

Time control is a risk factor for low-back pain among nurses beyond the influence of physical work load. Low control at work may increase the activity of the sympathetic-adrenal medullar system, which seems to play an important role in the development of musculoskeletal pain.

Benzodiazepine premedication may attenuate the stress response in daycase anesthesia: a pilot study

PURPOSE

Patients undergoing daycase surgery suffer from varying degrees of fear and anxiety. There is conflicting evidence in the literature regarding the benefit of benzodiazepine premedication in daycase surgery. We carried out a prospective, double-blind, randomized pilot study investigating the effect of benzodiazepine premedication on the stress response in patients undergoing daycase anesthesia and surgery.

METHODS

Group I (n = 16) received diazepam 0.1 mg*kg(-1) orally 60 min preoperatively; Group II (n = 15) received diazepam 0.1 mg*kg(-1) orally 90 min preoperatively; Group III (n = 30) received a placebo. The stress response was measured by analyzing urinary catecholamine and cortisol levels and by scoring anxiety levels using state-trait anxiety inventory (STAI) scores and visual analogue scores (VAS).

RESULTS

Anxiety scores (VAS and STAI scores) were not different between groups. We found a statistically significant reduction in urinary cortisol and noradrenaline levels in the groups receiving diazepam vs placebo.

DISCUSSION

The reduction in stress hormones following diazepam premedication, in patients undergoing daycase surgery may support the role for benzodiazepine premedication in this setting. However, further studies are warranted to determine the clinical significance of these findings.

Multifactorial analysis of the aetiology of craniomandibular dysfunction in children

OBJECTIVES

It is generally accepted that the aetiology of craniomandibular dysfunction (CMD) is multifactorial. Different types of malocclusion, oral parafunctions especially bruxism, trauma of the mandible or temporomandibular joint (TMJ) and emotional stress are known aetiologic factors. Research has been conducted into the relationship between each of these aetiologic factors and the signs and symptoms of CMD. However, such an approach does not control for the simultaneous effect of other factors responsible for the development of the dysfunction. The purpose of this study was to investigate the effect of each aetiologic factor on the signs and symptoms of CMD in children, controlling for the effect of all other known factors by means of a multifactorial analysis.

METHODS

A sample of 314 children, aged 6-8 years, was examined clinically for signs of CMD and morphologic and functional malocclusion. Symptoms of CMD and oral parafunctions were recorded by the same investigator in an interview. Emotional stress was measured through urinary catecholamines including epinephrine, norepinephrine and dopamine, detected in a 24-h urine sample, using high performance liquid chromatography. A questionnaire was distributed to the parents to collect information regarding socioeconomic factors and the history of dentofacial injuries. A logistic multiple regression was carried out to estimate the partial effect of each aetiologic factor. A 95% probability level was used.

RESULTS

Posterior crossbite with lateral shift significantly affected the probability of child developing deviation of the mandible on opening. Similarly, posterior crossbite and epinephrine had a significant impact on TMJ tenderness, overjet had an effect on clicking, clenching and biting of objects had an effect on muscle tenderness, and lip/cheek biting influenced dysfunctional opening. Of the symptoms reported, pain on wide opening was affected significantly by lip/cheek biting.

CONCLUSION

On the basis of these results, it can be suggested that parafunctional and some structural and psychological factors may increase the probability of the child developing the signs and symptoms of CMD.

Psychological stress increases bilirubin metabolites in human urine

Some authors have suggested that psychological stress induces the production of reactive oxygen species (ROS). Some studies have supported that bilirubin exerts anti-oxidative effects in vivo. However, it is not known whether ROS induced by psychological stress provoke bilirubin oxidation in vivo. We investigated if the concentration of bilirubin oxidative metabolite (BOM), a bilirubin oxidative metabolite, increased in urine from subjects exposed to psychological stress. Sixty healthy male volunteers working in a pharmaceutical company were divided into a Group I which did not attend a conference, a Group II which attended a conference but did not deliver a speech, and a Group III which attended a conference and delivered speeches in the presence of the company executives. Subjective stress was scored (self-rating score) after subjects in Group III delivered their speeches at the conference. Urine was collected on the next day. The BOM concentrations, as measured by enzyme-linked immunosorbent assay, were normalized to the urinary concentration of creatinine. The concentration of BOM in Group III was significantly higher compared to that in Groups I and II (p<0.01 and p<0.05, respectively). Furthermore, in Group III, the concentration of BOM correlated with the self-rating stress score (r=0.53, p<0.01). These findings suggest that emotional stimuli are associated with an increase in the oxidative metabolites of bilirubin in human urine, and that BOMs could be useful markers of psychological stress.

Differences in urinary stress hormones in male and female nurses at different ages

AIM

The aim of this study was to assess the levels of urinary stress hormones in male and female nurses and to determine their contribution to sex-determined health outcomes. RATIONALE/BACKGROUND: While the use of questionnaires have shown that there is a high degree of stress in health care workers, these results are inconclusive. In this study a more objective approach was used by assessing the levels of urinary stress hormones, adrenaline, noradrenaline and cortisol. In premenopausal women oestrogen may attenuate sympathetic nervous system activity and the secretion of adrenaline and cortisol and therefore lower the stress response and incidence of stress-related illnesses.

METHODS

Three hundred and fifteen nurses of both sexes were separated into two age groups, 20-40 and 45-60 years, and for postmenopausal women into those taking or not taking hormone replacement therapy (HRT). Early morning urine sample were collected and stress hormones determined by high performance liquid chromatography (HPLC).

RESULTS

Urinary cortisol, adrenaline and noradrenaline levels were all increased with age in both sexes, with a greater difference in the younger age group compared with the older group. These hormones were lower in premenopausal women compared with male nurses of similar age. The difference between the sexes in the high age group was less compared with the lower one. Postmenopausal women on HRT had lower levels of these hormones.

CONCLUSION

The age-related changes were surprising but may be because of higher stress levels in the older groups of both sexes. However, the gender difference supports the view that oestrogen reduces sympathetic activity and the secretion of cortisol and adrenaline. HRT reduces the stress response and therefore may have additional benefits by reducing the level of stress-related illnesses. These results were surprising but may suggest that oestrogen reduces the stress response in women and therefore offers protection against stress-related disorders.

[The influence of daily psychosocial stressors and associated emotions on the dynamic course of urine cortisol and urine neopterin in systemic lupus erythematosus: Experience taken from two "integrative single-case studies"]

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by flare-ups, the cause of which is unknown. According to new stress concepts, two "integrative single-case studies" have been conducted in order to gather evidence about whether daily stressful incidents and associated emotions interfere with the dynamics of urine cortisol and urine neopterin in SLE. Patients under study collected their urine at home, for a period of at least 50 days, on a daily basis, divided into day and night urine. Additionally, patients filled out questionnaires twice a day to determine their emotional state, life style and disease activity. Each week, patients were examined clinically and interviewed to identify the past week's stressors using the Incidents and Hassles Inventory (IHI, Brown and Harris). Statistical analysis of the serial data was performed using time-series analysis according to Box and Jenkins. In both "integrative single-case studies" we were able to demonstrate that stressful incidents predicted an increase in urine neopterin 36 hours (Case 1) to 60 hours (Case 2) later (p < 0.05). Additionally, in Case 1 the neopterin levels were highly associated with stress resulting from the weekly examinations and interviews. Furthermore, in Case 2 it turned out that depending on their predictability stressful incidents were preceded by a decrease in urine cortisol 12 hours earlier or were followed by a decrease in urine cortisol 36 hours later. And finally, emotional irritation was highly correlated with the course of urine-neopterin. In Case 2 irritation led to an increase in urine neopterin 84 hours later. There were no clinical signs of SLE during both prospective studies. In conclusion, our results validate the idea of "integrative single-case studies" as a new "bio-psycho-social" approach in psychoneuroimmunology. Further studies with SLE patients as well as with healthy probands will be necessary in order to both strengthen and generalize these results.

[Cortisol in night-urine: Introduction of a research method in psychoneuroendocrinology]

Cortisol is one of the major parameters investigated in psychoneuroendocrinological research, but the methods employed for sample collecting are often unsatisfactory. A suitable method of sample collection should allow for the integrative assessment of long-term changes of the HPA-system, should be non-invasive, and should not exceed the subject's compliance. The assessment of cortisol in night-urine fulfils these demands; although this method has been occasionally employed, it has not yet been described systematically. For the first time a detailed description is given here that allows for a standardized replication. In ten previous studies and three investigations of our own this method has been successfully applied to detect changes in the cortisol excretion of patients with endocrinological and psychiatric disorders as well as in subjects under conditions of psychosocial stress. The determination of cortisol in night-urine represents an ideal method for the assessment of changes in the basal HPA-activity in numerous areas of psychoneuroendocrinological research, e.g. field and screening studies in natural environment, clinical studies in psychiatry and especially follow-up studies in psychotherapy research.

The West London Schools Study: the effects of chronic aircraft noise exposure on child health

BACKGROUND

Previous field studies have indicated that children's cognitive performance is impaired by chronic aircraft noise exposure. However, these studies have not been of sufficient size to account adequately for the role of confounding factors. The objective of this study was to test whether cognitive impairments and stress responses (catecholamines, cortisol and perceived stress) are attributable to aircraft noise exposure after adjustment for school and individual level confounding factors and to examine whether children exposed to high levels of social disadvantage are at greater risk of noise effects.

METHODS

The cognitive performance and health of 451 children aged 8-11 years, attending 10 schools in high aircraft noise areas (16 h outdoor Leq > 63 dBA) was compared with children attending 10 matched control schools exposed to lower levels of aircraft noise (16 h outdoor Leq < 57 dBA).

RESULTS

Noise exposure was associated with impaired reading on difficult items and raised annoyance, after adjustment for age, main language spoken and household deprivation. There was no variation in the size of the noise effects in vulnerable subgroups of children. High levels of noise exposure were not associated with impairments in mean reading score, memory and attention or stress responses. Aircraft noise was weakly associated with hyperactivity and psychological morbidity.

CONCLUSIONS

Chronic noise exposure is associated with raised noise annoyance in children. The cognitive results indicate that chronic aircraft noise exposure does not always lead to generalized cognitive effects but, rather, more selective cognitive impairments on difficult cognitive tests in children.

Cardiovascular reactivity to and renal impact of stress and exercise: effects of bisoprolol

The orthosympathetic nervous system is involved in the pathogenesis of essential hypertension. In this study, we carried out tests of sympathetic stimulation using successfully an isometric exercise and a psychological stress. The efficacy of the two tests in 10 normotensive patients (NTs) was assessed by a significant increase in blood pressure and heart rate and a significant increase in metanephrine urinary excretion. These tests, repeated 2 months later, were perfectly reproducible in NTs. The cardiovascular response during exercise and stress was significantly higher in 10 hypertensive patients (HTs) than in NTs. At rest, urinary norepinephrine excretion was significantly higher in HTs. In contrast to NTs, stress in HTs significantly increased urinary excretion of epinephrine and norepinephrine, whereas exercise failed to increase urinary catecholamine excretion in both groups. In HTs, both tests induced an increase in microalbuminuria. Among functional renal parameters, only proximal sodium reabsorption (measured by lithium clearance) was significantly lower in HTs than in NTs, compensated by a higher distal reabsorption. In HTs, 2 months of treatment with bisoprolol reduced rest and peak heart rate and blood pressure, but failed to reduce blood pressure reactivity to the orthosympathetic stimulation. Proximal sodium reabsorption at rest was normalized by the treatment. Bisoprolol was also able to reduce microalbuminuria during the 24 h and in the rest period preceding the test, but the same percent increase was observed during tests.

Urine catecholamine concentrations and psychophysical stress in elite tennis under practice and tournament conditions

BACKGROUND

The purpose of the study was to specify and define the differences of psychophysical stress in elite tennis players under practice and tournament conditions.

METHODS

Basal, pre- and postcompetition urine samples of 26 nationally ranked players (NR) were analysed for concentrations of epinephrine (EPI) and norepinephrine (NE) under practice (P) and tournament conditions (T). Results were completed by the values obtained from two internationally ranked players (IR) competing in 6 (player A) and 5 (player B) Davis-Cup matches, respectively.

RESULTS

In NR, pre- and postcompetition concentrations for EPI were significantly higher under tournament conditions (T: 1.33+/-0.65 and 3.66+/-2.51 microg/100 mg creatinine vs P: 0.61+/-0.39 and 0.97+/-0.59 microg/100 mg creatinine). The NE/EPI ratio showed significantly inverse results (T: 3.53+/-1.87 and 3.58+/-1.59 vs P: 8.08+/-6.99 and 10.03+/-6.58), whereas the concentration of NE did not differ between the two conditions. Significant correlations were found between the level of perceived nervousness (ten-point-likert scale) and the postcompetition concentration of EPI (r=0.491, p<0.05) and the NE/EPI ratio (r=-0.595, p<0.01). Players who felt affected by nervousness in their performance outcome showed significantly lower NE/EPI ratios (2.73+/-1.44 vs 4.49+/-2.54, p<0.05). The Davis-Cup-Players showed intra-individually constant but inter-individually different concentrations of EPI (A= 2.2+/-0.5 vs B= 7.0+/-0.8 microg/100 mg creatinine), NE (A= 7.4+/-2.2 vs B= 15.5+/-3.2 microg/100 mg creatinine) and the ratio of NE/EPI (A= 3.7+/-2.2 vs B= 2.2+/-0.7).

CONCLUSIONS

In tennis tournaments, sympathetic activity is increased due to a higher psychological stress which may impair performance. Practical efforts should focus on psycho-regulative methods and psychophysical regeneration for players dealing with a chronic sympathetic hyper-activation.