Effect of rest on physicians' performance in an emergency department,objectified by electroencephalographic analyses and psychometric tests

OBJECTIVE: The aim of the field study was to objectify physicians' vigilance, well-being, and cognitive performance in the course of 24-hr shifts with and without afternoon rest. SUBJECTS, SETTING, AND DESIGN: Eleven residents (four women, seven men; age, 33.5 +/- 4.7 yrs) were observed when doing two regular 24-hr shifts at the emergency department (randomized crossover design): one without rest, the other with a period of rest in the early afternoon (duration, 2:31 +/- 1:04 hrs) and the opportunity of having a nap (duration, 1:07 +/- 0:26 hrs, n = 6). Electroencephalography and psychometric tests were carried out at 8 am and at midnight. MEASUREMENTS: Measurements included subjective perception of workload, stress, and sleeping behavior; computer-analyzed electroencephalography; adjective checklist (Eigenschaftsw?rterliste 60 S, a self-rating scale); complex reaction time test; Pauli test (number of calculations during 3 mins); and numerical memory test. RESULTS: Electroencephalographic analyses showed a significant decrease in alpha power and a significant increase in beta power in the evening as compared with the morning on both days. The nocturnal increase observed in delta activity was significantly less pronounced in duties with rest than in duties without rest. Physicians felt deactivated at night. The Eigenschaftsw?rterliste 60 S indicated deactivation at night and a rest-induced activation in the subgroup that had taken the opportunity to sleep in the afternoon. Psychometric tests did not show any significant differences, neither between performance in the morning and evening nor between results with and without rest. CONCLUSION: As expected, electroencephalographic recordings showed nocturnal deactivation and a vigilance-promoting effect of the afternoon rest. These objective findings were in accordance with the results derived from self-rating scales. On the other hand, in short-lasting psychometric tests, performance was found unchanged after 16 hrs of routine work. In further studies, a discrimination between resting periods with and without sleep will be important.     

Short-term propofol infusion as an adjunct to extubation in burned children

Children who require intubation as a component of their burn management generally need heavy sedation, usually with a combination of opiate and benzodiazepine infusions with a target sensorium of light sleep. When extubation approaches, the need for sedation to prevent uncontrolled extubation can conflict with the desire to lighten sedation enough to ensure that airway protective reflexes are strong. The several hours' half-life of these medications can make this period of weaning challenging. Therefore, the hours preceding extubation are among the most difficult in which to ensure safe adequate sedation. The pharmacokinetics of propofol allow for the rapid emergence of a patient from deep sedation. We have had success with an extubation strategy using short-term propofol infusions in critically ill children. In this work, children were maintained on morphine and midazolam infusions per our unit protocol, escalating doses as required to maintain comfort. Approximately 8 hours before planned extubation, these infusions were decreased by approximately half and propofol infusion added to maintain a state of light sleep. Extubation was planned approximately 8 hours later to allow ample time for the chronically infused opiates and benzodiazepines to be metabolized down to the new steady-state level. Thirty minutes before planned extubation, propofol was stopped while morphine and midazolam infusions were maintained at the reduced level. When the children awakened from the propofol-induced state of light sleep, they were extubated while the reduced infusions of morphine and midazolam were maintained. These were subsequently weaned slowly, depending on the child's need for ongoing pain and anxiety medication, per our unit protocol to minimize the incidence of withdrawal symptoms. Data are shown in the text as mean +/- standard deviation. These 11 children (eight boys and three girls) had an average age of 6.6 +/- 5.6 years (range, 1.2-13 years), average weight of 36.9 +/- 28.7 kg (range, 9.3-95 kg), and burn size of 43 +/- 21.4% (range, 10-85%). Three children had sustained scald burns and eight had flame injuries with associated inhalation injury. They had been intubated for an average of 12.7 +/- 10.9 (range, 2-33 days). Morphine infusions immediately before the initiation of propofol averaged 0.26 +/- 0.31 mg/kg/hour (range, 0.04-1.29 mg/kg/hr) and midazolam averaged 0.15 +/- 0.16 mg/kg/hr (range, 0.06-0.65 mg/kg/hr). Morphine infusions after beginning propofol and at extubation averaged 0.16 +/- 0.16 (range, 0.04-0.65 mg/kg/hr) and midazolam averaged 0.09 +/- 0.08 mg/kg/hr (range, 0.02-0.32 mg/kg/hr). Propofol doses after initial titration during the first hour of infusion averaged 3.6 +/- 2.9 mg/kg/hr (range, 0.4-8.1 mg/kg/hr). Nine of the 11 children (82%) were successfully extubated on the first attempt. Two required reintubation for postextubation stridor 2 to 6 hours after extubation but were successfully extubated the next day after a short course of steroids, again using the same propofol technique. All were awake at extubation and went on to survive. Morphine and midazolam infusions were gradually weaned, and there were no withdrawal symptoms noted. Although prolonged (days) infusions of propofol have been associated with adverse cardiovascular complications in critically ill young children and should probably be avoided, short-term (in hours) use of the drug can facilitate smooth extubation.     

Correlates and influences of taking an afternoon nap on nocturnal sleep in Chinese elderly: A qualitative study

Taking afternoon naps is common among elderly people, but the information about napping from qualitative viewpoints is limited. This study aimed to describe napping experience from the perspectives of Chinese elderly, specifically on nap taking correlates and its influences on nocturnal sleep. Data were gathered via individual in-depth interviews with 50 Chinese elderly in Taiwan. The majority of the nappers napped for 1–2 hours between 12 PM and 1 PM. Nap promoting factors included “belief in afternoon nap taking benefits,” “nothing to do,” “low energy level,” “compensation -for disturbed sleep” and “extreme weather.” Nap taking (>1?hr.) was found to be associated with delay of the onset of sleep, reduction of sleep duration, and light sleep. Short afternoon napping (<1 hour) is recommended for the elderly. Future research should determine the direction of the causative association between afternoon nap-taking and nocturnal sleep.     

Preterm infant temperature circadian rhythm: possible effect of parental cosleeping

The purpose of this study was to describe the circadian rhythm of abdominal skin temperature and explore factors related to the timing of circadian rhythm acrophase. Thirty-four preterm infants (gestational age 26 to 33 weeks) were studied in the home environment at 44 to 46 weeks postconceptional age. Insulated abdominal skin was monitored continuously, and parents recorded sleep/wake activity over a 24-h period. Circadian rhythm was analyzed using cosinor analysis. Using MANCOVA, the effects of cosleeping, feeding method, night feeding, hospital stay, time home, and illness on acrophase were determined. Infants demonstrated evidence of developing circadian rhythm of temperature. Cosleeping and length of hospital stay were significantly related to acrophase. The mean acrophase for cosleeping infants was 07:44 (95% confidence interval = 05:12, 11:08), whereas that for non-cosleeping infants was 22.05 (95% confidence interval = 17:31, 01:42). Proximity with parents during nighttime hours may serve to entrain preterm infant circadian rhythm.     

Sleep health in young children living with socioeconomic adversity

Racially and ethnically diverse young children who live with socioeconomic adversity are at high risk for sleep deficiency, but few behavioral sleep interventions (BSIs) are tailored to their needs. To support the future development of a feasible, acceptable, and culturally relevant sleep intervention, we conducted a community-engaged, mixed-methods study with 40 low-income, racially, and ethnically diverse parents to describe sleep characteristics, sleep habits, and parental sleep knowledge of their 6–36-month-old children and to examine the associations between children's sleep characteristics and sleep habits. This report presents quantitative data from this mixed-methods study. We measured objective (actigraphy) and parent-reported sleep (Brief Infant Sleep Questionnaire) characteristics, sleep habits at bedtime, sleep onset, and during night awakenings, parental sleep knowledge, psychological function (Brief Symptom Inventory), and parenting stress (Parenting Stress Index). Children had low sleep duration (537.2 ± 54.7 nighttime and 111.2 ± 29.8 nap minutes), late bedtimes (22:36 ± 1.5 hr), and high bedtime variability (mean squared successive difference = 3.68 ± 4.31 hr) based on actigraphy. Parental knowledge about sleep recommendations was limited. Sleep habits before bedtime, at sleep onset, and during night awakenings were varied. Sixty-five percent of parents reported co-sleeping. Feeding near bedtime or during the night was associated with later bedtimes, more fragmented sleep, and increased bedtime variability. These findings suggest the need for BSIs to support earlier bedtimes and improve sleep duration and continuity by addressing modifiable behaviors. Tailored BSIs that consider socioecological influences on the development of sleep habits are needed.     

Fatigue and stress sensitivity of physicians after 16 hours on duty at the emergency department

In addition to their 40-hour working week (Mon-Fri, 8 a.m.-4 p.m.) residents at the emergency department of the General Hospital of Vienna have to do approximately six 24-hour duties. The reasons for conducting the present field study were physicians' complaints about tiring night duties. 11 residents (4 women, 7 men; aged between 28 and 43 years, x = 33.5 +/- 4.9 years; working at the emergency department for 4-50 months, x = 31 +/- 20 months) were tested on an ordinary working day at 9 a.m. and midnight. Self-rating concerning sleep duration, perception of stress and workload on the days of the investigations were found to be representative of other prolonged duties. Subjects reported a usual nocturnal sleep duration of only 6-7 hours. Stress was regarded as moderate by most of the volunteers. Blood pressure and pulse rates did not show diurnal changes. Generally, residents felt significantly (p < 0.01) less awake at night than in the morning, but reported only slight vegetative and somatic stress reactions or annoyances as assessed by the Fahrenberg self-rating scale. Interindividual differences were found; residents who had been working at the emergency department for a longer period experienced a more pronounced impairment. Further studies are required in order to objectify a nocturnal decrease in vigilance (by means of computer-assisted EEG) and to evaluate potential performance deficits (by means of psychometric tests).     

The caffeine CO2 breath test: dose response and route of N-demethylation in smokers and nonsmokers

The optimal conditions for performing the caffeine CO2 breath test (CBT) were investigated in smokers and nonsmokers. Caffeine labeled with 13C or 14C in all three (1, 3, and 7) methyl groups or specifically in the 1-, 3-, or 7-methyl groups were orally administered to healthy adults and the expiration of labeled CO2 was measured for 8 or 24 hr. The absolute rate of labeled CO2 excretion from trilabeled caffeine was proportional to the dose up to 3 mg/kg in all subjects. In smokers, the rate of labeled CO2 excretion averaged twice that in nonsmokers at all doses. A correlation was observed between the 2-hr cumulative CO2 excretion from trilabeled caffeine and the apparent oral metabolic clearance rate (MCR) of caffeine (R = 0.90). Monolabeled CBTs in smokers and nonsmokers demonstrated that 80% +/- 4% of labeled CO2 expired in the breath during the first 2 hr of a trilabeled CBT was derived from the 3 position; at 6 to 8 hr equal amounts were derived from the 3 and 7 positions. Little N-demethylation was observed from the 1 position at any time during the 8-hr test. The results indicate that the 2-hr cumulative excretion of labeled CO2 could be used to accurately predict the metabolic clearance rate of caffeine is the best CBT parameter for detecting the effect of smoking on caffeine N-demethylation. The data suggest that the primary routes of caffeine metabolism are 3-N-demethylation and ring hydroxylation and confirm that caffeine metabolites are N-demethylated primarily in the 3 and 7 positions.     

Modulation of glucose regulation and insulin secretion by circadian rhythmicity and sleep.

To define the roles of circadian rhythmicity (intrinsic effects of time of day independent of the sleep or wake condition) and sleep (intrinsic effects of the sleep condition, irrespective of the time of day) on the 24-h variation in glucose tolerance, eight normal men were studied during constant glucose infusion for a total of 53 h. The period of study included 8 h of nocturnal sleep, 28 h of continuous wakefulness, and 8 h of daytime sleep. Blood samples for the measurement of glucose, insulin, C-peptide, cortisol, and growth hormone were collected at 20-min intervals throughout the entire study. Insulin secretion rates were derived from C-peptide levels by deconvolution. Sleep was polygraphically monitored. During nocturnal sleep, levels of glucose and insulin secretion increased by 31 +/- 5% and 60 +/- 11%, respectively, and returned to baseline in the morning. During sleep deprivation, glucose levels and insulin secretion rose again to reach a maximum at a time corresponding to the beginning of the habitual sleep period. The magnitude of the rise above morning levels averaged 17 +/- 5% for glucose and 49 +/- 8% for calculated insulin secretion. Serum insulin levels did not parallel the circadian variation in insulin secretion, indicating the existence of an approximate 40% increase in insulin clearance during the night. Daytime sleep was associated with a 16 +/- 3% rise in glucose levels, a 55 +/- 7% rise in insulin secretion, and a 39 +/- 5% rise in serum insulin. The diurnal variation in insulin secretion was inversely related to the cortisol rhythm, with a significant correlation of the magnitudes of their morning to evening excursions. Sleep-associated rises in glucose correlated with the amount of concomitant growth hormone secreted. These studies demonstrate previously underappreciated effects of circadian rhythmicity and sleep on glucose levels, insulin secretion, and insulin clearance, and suggest that these effects could be partially mediated by cortisol and growth hormone.     

Acute sleep deprivation is associated with increased electrocardiographic P-wave dispersion in healthy young men and women

Background: Sleep deprivation (SD) is associated with worse cardiovascular outcome including mortality. Prolonged P-wave duration and P-wave dispersion (Pd) are known to represent inhomogeneous conduction of sinus impulses and are known to be electrophysiologic predictors of atrial fibrillation. Pd in normal subjects has been reported to be influenced by the autonomic tone. Because autonomic tone is affected by sleep and sleep duration, we evaluated the effect of acute SD on P-wave duration and Pd in healthy young adults and whether the effect was gender selective.
Methods : We obtained electrocardiograms of 37 healthy young volunteers (age: 28.45 ± 7.97; 11 women) after a night of regular sleep and repeated after a night with sleep debt. We measured minimum and maximum P-wave durations (Pmin, Pmax) and Pd in milliseconds.
Results : Average sleep time of the subjects were 7.7 ± 0.8 hours during regular sleep and 1.7 ± 1.6 hours during a night of sleep debt (P < 0.001). Subjects had significantly lower values of Pmin in milliseconds after a night of sleep debt when compared to regular sleep (65.13 ± 8.03 vs 74.86 ± 10.95; P < 0.001), whereas they had significantly higher values of Pmax and Pd (102.16 ± 9.46 vs 95.13 ± 11.21; P < 0.001 and 37.02 ± 8.11 vs 20.27 ± 11.42; P < 0.001, respectively). In Pearson's correlation analysis Pmin was positively and Pmax and Pd were negatively correlated with sleep time (P < 0.001, r = 0.465; P = 0.003, r =−0.336 and P < 0.001, r =–0.698 respectively). Effect of SD on P-wave duration and Pd was similar for both men and women.
Conclusions : In conclusion, prolongation of Pmax and Pd in acute SD suggests that acute SD might contribute to development and/or recurrence of atrial fibrillation.     

Effect of zolpidem on sleep in women with perimenopausal and postmenopausal insomnia: a 4-week, randomized, multicenter, double-blind, placebo-controlled study

BACKGROUND: Although most adults in the United States obtain less sleep than they need, women report more sleep deprivation throughout their lifetime than do men. The prevalence of self-reported sleep difficulty increases as women make the transition from the premenopausal to the postmenopausal period. OBJECTIVE: The purpose of this study was to assess the clinical efficacy and safety of zolpidem as a treatment for insomnia in perimenopausal and postmenopausal women. METHODS: Women who were perimenopausal or postmenopausal for >or=6 months, who had developed insomnia in conjunction with menopausal symptoms, and who had difficulty maintaining sleep or had nonrestorative sleep for >or=6 months were eligible for this 4-week, multicenter study. Sleep maintenance difficulty had to occur an average of >or=3 nights per week and had to be accompanied by >or=2 nocturnal hot flashes, hot flushes, or night sweats. Patients were randomized in a double-blind fashion to 1 of 2 treatment groups--zolpidem 10 mg or placebo. Capsules were provided in weekly blister cards, and patients were instructed to take 1 capsule each night at bedtime. Patients recorded estimates of their sleep quality and quantity and daytime functioning on daily morning and evening questionnaires, and made weekly global assessments of sleep. RESULTS: The study included 141 women (mean age +/- SD, 50.8 +/- 4.5 years; age range, 39-60 years). Increases in reported total sleep time were significantly greater in the zolpidem group than in the placebo group (P < 0.01) for each treatment week. Wake time after sleep onset and number of awakenings decreased significantly in the zolpidem group compared with the placebo group (P < 0.05). Each week, approximately twice as many patients in the zolpidem group as in the placebo group reported improved sleep (P < 0.001 for each week). The improvement in sleep-related difficulty with daytime functioning was significantly greater in the zolpidem group than in the placebo group (P < 0.05). The effects of zolpidem did not diminish with the duration of treatment. CONCLUSIONS: Zolpidem 10 mg/d was effective and well tolerated in the treatment of menopause-related insomnia in perimenopausal and postmenopausal women.     

Narcolepsy update

Narcolepsy, a disorder of excessive daytime sleepiness that affects more than 125,000 people in the United States, is technically defined as a daytime mean sleep latency (time elapsed before falling asleep) of less than 5 minutes in conjunction with verification of rapid eye movement sleep in at least two of five daytime nap periods. Cataplexy, hypnagogic hallucinations, and sleep paralysis are frequently associated with narcolepsy. Currently, overnight polysomnography and multiple sleep latency testing in a sleep disorders laboratory are used to diagnose narcolepsy. Standard pharmacologic therapy consists of the judicious use of stimulants to improve alertness and the administration of tricyclic and other antidepressant drugs to suppress cataplexy. In addition, good sleep hygiene (a regular sleep-wake schedule, an adequate amount of sleep at night, and scheduled daytime naps) is essential for optimal management of this disorder. Patient and family education about narcolepsy and its treatment is also important. Even with use of the best available treatment regimens, many patients with narcolepsy have substantial vocational and social impairments.     

Assessment of heart rate circadian rhythms in paroxysmal atrial fibrillation

Heart rate (HR) variations during night sleep and in the early predawn period in healthy subjects and patients with paroxisms of artrial fibrillation were used to assess HR circadian rhythms. Daily ECG monitoring was performed in 19 healthy subjects (mean age 36.0 +/- 7.05 years) and patients with paroxisms of atrial fibrillation (mean age 55.15 +/- 3.91 years). In healthy subjects, HR responsiveness during night sleep and in the early predawn hours was more prominent than in patients with paroxisms of atrial fibrillation. The number of HR spikes at night was 20.42 +/- 3.73 and 14.23 +/- 2.8 (p < 0.001) and one hour before waking 3.74 +/- 1.33 and 1.92 +/- 1.04 (p < 0.001) respectively; premorning activation coefficient was 0.19 +/- 0.007 and 0.13 +/- 0.007 (p < 0.05). It is concluded that HR responsiveness during the night sleep and the early predawn period in healthy subjects is higher than in patients with paroxisms of articular fibrillation. The number of HR spikes at night and one hour before waking as well as premorning activation coefficient can be used to assess RH circadian rhythms.     

Relationships among sleep dimensions and factors that impair sleep after cardiac surgery

Factors associated with the attempted length, disturbance, effectiveness, and nap supplementation of sleep were analyzed in 97 patients recovering from cardiac surgery a few days before hospital discharge. Patients rated sleep for the prior night and factors that impaired their sleep after transfer from the critical care unit. The group averaged little sleep, with moderate disturbance and effectiveness and low nap supplementation. The disturbance, effectiveness, and attempted length of sleep were associated with an inability to perform their usual routine before sleep, inability to get comfortable, pain, noises, procedural care, and an unfamiliar bed. Patients encounter difficulties with sleep, even near discharge from the hospital. Interventions should be tested to mitigate specific factors that affect selected dimensions of sleep. © 1996 John Wiley & Sons, Inc.     

Correction of sleep disorders and efficacy of antihypertensive monotherapy in elderly patients: use of ivadal]

AIM: To assess effects of ivadal (zolpidem) on arterial pressure (AP) in the cycle sleep-awake in aged patients with insomnia who have failed hypotensive monotherapy with different drugs, i.e. whose AP remained abnormal at night. MATERIALS AND METHODS: The trial included 25 aged patients (17 females, 8 males, mean age 66.4 +/- 3.7 years) with isolated systolic arterial hypertension (AH) of the first-second degree (WHO classification, 1999) and insomnia. AH duration averaged 8.7 +/- 3.7 years. All the patients have received antihypertensive monotherapy. As shown by the initial 24-h monitoring, patients with elevated night AP had significantly lower mean score by the questionnaire "Subjective Sleep Characteristics" and more frequently suffer from insomnia. These patients were given a hypnotic drug ivadal (zolpidem) in a single daily dose 5 mg in the evening for 10 days. On the treatment night 10 monitoring of AP was repeated. RESULTS: Ivadal treatment has significantly improved all the subjective parameters of sleep and 24-h AP profile, lowered sleep and awake AP. CONCLUSION: Ivadal treatment raises efficacy of a hypotensive monotherapy in aged patients with isolated systolic AH and insomnia.     

Sleep parameters in patients using pacemakers with sleep rate function on

INTRODUCTION: The cardiovascular system (CVS) is heavily influenced by the autonomic nervous system. Additionally, there is a functional alteration during the various stages of sleep. In nonrapid eye movement (NREM), a state of cardiovascular relaxation occurs during stages three and four. A large amount of rapid ocular movements is concentrated in rapid eye movement (REM) sleep. During this phase, fluctuations in arterial pressure (AP) and heart rate (HR) can be readily noted. Sleep disordered breathing (SDB) has been associated with cardiac rhythm disorders. Recently, cardiac rhythm disorder treatment with pacemaker (PM) highlighted a reduction in abnormal respiratory events during sleep. OBJECTIVE: Comparison of sleep parameters of patients using PM with a sleep rate (SR) algorithm based on its rate-modulated capability during physical activity (Integrity PM with SR function on and off). METHODS: Twenty-two patients (14 women, 8 men), implanted with an Integrity PM (St. Jude Medical Cardiac Rhythm Management Division, Sylmar, CA) with SR function for standard clinical indications, were evaluated utilizing a double-blind protocol. The indication for pacing included sinus node disease (SND), atrium ventricular blockage (AVB), and atrial fibrillation (AF). Following randomization, half of our patients had SR function switched to "on" mode while the other half were on "off" mode. During the first stage of the protocol, all patients underwent two consecutive nights of polysomnographic sleep recordings (PSG). During the first night patients slept in the sleep lab only for adaptation purpose. PSG full recording was carried out in the subsequent night. At a later stage, the programing of SR functions was shifted to "on" or "off" modes. One week later, a third assessment was undertaken. RESULTS: Twelve patients (54%) showed sleep efficiency improvement (total sleeping time/recording time) with PM SR on. This group had the least effective sleep efficiency with PM off, if compared with the others who highlighted no change in this sleep parameter (72 +/- 12 vs 81 +/- 7%, P = 0.01, respectively). This first group displayed a lower latency for REM sleep than the last one (89 +/- 55 vs 174 +/- 107 minutes, P = 0.01, respectively). In 11 (50%) patients, the number per sleep hour of microarousals was reduced when PM SR was switched on. When we compared such findings to the group whose parameters had not changed, we noted that the first set of patients were sleepier (ESE: 9 +/- 4 vs 5 +/- 5, P = 0.04, respectively), and showed more microarousals with PM SR off (20 +/- 14 vs 7 +/- 5 microarousal/hour, P = 0.007). CONCLUSION: In PM patients with sleep-related issues, the SR function activation improved sleep both from a qualitative and quantitative perspective.     

Influence of menstrual cycle and gender on alprazolam pharmacokinetics

The effects of menstrual cycle phases and gender on alprazolam pharmacokinetics were evaluated in normal volunteers. Alprazolam (1 mg) was administered to seven women during the late follicular and luteal phases of the menstrual cycle and to eight men on one occasion. No difference in alprazolam pharmacokinetic parameters was observed during the menstrual cycle phases. Mean alprazolam clearance (+/- SD) was 0.0037 +/- 0.0009 ml/hr during the follicular phase and 0.0036 +/- 0.001 ml/hr during the luteal phase (p greater than 0.05, difference not significant). With use of weight as a covariant, there was no difference in alprazolam pharmacokinetic parameters between women and men. Mean alprazolam clearance (+/- SD) was 0.0036 +/- 0.0009 ml/hr in women compared with 0.0041 +/- 0.0006 ml/hr in men (p greater than 0.05, difference not significant). Although alprazolam metabolism was similar on the 2 days tested, alterations may occur at other times during the menstrual cycle. Further investigation is needed to understand the effects of menstrual cycle phases and gender on drug metabolism.     

Significance of pharmacological blockade of angiotensin II type I receptors for correction of abnormal 24-hour blood pressure profile depending on its variability in patients with arterial hypertension stage II

AIM: To specify variable 24-h arterial hypertension (AH) stage II profile and to assess significance of pharmacological block of the end of the renin-angiotensin-aldosteron system for correction of the determined disorders. MATERIAL AND METHODS: The study was made of 46 men (mean age 42.8 +/- 3.28 years) with stage II AH and 25 normotensive controls (mean age 39.2 +/- 3.10 years). Depending on the magnitude of mean 24-h AP variability (APV), hypertensive patients were divided into two groups. Variability of systolic and/or diastolic AP (SAPV and DAPV, respectively) was considered high in at least 15.2 and/or 12.3 mm Hg variability, respectively, and normal at less values. RESULTS: AP 24-h profile in men with AH stage II and high APV compared to patients with normal APV is characterized by higher frequency of AP rise and less frequency of its night fall. In patients with high APV the drug eprosartan (teveten) is more effective in correction of hypertension and night fall of AP. CONCLUSION: Eprosartan has an adequate corrective activity in relation to absolute values of SAP and DAP in different hours. The highest hypotensive activity of the drug was seen in persons with initially high circadian AP variability within 24 hours.     

Growth hormone secretion during sleep

Plasma growth hormone (GH), insulin, cortisol, and glucose were measured during sleep on 38 nights in eight young adults. Blood was drawn from an indwelling catheter at 30-min intervals; EEG and electrooculogram were recorded throughout the night. In seven subjects, a plasma GH peak (13-72 mmug/ml) lasting 1.5-3.5 hr appeared with the onset of deep sleep. Smaller GH peaks (6-14 mmug/ml) occasionally appeared during subsequent deep sleep phases. Peak GH secretion was delayed if the onset of sleep was delayed. Subjects who were awakened for 2-3 hr and allowed to return to sleep exhibited another peak of GH secretion (14-46 mmug/ml). Peak GH secretion was not correlated with changes in plasma glucose, insulin, and cortisol. The effects of 6-CNS-active drugs on sleep-related GH secretion were investigated. Imipramine (50 mg) completely abolished GH peaks in two of four subjects, whereas chlorpromazine (30 mg), phenobarbital (97 mg), diphenylhydantoin (90 mg), chlordiazepoxide (20 mg), and isocarboxazid (30 mg) did not inhibit GH peaks. Altered hypothalamic activity associated with initiation of sleep results in a major peak of growth hormone secretion unrelated to hypoglycemia or changes in cortisol and insulin secretion.     

Fatigue and Sleep in Chronic Headache Sufferers: An Age- and Sex-Controlled Questionnaire Study

We studied fatigue and sleep in chronic headache sufferers in comparison to age- and sex-matched controls. We determined the prevalence and intensity of fatigue as well as several sleep features. The study was conducted in a headache center through the use of a questionnaire. One hundred thirteen headache sufferers (59 men and 54 women) and 110 controls (56 men and 54 women) were included in the analysis. Fatigue was found to be equally common in the headache sufferers (70.3%) and in the controls (60.0%). However, the headache sufferers rated the intensity of their fatigue significantly higher (4.1 versus 2.8 cm on a 10-cm visual analog scale). When the sexes were considered separately, the difference in intensity of the fatigue between the two groups was significant only for the women (5.1 versus 3.0 cm). With regard to sleep, the headache sufferers slept significantly shorter (6.7 hours) than the controls (7.0 hours). It also took them longer to fall asleep (31.4 versus 21.1 minutes) and longer to fall back asleep after waking up at night (28.5 versus 14.6 minutes). When the sexes were considered separately, the differences in sleep features between the two groups were significant only for the men.
On the basis of these results, we conclude that chronic headache sufferers feel more tired, especially the women, and do not sleep as well at night, especially the men. Further study is necessary to determine the significance of these findings in relation to chronic headache suffering.