Regular Sleep Schedule Research Articles

Manage narcolepsy with psychostimulants based on the individual’s most prominent symptoms, medical history and comorbidities

Narcolepsy is a chronic, neurological disorder of sleep–wake cycle dysregulation, for which most patients require lifelong pharmacological therapy. Recommended treatments include modafinil as first-line therapy for excessive daytime sleepiness (EDS), and sodium oxybate for first-line therapy for EDS with cataplexy and/or other associated symptoms (i.e. hypnagogic/hypnopompic hallucinations, sleep paralysis and disturbed nocturnal sleep). Behavioural strategies, such as taking planned naps and maintaining regular night-time sleep schedules, may provide complementary benefits to pharmacological therapy.

Treatment of behavioral sleep problems in children and adolescents - literature review.

To collect data on treatment of behavioural sleep disorders in children and adolescents. A literature review based on the PUBMED database. Based on the analysed materials three basic complementary procedures were identified - implementation of sleep hygiene, behavioural interventions and pharmacological treatment. The rules of sleep hygiene proven to be effective include: regular sleep schedule, adequately prepared place to sleep (a dark, quiet bedroom without multimedia), bedtime routine, avoiding caffeinated beverages. The following issues require further studies to confirm their effectiveness: falling asleep independently without parent's assistance, bedtime reading, physical activity, reducing daytime multimedia use, tryptophan rich breakfasts. Behavioural interventions and pharmacological treatment may in some cases be temporarily implemented to complement the sleep hygiene. The implementation of sleep hygiene is a primary, fully acceptable to the child and parents, way to improve the baby sleep. In case of ineffectiveness of the proposed rules, those can be complemented with behavioural methods that are highly effective but some parents do not accept them or make mistakes in their introduction. Pharmacotherapy can be used as a temporary support for families with severe behavioural problems as an aid in the implementation of sleep hygiene and behavioural methods.

Chronotype in patients with epilepsy: A controlled study in 60 subjects with late-onset focal epilepsy.

Studies based on self-administered questionnaires indicate that most patients with epilepsy are morning-oriented. We aimed to investigate chronotype in patients with epilepsy with late-onset focal epilepsy by combining subjective data with dim light melatonin onset (DLMO) as an objective marker of the circadian phase. Sixty adult patients (mean age 46.5±13.8; 27 males) with late-onset focal epilepsy under pharmacological treatment were prospectively studied. Subjective chronotype was determined using the Morningness-Eveningness Questionnaire (MEQ) and circadian phase through analysis of salivary melatonin secretion, considering 3pg/ml as the dim light melatonin onset (DLMO) threshold. The mean MEQ score was significantly higher in the patients with epilepsy than in the controls, and significantly, more patients had a MEQ score indicative of the morning type (50.0% vs 30.0%, p=0.02). However, no significant differences were found in mean time of DLMO (21:38±01:21 vs 21:26±01:03; p=ns), and DLMO time was in the range indicative of an intermediate chronotype in both patients and controls. Sleep onset and sleep offset phase angles were significantly shorter in the patients. Patients whose global MEQ score identified them as morning types were significantly older than those with an intermediate or evening chronotype, and they had less social jet lag. No difference in epilepsy features and treatments was found between morning-oriented and nonmorning-oriented patients. Our analyses showed that the patients with epilepsy tended to be morning-oriented and to perceive themselves as morning types, even though this was not reflected in their DLMO values which did not differ significantly from those of controls and mostly fell within the intermediate chronotype range. Several factors may considerably influence subjective chronotype. We speculate that, in patients with epilepsy, the disease itself, prompting certain lifestyle choices, including a regular sleep schedule and early bedtime, may induce morning orientation and a morning-type self-perception.

Irregular Bedtimes and Awakenings

Irregular bedtimes and awakenings may be a result of circadian rhythm sleep disorders. Further factors may also have a role in irregular sleep patterns, including lifestyle choice, psychiatric conditions, and substance use. For proper evaluation it is necessary to take a careful history with questioning that characterizes the timing of symptoms of insomnia and excessive sleepiness. Further diagnostic assessment may be indicated to rule out other potential causes of complaints. Treatments include regular sleep schedule, phototherapy, cognitive behavioral therapy for insomnia, chronotherapy, and melatonin. Given the significant psychosocial consequences of these disorders, one must recognize the conditions and intervene promptly.

Behavioral treatment of insomnia: also effective for nocturia.

To evaluate changes in self-reported nocturia in community-dwelling adults aged 60 and older who received behavioral treatment for chronic insomnia. Secondary analysis of a randomized controlled trial of a behavioral intervention for sleep. Academic medical center. Of the 79 enrollees, this analysis focused on 30 who, in addition to insomnia, also reported at least one nightly episode of waking up to void. The brief behavioral treatment of insomnia (BBTI) group (n = 14) received instructions on reducing time in bed and setting a regular sleep schedule. The information control (IC) group (n = 16) received printed materials. A nurse clinician delivered both interventions. Self-reported nocturnal awakenings to void assessed daily for 14 days at baseline and 4 weeks after the intervention. Participants who reported at least one episode of nocturia per night at baseline were included in this analysis. In individuals with nocturia at baseline, the total number of nocturnal voids over the 14-day assessment period decreased by 6.5 ± 4.8 in the BBTI group and increased by 1.3 ± 7.3 in the IC group (P = .04, effect size 0.82). After adjusting for baseline nocturia episodes, the difference remained significant (P = .05). In older adults with concurrent insomnia and nocturia, behavioral treatment directed solely at insomnia may also improve self-reported nocturia. Behavioral treatment of insomnia should be further investigated for its effect on nocturia in individuals with concurrent insomnia and nocturia.

Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study.

BackgroundThe mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea.ObjectiveTo analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample.MethodsCross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart®) system.ResultsA total of 767 participants (461 men) with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat) was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001). After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia.ConclusionNocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.

The circadian rhythm of blood pressure is masked by postural changes

It is well known that blood pressure (BP) varies throughout the day with lower levels observed during nocturnal sleep. This diurnal rhythm is partly explained by the BP-lowering effect of sleep and by an endogenous circadian rhythm of BP with a nocturnal through. As BP is acutely responsive to postural changes, the present study aimed at clarifying how posture affects the circadian variation of BP. Eleven healthy subjects (10 men, 1 woman; mean age ¡À SD: 22.6 ¡À 3.4 years old) were studied individually in time isolation for 6 consecutive days. After 2 baseline days on their regular sleep schedule, subjects underwent a 72-h ultradian sleep–wake cycle (USW) procedure, which consists of 60-min wake periods in dim light ( < 10 lux) alternating with 60-min naps in darkness ( < 0.3 lux). Subjects remained in a semi- recumbent posture throughout the first 48 h of the USW procedure. During the last 24 h of the USW procedure, they slept in a supine position during naps and changed into a sitting and standing position at 5 and 10 min after lights on, respectively. They returned to a sitting then supine position at 22 and 56 min after light on, respectively. BP was measured 1, 6, 11, 16 and 21 min after lights on. Circadian phase was assessed from core body temperature (CBT) (4x/min) which minimum was determined by a dual-harmonic regression and assigned a circadian phase of 0 degree. BP measures were averaged per subject by 60-degree bins and analyzed using non-linear mixed models. As expected, postural changes affected BP levels. No BP change was observed throughout wake periods when subjects remained in a semi-recumbent posture ( P ¡Ý0.38). In comparison, during the last 24 h of the USW procedure, diastolic (DBP) and mean arterial BP (MAP) increased by 11.97 ¡À 2.11 and 10.11 ¡À 2.34 mmHg, respectively, when participants changed from the supine to the standing position (measured 1 and 21 min after lights on, respectively; P < 0.001). Moreover, we observed a significant circadian rhythm of systolic BP (SBP), DBP, and MAP ( P ¡Ü0.001) during wake periods without postural change, with an acrophase occurring 7.4 ¡À 0.2 h, 8.6 ¡À 0.3 h and 7.0 ¡À 0.3 h after subjects¡ ¯ regular wake time, respectively. In comparison, during the postural change segment of the USW procedure, none of these rhythms were of sufficient amplitude to be significant, even though average values were comparable. Our observations indicate that postural changes significantly mask the endogenous circadian rhythm of BP. These results have practical implications for the measurement and interpretation of BP data collected in field conditions. Even when sleep is controlled for, the determination of circadian phase and amplitude of BP in ambulatory conditions is of limited value due to the confounding effects of changes in activity levels and posture. This research was supported by an operating grant from the Canadian Institutes of Health Research (CIHR). P. Boudreau was supported by a fellowship from the Institut de recherche Robert-Sauv ¨ ∣ en sant ¨ ∣ et en s ¨ ∣ curit ¨ ∣ du travail (IRSST).

Alerting effects of short-wavelength (blue) and long-wavelength (red) lights in the afternoon

Light has an acute effect on neuroendocrine responses, performance, and alertness. Most studies to date have linked the alerting effects of light to its ability to suppress melatonin, which is maximally sensitive to short-wavelength light. Recent studies, however, have shown alerting effects of white or narrowband short-wavelength lights during daytime, when melatonin levels are low. While the use of light at night to promote alertness is well understood, it is important to develop an understanding of how light impacts alertness during the daytime, especially during the post-lunch hours. The aim of the current study was to investigate how 48-minute exposures to short-wavelength (blue) light (40lux, 18.9microWatts/cm2 λmax=470nanometers [nm]) or long-wavelength (red) light (40lux, 18.9microWatts/cm2 λmax=630nm) close to the post-lunch dip hours affect electroencephalogram measures in participants with regular sleep schedules. Power in the alpha, alpha theta, and theta ranges was significantly lower (p<0.05) after participants were exposed to red light than after they remained in darkness. Exposure to blue light reduced alpha and alpha theta power compared to darkness, but these differences did not reach statistical significance (p>0.05). The present results extend those performed during the nighttime, and demonstrate that light can be used to increase alertness in the afternoon, close to the post-lunch dip hours. These results also suggest that acute melatonin suppression is not needed to elicit an alerting effect in humans.

Childhood obesity and sleep: relatives, partners, or both?--a critical perspective on the evidence.

In modern life, children are unlikely to obtain sufficient or regular sleep and waking schedules. Inadequate sleep affects the regulation of homeostatic and hormonal systems underlying somatic growth, maturation, and bioenergetics. Therefore, assessments of the obesogenic lifestyle, including as dietary and physical activity, need to be coupled with accurate evaluation of sleep quality and quantity, and coexistence of sleep apnea. Inclusion of sleep as an integral component of research studies on childhood obesity should be done as part of the study planning process. Although parents and health professionals have quantified normal patterns of activities in children, sleep has been almost completely overlooked. As sleep duration in children appears to have declined, reciprocal obesity rates have increased. Also, increases in pediatric obesity rates have markedly increased the risk of obstructive sleep apnea syndrome (OSAS) in children. Obesity and OSAS share common pathways underlying end-organ morbidity, potentially leading to reciprocal amplificatory effects. The relative paucity of data on the topics covered in the perspective below should serve as a major incentive toward future research on these critically important concepts.

Nutritional Modulators of Sleep Disorders

Background: Clinical evidence indicates that insufficient sleep and poor sleep quality appear to be common consequences of shift work. These rhythms appear to have independent influence on the function of the endocrine system, circadian brain function and gastrointestinal tract. Insufficient sleep and its poor quality due to shift work interfere with beta cells, leptin and ghrelin functioning, resulting in factors for the development and exacerbation of insulin resistance. Human studies found that insufficient sleep alters the levels of leptin and ghrelin, two hormones involved in the regulation of appetite and body fat. Leptin, released by fat cells, signals the brain to feel satiety. Ghrelin, produced in the stomach, signals hunger. Investigations reported that temporarily sleep-deprived individuals experienced hormonal changes along with greater cravings for sweet and fatty foods. A further reason for their cravings is related to the stress hormone cortisol, which can rise with sleep deprivation and contribute to hunger. In addition to altered hormone levels, people who stay awake longer have more opportunity to eat, and late-night eating often includes high-caloric foods. Weight gain is only one of the many side effects of insufficient sleep, but it can lead to long-term health problems, including diabetes. Although more sleep will not automatically result in weight loss, sufficient sleep and a regular sleep schedule are critical in controlling appetite and promoting a healthy eating pattern. Research on sleep and appetite reveals a consistent link between a lower amount of sleep and a higher body mass index (BMI), a ratio of weight-to-height that indicates overweight. Studies showed those who slept less than eight hours a night were more likely to be overweight. Methods: Internet search and discussion with colleagues. Results: Recent research indicates that disruption of sleep can influence food intake and food and nutrients can influence sleep. There is evidence that high protein and carbohydrates meals can influence moods, attention and concentration among normal adult subjects with respect to age, gender and meal time. Women reported greater sleepiness after two hours of carbohydrate meal as opposed to a protein meal. On the other hand men reported greater calmness after a carbohydrate as opposed to a protein meal. Age of subjects may also influence the response to meals. After a carbohydrate or protein rich breakfast, persons older than 40 years felt more tense and less calm with a protein-rich than carbohydrate- rich meal. In general older subjects preferred carbohydrate than protein meals. Carbohydrate meals are also reported to impair objective performance; carbohydrate rich foods either in breakfast or lunch have exhibited negative influence on neural response such as impaired objective performance and poor sustained attention. A meal consumed close to bedtime is associated with sleep disturbances. Further, solid foods as well as large meals may cause more sleepiness than liquid foods. Studies have also shown that the larger the meal, the sleepier the person thereafter. In the evening the sleep- facilitating effects of carbohydrates may be beneficial. However, manipulation in the energy content of meals for a single day may cause increase in markedly different levels of insulin without changes in plasma glucose. Conclusions: The findings indicate that food intake can influence sleep and disruption of sleep can cause increased consumption of fast ready-prepared foods which have adverse effects resulting in obesity, diabetes and CVDs.

Hábitos y problemas con el sueño de los 6 a los 14 años en la Comunidad Valenciana. Opinión de los propios niños

Introduction The sleep habits and the prevalence of sleep problems have been poorly evaluated globally in Spain. The objective is to find out the opinions of the paediatric population in of an autonomous community as a whole (Comunidad Valenciana) on sleep and its difficulties, and to analyse their distribution by age, sex and geographical origin. Material and methods An observational, descriptive epidemiological study of prevalence. The Children Sleep Habits Questionnaire was used. The sample was obtained proportionally to the population of the three provinces of the Community of Valencia and depending on the place of residence: urban and rural, coastal zone/Interior. We evaluated the responses of 1507 questionnaires. Results Between 91.2% and 76.1% believed that they have problems sleeping with a relationship of dependency with age. Fifteen percent of the sample lack a regular sleep schedule during school days and 19.7% of the 9–11 years themselves decided their own sleep schedules during school days. A majority (53.9% of the 12–15 years had nightmares more than once per week and 37.4% (6–8 years), 25.3% (9–11 years) and 31.8% (12–15 years) never woke up tired or did so only once per week. Conclusions Poor sleep habits are prevalent. It is necessary to increase the educational measures and explain the importance of sleep. Teenagers are a particularly sensitive to poor sleep habits group. Environmental factors (place of residence) should be taken into account when assessing sleep.

A Sleepy Patient with REM Rebound

A 25-year-old male presented to the sleep clinic with a chief complaint of excessive daytime somnolence and witnessed nocturnal “choking episodes” dating back a few years. His Epworth Sleepiness Scale score was 13. His usual bed time and rise time were 23:00 and 07:00, respectively. There was no history of snoring, and the patient denied a history of cataplexy, hypnopompic/hypnagogic hallucinations, or sleep paralysis. Six weeks prior to his sleep study, his primary care physician had prescribed paroxetine 20 mg daily, and 2 weeks prior to the study, trazodone 50 mg at bedtime had been added to his medication regimen. These medications were prescribed to treat depression with comorbid anxiety that had been present for many years but were not currently treated. In spite of a regular sleep schedule of 8 h per night, he often fell asleep on the job. The patient noted that his excessive daytime sleepiness predated the use of the antidepressants. His family history was positive for a father with obstructive sleep apnea. His physical examination revealed normal vital signs with a body mass index of 23.5. Head, ears, eyes, nose and throat examination were unremarkable, as was the cardiopulmonary examination. An overnight diagnostic polysomnogram (PSG) was obtained with the hypnogram shown in Figure 1 and a summary of pertinent results in Table 1. Figure 1 Hypnogram showing the summary of sleep stages for the sleep period. Note the large amount of REM sleep (as designated by R in the y axis) with the arrows pointing to these areas of interest. Table 1 Diagnostic Polysomnogram Summary of Sleep Time Statistics, Sleep Stage Statistics and Respiratory Event Statistics A multiple sleep latency test (MSLT) was ultimately obtained following the PSG to evaluate objectively his severity of somnolence (Table 2). Table 2 Results of the Multiple Sleep Latency Test Question: What additional information would be important to request from the patient to help explain the findings seen on the PSG and MSLT? Answer: A list of any medications or recreational drugs recently started or stopped. One may consider drug screening to ensure that the findings are not pharmacologically induced. Sleep logs for 1 week prior to the MSLT to assess prior sleep-wake schedules can sometimes be helpful to look for insufficient sleep.

Phase delaying the human circadian clock with a single light pulse and moderate delay of the sleep/dark episode: no influence of iris color

BackgroundLight exposure in the late evening and nighttime and a delay of the sleep/dark episode can phase delay the circadian clock. This study assessed the size of the phase delay produced by a single light pulse combined with a moderate delay of the sleep/dark episode for one day. Because iris color or race has been reported to influence light-induced melatonin suppression, and we have recently reported racial differences in free-running circadian period and circadian phase shifting in response to light pulses, we also tested for differences in the magnitude of the phase delay in subjects with blue and brown irises.MethodsSubjects (blue-eyed n = 7; brown eyed n = 6) maintained a regular sleep schedule for 1 week before coming to the laboratory for a baseline phase assessment, during which saliva was collected every 30 minutes to determine the time of the dim light melatonin onset (DLMO). Immediately following the baseline phase assessment, which ended 2 hours after baseline bedtime, subjects received a 2-hour bright light pulse (~4,000 lux). An 8-hour sleep episode followed the light pulse (i.e. was delayed 4 hours from baseline). A final phase assessment was conducted the subsequent night to determine the phase shift of the DLMO from the baseline to final phase assessment.Phase delays of the DLMO were compared in subjects with blue and brown irises. Iris color was also quantified from photographs using the three dimensions of red-green-blue color axes, as well as a lightness scale. These variables were correlated with phase shift of the DLMO, with the hypothesis that subjects with lighter irises would have larger phase delays.ResultsThe average phase delay of the DLMO was -1.3 ± 0.6 h, with a maximum delay of ~2 hours, and was similar for subjects with blue and brown irises. There were no significant correlations between any of the iris color variables and the magnitude of the phase delay.ConclusionA single 2-hour bright light pulse combined with a moderate delay of the sleep/dark episode delayed the circadian clock an average of ~1.5 hours. There was no evidence that iris color influenced the magnitude of the phase shift. Future studies are needed to replicate our findings that iris color does not impact the magnitude of light-induced circadian phase shifts, and that the previously reported differences may be due to race.

P03-246 Acute effect of blue light exposition on well-being and melatonin secretion in humans

Aim:The aim of this study was to investigate the efficacy of blue light emitting diode units in suppression of melatonin secretion and to evaluate whether a single exposure can improve well being in healthy males and females (20/30) and in 15 women with premenstrual syndrome.Methods:All study participants were of morning-type with a regular sleep schedule. On control day 1, the subjects were kept under dim illumination (&lt; 10 lx) from 19:00 to 22:30. On day 2, after 1.5h in dim light, the subjects were exposed for 60 min to blue light (12.15 μM/cm², TurboLite, Germany) following by 30 min dim light. Blood samples were collected every 30 min for melatonin assay. Zerssen's complaints scale was used to assess mental und physical well-being at 19:00 (pre-test) and at 22:30 (post-test) after dim illumination or blue light exposure. In addition a visual analogue scale (VAS) for sleepiness was applied.Results:Overall, blue light improved significantly mental and physical complaints from pre-test to post-test (reduction in sum score of the Zerssen's complaints scale by in average 30%) and reduced sleepiness, as measured by the VAS. There were gender-related differences, as well as differences related to the menstrual phase in females. Blue light reduced but not suppressed the gradual increase of melatonin in plasma with time mostly pronounced in the follicular phase.Conclusion:A single exposition with blue light of low radiant flux density, as applied in our study, seems to be helpful in reducing mental and physical distress.

Impact of sleep patterns on mood and academic performance of medical students

Sleep a vital biological process is essential for physical & psychological restoration. Owing to their hectic schedules, medical students, in particular, are known to have erratic sleep patterns and suffer from sleep disturbances, fatigue and mood changes. This study was designed to analyze the sleep patterns and to correlate sleep deprivation with incidence of anxiety, depression, daytime sleepiness and performance among 100 students of 1st year MBBS by means of a validated questionnaire. 44% students reported sleeping >8 Hrs and only 51% were regular in their sleep schedule. Females (32%) were found to follow a more regular sleep schedule compared to males (68%) and reported better performance and lesser level of anxiety and depression in those sleeping for more than 8 hrs. Day scholars had a better and a regular schedule compared to hostellers and they also had significantly (p =0.034) better performance. This study found that an old saying “early to bed and early to rise makes man healthy, wealthy and wise” holds true. Those following regular schedule, sleeping early and rising early in the morning have better academic performance and lower levels of anxiety and depression. This study highlights the prevalence of disturbed sleep patterns as a significant cause of poor performance and mood disturbances in medical students.

The Association Between Television Viewing and Irregular Sleep Schedules Among Children Less Than 3 Years of Age

Regular sleep schedules are an important part of healthy sleep habits. Although television viewing is associated with altered sleep patterns and sleep disorders among children and adolescents, the effect of television viewing on the sleep patterns of infants and toddlers is not known. To test the hypothesis that television viewing by infants and toddlers is associated with having irregular naptime and bedtime schedules. We used data from the National Survey of Early Childhood Health, a nationally representative, cross-sectional study of the health and health care of children 4 to 35 months of age. Our main outcome measures were whether children had irregular naptime and bedtime schedules. Our main predictor was hours of television watched on a daily basis. We performed multivariate logistic regression analyses, adjusting for a variety of factors including demographic information, measures of maternal mental health, and measures of family interactions, to test the independent association of television viewing and irregular naptime and bedtime schedules. Data were available for 2068 children. Thirty-four percent of all children had irregular naptime schedules, and 27% had irregular bedtime schedules. Mean hours of television viewing per day were as follows: 0.9 hours/day (95% confidence interval [CI]: 0.8-1.0 hours/day) for children <12 months of age, 1.6 hours/day (95% CI: 1.4-1.8 hours/day) for children 12 to 23 months of age, and 2.3 hours/day (95% CI: 2.1-2.5 hours/day) for children 24 to 35 months of age. In our logistic regression model, the number of hours of television watched per day was associated with both an irregular naptime schedule (odds ratio: 1.09; 95% CI: 1.01-1.18) and an irregular bedtime schedule (odds ratio: 1.13; 95% CI: 1.04-1.24). Television viewing among infants and toddlers is associated with irregular sleep schedules. More research is warranted to determine whether this association is causal.

Individual Differences in the Consideration of Future Consequences Scale Correlate with Sleep Habits, Sleep Quality, and GPA in University Students

The present study examined relationships between individual differences in the consideration of future consequences, sleep habits and sleep quality, and academic achievement in a sample of 231 undergraduates, 156 women and 75 men, whose ages ranged from 18 to 41 years (M = 19.0 yr., SD=2.82). Individuals were recruited from two introductory courses and two upper-division courses, one each in the fields of biology and psychology. An 8-page questionnaire was administered to assess variables relating to personality, sleep habits and quality, and grade point average (GPA). Each volunteer was given extra credit in their respective courses for participation. Higher scores on the Consideration of Future Consequences scale were associated with self-reported measures of more regular sleep schedules, greater satisfaction with sleep, a reduced likelihood of oversleeping, and higher grade point averages. Moreover, oversleeping was significantly correlated with both scale scores and GPA.

Stability of Melatonin and Temperature as Circadian Phase Markers and Their Relation to Sleep Times in Humans

Circadian rhythms of core body temperature and melatonin are commonly used as phase markers of the circadian clock. Melatonin is a more stable marker of circadian phase when measured under constant routine conditions. However, little is known about the variability of these phase markers under less controlled conditions. Moreover, there is little consensus about the preferred method of analysis. The objective of this study was to assess various methods of calculating melatonin and temperature phase in subjects with regular sleep schedules living in their natural environment. Baseline data were analyzed from 42 healthy young subjects who were studied on at least two occasions. Each hospital admission was separated by at least 3 weeks. Subjects were instructed to maintain a regular sleep schedule, which was monitored for 1 week before admission by sleep logs and actigraphy. Subjects spent one habituation night under controlled conditions prior to collecting baseline temperature and melatonin measurements. The phase of the melatonin rhythm was assessed by 9 different methods. The temperature nadir (Tmin) was estimated using both Cleveland and Cosine curve fitting procedures, with and without demasking. Variability between admissions was assessed by correlation analysis and by the mean absolute difference in timing of the phase estimates. The relationship to sleep times was assessed by correlation of sleep onset or sleep offset with the various phase markers. Melatonin phase markers were more stable and more highly correlated with the timing of sleep than estimates of Tmin. Of the methods for estimating Tmin, simple cosine analysis was the least variable. In addition, sleep offset was more strongly correlated with the various phase markers than sleep onset. The relative measures of melatonin offset had the highest correlation coefficients, the lowest study-to-study variability, and were more strongly associated with sleep timing than melatonin onsets. Concordance of the methods of analysis suggests a tendency for the declining phase of the melatonin profile to be more stable and reliable than either markers of melatonin onset or measures of the termination of melatonin synthesis.

Chronic insomnia and immune functioning.

The goal of this study was to investigate whether clinical insomnia is associated with immune alterations by comparing immune functioning between patients with chronic insomnia and good sleepers. The good sleepers group was composed of 19 adults with a regular sleep schedule and no complaint of sleep disturbances. The insomnia group was composed of 17 adults meeting criteria for a chronic primary insomnia disorder. Peripheral blood samples were taken at the interview (time 1) and before the second night of polysomnographic assessment (time 2) for immune measures, including enumeration of blood cell counts (ie, white blood cells, monocytes, lymphocytes, and CD3+, CD4+, CD8+, and CD16+/CD56+ cells), natural killer cell activity, and cytokine production (ie, interleukin-1beta, interleukin-2, and interferon gamma). Significant between-group differences were observed for CD3+, CD4+, and CD8+ cells, with higher levels found in good sleepers. In addition, a significant group-by-time interaction was found on monocyte counts. Although this was the only significant interaction effect observed, between-group differences were greater at time 2. This study suggests that chronic insomnia is associated with some immune alterations. More research is needed to determine the clinical significance of these findings.

The role of nonpharmaceutic conservative interventions in the treatment and secondary prevention of epilepsy.

Nonpharmacologic conservative treatments receive too little attention. Depending on the clinical condition of the patients, they may be used alone or in conjunction with other therapies. Their target is the single seizure rather than the epileptic condition as such. They belong mainly to one of three domains. NONSPECIFIC PREVENTION OF SEIZURES: The first step is the identification of factors facilitating the occurrence of seizures. In the second step, strategies to control these factors are developed. Most common are disturbances of the sleep-wake cycle, especially reduction of sleep. Patients should follow a regular sleep schedule with deviations of not >2 h. Sometimes a sleep calendar is helpful. Night shifts are not compatible with seizure prevention in these cases. Sleep disturbances as a facilitating factor of seizures are particularly common in juvenile idiopathic generalized epilepsies, in which their avoidance is in many cases an indispensable part of the therapeutic regimen, along with appropriate drug treatment. They are the most common precipitating factor in adolescents and adults with a first epileptic [mostly generalized tonic-clonic (GTC)] seizure. In these instances, their avoidance is central to the secondary prevention of epilepsy developing from the single seizure, whereas the prescription of antiepileptic drugs (AEDs) is rarely effective. Other nonspecific facilitators of seizures include uncontrolled use of alcohol and extraordinary stress. Patients must learn how to cope with stressful events. SPECIFIC PREVENTION OF SEIZURES: In reflex epilepsies, specific precipitants of seizures are the targets of interventions. Thus, most patients with primary reading epilepsy begin to have, with prolonged reading, perioral reflex myoclonias, which enable them to stop reading and thus to avoid a GTC seizure. In photosensitive patients, seizures are often precipitated by television. These can be avoided by viewing from a distance and using a remote control, small screens in a well-lit room, and preferably with a 100-Hz line shift. Environmental flicker stimulation often comes unexpectedly, and it is advisable that the patients always wear sunglasses in brightly lighted surroundings. Polarized glasses seem to be more protective than plain sunglasses. If the patient has only photically induced seizures, treatment by specific prevention alone may be sufficient, but if spontaneous seizures also occur, drugs must be given in addition. ARREST OF SEIZURES: Focal seizures that develop sufficiently slowly to leave the patient time to react may be interrupted by "countermeasures." These, again, may be nonspecific (acting by relaxation, concentration, or a combination of both) or specific. The latter are individually tailored, based either on spontaneous experiences of the patient or on the anatomy of ictogenesis. Seizure propagation is blocked when a major part of the neurons involved is activated and not recruitable for spread of the epileptic discharge. Seizure arrest rarely is used alone but usually in combination with partially successful pharmacotherapy.