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A Kales

Publications and source records attributed to A Kales.

At least 19 recordsLinked to original sources

Insomnia in central Pennsylvania.

OBJECTIVE: Establish the association between insomnia and various physical and mental health symptoms as well as objective measures of sleep disturbance while controlling for age, gender and BMI in a large random sample of the general public. METHODS: A subsample (N=1741) was selected for a single-night sleep laboratory evaluation from a larger random sample (N=16,583) of the general public (20-100 years old). RESULTS: The prevalence of insomnia was 7.5% and difficulty sleeping an additional 22.4%. The complaints were more frequent in women and in non-Caucasian minorities. A multivariate logistic regression analysis indicated that depression was the single strongest factor followed by female gender associated with either insomnia or difficulty sleeping. Minority status and a history of colitis, hypertension and anemia were also associated, but to a lesser degree. The final model did not include age, BMI as well as any of the sleep laboratory findings. CONCLUSION: These findings support the conclusion that mental health variables have the primary independent association with a complaint of insomnia. Other factors including minorities and hypertension are also independently associated, though to a lesser degree. Other primary sleep disorders, e.g., sleep apnea, do not seem to play a major role in insomnia. These findings underscore the fact that insomnia is a symptom associated with a wide variety of mental and physical health problems requiring a proper psychiatric and medical management.

Adult↗

Chronic insomnia is associated with a shift of interleukin-6 and tumor necrosis factor secretion from nighttime to daytime.

Chronic insomnia, by far the most commonly encountered sleep disorder in medical practice, is characterized by difficulty falling or staying asleep at night and increased fatigue during the day. Interleukin-6 (IL-6) and tumor necrosis factor (TNF) are fatigue-inducing cytokines, and the daytime secretion of IL-6 is negatively influenced by the quantity and quality of the previous night's sleep. We hypothesize that the poor quality of insomniacs' sleep is associated with a hypersecretion of these 2 cytokines during the daytime, which, in turn, correlates with the fatigue experienced by these patients. Eleven young insomniacs (6 men and 5 women) and 11 (8 men and 3 women) age- and body mass index (BMI)-matched healthy controls participated in the study. Subjects were recorded in the sleep laboratory for 4 consecutive nights and serial 24-hour plasma measures of IL-6 and TNF were obtained during the 4th day. Insomniacs compared to controls slept poorly (sleep latency and wake were increased, whereas percentage sleep time was decreased during baseline nights, all P <.05). The mean 24-hour IL-6 and TNF secretions were not different between insomniacs and controls. However, the difference in the change (increase) of IL-6 plasma levels from midafternoon (2 PM) to evening (9 PM) between insomniacs and controls was significant (P <.01). Furthermore, cosinor analysis showed a significant shift of the major peak of IL-6 secretion from nighttime (4 AM) to evening (7 PM) in insomniacs compared to controls (P <.05). Also, while TNF secretion in controls showed a distinct circadian rhythm with a peak close and prior to the offset of sleep (P <.05), such a rhythm was not present in insomniacs. Finally, daytime secretion of TNF in insomniacs was characterized by a regular rhythm of 4 hours (P <.05); such a distinct periodicity was not present in controls. We conclude that chronic insomnia is associated with a shift of IL-6 and TNF secretion from nighttime to daytime, which may explain the daytime fatigue and performance decrements associated with this disorder. The daytime shift of IL-6 and TNF secretion, combined with a 24-hour hypersecretion of cortisol, an arousal hormone, may explain the insomniacs' daytime fatigue and difficulty falling asleep.

Adult↗

Prevalence of sleep-disordered breathing in women: effects of gender.

The prevalence of sleep-disordered breathing has not been well studied in women, especially in terms of the effects of age, body mass index (BMI), and menopause. We evaluated this question using a two-phase random sample from the general population. In Phase I, 12,219 women and 4,364 men ranging in age from 20 to 100 yr were interviewed; and in Phase II, 1,000 women and 741 men of the Phase I subjects were selected for one night of sleep laboratory evaluation. The results of our study indicated that, for clinically defined sleep apnea (apnea/hypopnea index > or = 10 and daytime symptoms), men had a prevalence of 3.9% and women 1.2%, resulting in an overall ratio of sleep apnea for men to women of 3.3:1 (p = 0.0006). The prevalence of sleep apnea was quite low in premenopausal women (0.6%) as well as postmenopausal women with hormone replacement therapy (HRT) (0.5%). Further, in these women the presence of sleep apnea appeared to be associated exclusively with obesity (BMI > or = 32.3 kg/m2). Postmenopausal women without HRT had a prevalence of sleep apnea that was significantly higher than the prevalence in premenopausal women with HRT (2.7 versus 0.6%, p = 0.02) and was more similar to the prevalence in men (3.9%), although it remained significantly less when controlling for age and BMI (p = 0.001). These data combined indicate that menopause is a significant risk factor for sleep apnea in women and that hormone replacement appears to be associated with reduced risk.

Adult↗

Polycystic ovary syndrome is associated with obstructive sleep apnea and daytime sleepiness: role of insulin resistance.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder of premenopausal women, characterized by chronic hyperandrogenism, oligoanovulation, and insulin resistance. Obstructive sleep apnea (OSA) and excessive daytime sleepiness (EDS) are strongly associated with insulin resistance and hypercytokinemia, independently of obesity. We hypothesized that women with PCOS are at risk for OSA and EDS. Fifty-three women with PCOS (age range, 16-45 yr) and 452 control premenopausal women (age range, 20-42), from a general randomized sample for the assessment of prevalence of OSA, were evaluated in the sleep laboratory for 1 night. In addition, women with PCOS were tested for plasma free and weakly bound testosterone, total testosterone, and fasting blood glucose and insulin concentrations. In this study, PCOS patients were 30 times more likely to suffer from sleep disordered breathing (SDB) than the controls [odds ratio = 30.6, 95% confidence interval (7.2-139.4)]. Nine of the PCOS patients (17.0%) were recommended treatment for SDB, in contrast with only 3 (0.6%) of the control group (P < 0.001). In addition, PCOS patients reported more frequent daytime sleepiness than the controls (80.4% vs. 27.0%, respectively; P < 0.001). PCOS patients who were recommended treatment for SDB, compared with those who were not, had significantly higher fasting plasma insulin levels (306.48 +/- 52.39 vs. 176.71 +/- 18.13 pmol/L, P < 0.01) and a lower glucose-to-insulin ratio (0.02 +/- 0.00 vs. 0.04 +/- 0.00, P < 0.05). Plasma free and total testosterone and fasting blood glucose concentrations were not different between the two groups of PCOS women. Our data indicate that SDB and EDS are markedly and significantly more frequent in PCOS women than in premenopausal controls. Also, insulin resistance is a stronger risk factor than is body mass index or testosterone for SDB in PCOS women. These data support our proposal that, independently of gender, sleep apnea might be a manifestation of an endocrine/metabolic abnormality in which insulin resistance plays a principal role.

Adolescent↗

Middle-aged men show higher sensitivity of sleep to the arousing effects of corticotropin-releasing hormone than young men: clinical implications.

The prevalence of insomnia associated with emotional stress increases markedly in middle-age. Both the top and end hormones of the hypothalamic-pituitary-adrenal axis, i.e. CRH and glucocorticoids, stimulate arousal/wakefulness and inhibit slow wave (deep) sleep in experimental animals and man. The objective of this study was to test the hypothesis that middle-age is characterized by increased sensitivity to the sleep-disturbing effects of the hypothalamic-pituitary-adrenal axis. We studied 12 healthy middle-aged (45.1 +/- 4.9) and 12 healthy young (22.7 +/- 2.8) men by monitoring their sleep by polysomnography for 4 consecutive nights, including in tandem 1 adaptation and 2 baseline nights and a night during which we administered equipotent doses of ovine CRH (1 microg/kg, iv bolus) 10 min after sleep onset. Analyses included comparisons within and between groups using multiple ANOVA and regression analysis. Although both middle-aged and young men responded to CRH with similar elevations of ACTH and cortisol, the former had significantly more wakefulness and suppression of slow wave sleep compared with baseline sleep; in contrast, the latter showed no change. Also, comparison of the change in sleep patterns from baseline to the CRH night in the young men to the respective change observed in middle-aged men showed that middle-age was associated with significantly higher wakefulness and significantly greater decrease in slow wave sleep than in young age. We conclude that middle-aged men show increased vulnerability of sleep to stress hormones, possibly resulting in impairments in the quality of sleep during periods of stress. We suggest that changes in sleep physiology associated with middle-age play a significant role in the marked increase of prevalence of insomnia in middle-age.

Adrenocorticotropic Hormone↗

Chronic insomnia is associated with nyctohemeral activation of the hypothalamic-pituitary-adrenal axis: clinical implications.

Although insomnia is, by far, the most commonly encountered sleep disorder in medical practice, our knowledge in regard to its neurobiology and medical significance is limited. Activation of the hypothalamic-pituitary-adrenal axis leads to arousal and sleeplessness in animals and humans; however, there is a paucity of data regarding the activity of the hypothalamic-pituitary-adrenal axis in insomniacs. We hypothesized that chronic insomnia is associated with increased plasma levels of ACTH and cortisol. Eleven young insomniacs (6 men and 5 women) and 13 healthy controls (9 men and 4 women) without sleep disturbances, matched for age and body mass index, were monitored in the sleep laboratory for 4 consecutive nights, whereas serial 24-h plasma measures of ACTH and cortisol were obtained during the fourth day. Insomniacs, compared with controls, slept poorly (significantly higher sleep latency and wake during baseline nights). The 24-h ACTH and cortisol secretions were significantly higher in insomniacs, compared with normal controls (4.2 +/- 0.3 vs. 3.3 +/- 0.3 pM, P = 0.04; and 218.0 +/- 11.0 vs. 190.4 +/- 8.3 nM, P = 0.07). Within the 24-h period, the greatest elevations were observed in the evening and first half of the night. Also, insomniacs with a high degree of objective sleep disturbance (% sleep time < 70), compared with those with a low degree of sleep disturbance, secreted a higher amount of cortisol. Pulsatile analysis revealed a significantly higher number of peaks per 24 h in insomniacs than in controls (P < 0.05), whereas cosinor analysis showed no differences in the temporal pattern of ACTH or cortisol secretion between insomniacs and controls. We conclude that insomnia is associated with an overall increase of ACTH and cortisol secretion, which, however, retains a normal circadian pattern. These findings are consistent with a disorder of central nervous system hyperarousal rather than one of sleep loss, which is usually associated with no change or decrease in cortisol secretion or a circadian disturbance. Chronic activation of the hypothalamic-pituitary-adrenal axis in insomnia suggests that insomniacs are at risk not only for mental disorders, i.e. chronic anxiety and depression, but also for significant medical morbidity associated with such activation. The therapeutic goal in insomnia should be to decrease the overall level of physiologic and emotional arousal, and not just to improve the nighttime sleep.

Adrenocorticotropic Hormone↗

Sleep apnea and daytime sleepiness and fatigue: relation to visceral obesity, insulin resistance, and hypercytokinemia.

Sleep apnea and associated daytime sleepiness and fatigue are common manifestations of mainly obese middle-aged men. The onset of sleep apnea peaks in middle age, and its morbid and mortal sequelae include complications from accidents and cardiovascular events. The pathophysiology of sleep apnea remains obscure. The purpose of this study was to test three separate, albeit closely related, hypotheses. 1) Does sleep apnea contribute to the previously reported changes of plasma cytokine (tumor necrosis factor-alpha and interleukin-6) and leptin levels independently of obesity? 2) Among obese patients, is it generalized or visceral obesity that predisposes to sleep apnea? 3) Is apnea a factor independent from obesity in the development of insulin resistance? Obese middle-aged men with sleep apnea were first compared with nonapneic age- and body mass index (BMI)-matched obese and age-matched lean men. All subjects were monitored in the sleep laboratory for 4 consecutive nights. We obtained simultaneous indexes of sleep, sleep stages, and sleep apnea, including apnea/hypopnea index and percent minimum oxygen saturation. The sleep apneic men had higher plasma concentrations of the adipose tissue-derived hormone, leptin, and of the inflammatory, fatigue-causing, and insulin resistance-producing cytokines tumor necrosis factor-alpha and interleukin-6 than nonapneic obese men, who had intermediate values, or lean men, who had the lowest values. Because these findings suggested that sleep apneics might have a higher degree of insulin resistance than the BMI-matched controls, we studied groups of sleep-apneic obese and age- and BMI-matched nonapneic controls in whom we obtained computed tomographic scan measures of total, sc, and visceral abdominal fat, and additional biochemical indexes of insulin resistance, including fasting plasma glucose and insulin. The sleep apnea patients had a significantly greater amount of visceral fat compared to obese controls (<0.05) and indexes of sleep disordered breathing were positively correlated with visceral fat, but not with BMI or total or sc fat. Furthermore, the biochemical data confirmed a higher degree of insulin resistance in the group of apneics than in BMI-matched nonapneic controls. We conclude that there is a strong independent association among sleep apnea, visceral obesity, insulin resistance and hypercytokinemia, which may contribute to the pathological manifestations and somatic sequelae of this condition.

Analysis of Variance↗

Sleep deprivation effects on the activity of the hypothalamic-pituitary-adrenal and growth axes: potential clinical implications.

OBJECTIVES: Although several studies have shown that sleep deprivation is associated with increased slow wave sleep during the recovery night, the effects of sleep deprivation on cortisol and growth hormone (GH) secretion the next day and recovery night have not been assessed systematically. We hypothesized that increased slow wave sleep postsleep deprivation is associated with decreased cortisol levels and that the enhanced GH secretion is driven by the decreased activity of the HPA axis. DESIGN AND SUBJECTS: After four consecutive nights in the Sleep Laboratory, 10 healthy young men were totally deprived of sleep during the fifth night, and then allowed to sleep again on nights six and seven. Twenty-four hour blood sampling was performed serially every 30 minutes on the fourth day, immediately following the previous night of sleep and on the sixth day, immediately after sleep deprivation. MEASUREMENT: Eight-hour sleep laboratory recording, including electroencephologram, electro-oculogram and electromyogram. Plasma cortisol and GH levels using specific immunoassay techniques. RESULTS: Mean plasma and time-integrated (AUC) cortisol levels were lower during the postdeprivation nighttime period than on the fourth night (P < 0.05). Pulsatile analysis showed significant reduction of both the 24 h and daytime peak area (P < 0.05) and of the pulse amplitude (P < 0.01), but not of the pulse frequency. Also, the amount of time-integrated GH was significantly higher for the first 4 h of the postdeprivation night compared to the predeprivation night (P < 0.05). Cross-correlation analyses between the absolute values of the time-series of each hormone value and percentage of each sleep stage per half hour revealed that slow wave sleep was negatively correlated with cortisol and positively correlated with GH with slow wave sleep preceding the secretion of these hormones. In contrast, indices of sleep disturbance, i.e. wake and stage 1 sleep, were positively correlated with cortisol and negatively correlated with GH. CONCLUSION: We conclude that sleep deprivation results in a significant reduction of cortisol secretion the next day and this reduction appears to be, to a large extent, driven by the increase of slow wave sleep during the recovery night. We propose that reduction of CRH and cortisol secretion may be the mechanism through which sleep deprivation relieves depression temporarily. Furthermore, deep sleep has an inhibitory effect on the HPA axis while it enhances the activity of the GH axis. In contrast, sleep disturbance has a stimulatory effect on the HPA axis and a suppressive effect on the GH axis. These results are consistent with the observed hypocortisolism in idiopathic hypersomnia and HPA axis relative activation in chronic insomnia. Finally, our findings support previous hypotheses about the restitution and immunoenhancement role of slow wave (deep) sleep.

Adult↗

Sleep and its disorders.

Sleep disorders are very prevalent in the general population and are associated with significant medical, psychological, and social disturbances. Insomnia is the most common. When chronic, it usually reflects psychological/behavioral disturbances. Most insomniacs can be evaluated in an office setting, and a multidimensional approach is recommended, including sleep hygiene measures, psychotherapy, and medication. The parasomnias, including sleepwalking, night terrors, and nightmares, have benign implications in childhood but often reflect psychopathology or significant stress in adolescents and adults and organicity in the elderly. Excessive daytime sleepiness is typically the most frequent complaint and often reflects organic dysfunction. Narcolepsy and idiopathic hypersomnia are chronic brain disorders with an onset at a young age, whereas sleep apnea is more common in middle age and is associated with obesity and cardiovascular problems. Therapeutic naps, medications, and supportive therapy are recommended for narcolepsy and hypersomnia; continuous positive airway pressure, weight loss, surgery, and oral devices are the common treatments for sleep apnea.

Adolescent↗

Circadian interleukin-6 secretion and quantity and depth of sleep.

Patients with pathologically increased daytime sleepiness and fatigue have elevated levels of circulating interleukin-6 (IL-6). The latter is an inflammatory cytokine, which causes sickness manifestations, including somnolence and fatigue, and activation of the hypothalamic-pituitary-adrenal axis. In this study, we examined: 1) the relation between serial measurements of plasma IL-6 and quantity and depth of sleep, evaluated by polysomnography; and 2) the effects of sleep deprivation on the nyctohemeral pattern of IL-6 secretion. Eight healthy young male volunteers were sampled for 24 h twice, at the baseline state, after a normal night's sleep and after total overnight sleep deprivation. At the baseline state, IL-6 was secreted in a biphasic circadian pattern with two nadirs at 0800 and 2100 and two zeniths at 1900 and 0500 (P < 0.01). The baseline amount of sleep correlated negatively with the overall daytime secretion of the cytokine (P < 0.05). Also, depth of sleep at baseline correlated negatively with the postdeprivation increase of daytime secretion of IL-6 (P < 0.05). Sleep deprivation changed the temporal pattern of circadian IL-6 secretion but not the overall amount. Indeed, during the post-deprivation period, the mean daytime (0800-2200 h) levels of IL-6 were significantly higher (P < 0.05), whereas the nighttime (2200-0600 h) levels were lower than the predeprivation values. Thus, sleep-deprived subjects had daytime oversecretion and nighttime under-secretion of IL-6; the former might be responsible for their daylong somnolence and fatigue, the latter for the better quality (depth) of their sleep. These data suggest that a good night's sleep is associated with decreased daytime secretion of IL-6 and a good sense of well-being and that good sleep is associated with decreased exposure of tissues to the proinflammatory and potentially detrimental actions of IL-6. Sleep deprivation increases daytime IL-6 and causes somnolence and fatigue during the next day, whereas postdeprivation decreases nighttime IL-6 and is associated with deeper sleep.

Adult↗

Obesity without sleep apnea is associated with daytime sleepiness.

BACKGROUND: Daytime sleepiness and fatigue is a frequent complaint of obese patients even among those who do not demonstrate sleep apnea. OBJECTIVE: To assess in the sleep laboratory whether obese patients without sleep apnea are sleepier during the day compared with healthy controls with normal weight. METHODS: Our sample consisted of 73 obese patients without sleep apnea, upper airway resistance syndrome, or hypoventilation syndrome who were consecutively referred for treatment of their obesity and 45 controls matched for age. All patients and healthy controls were monitored in the sleep laboratory for 8 hours at night and at 2 daytime naps, each for 1 hour the following day. RESULTS: Obese patients compared with controls were sleepier during the day and their nighttime sleep was disturbed. During both naps, sleep latency, wake time after onset of sleep, and total wake time were significantly lower, whereas the percentage of sleep time was significantly higher in obese patients compared with controls. In contrast, during the nighttime testing, obese patients compared with controls demonstrated significantly higher wake time after onset of sleep, total wake time, and lower percentage of sleep time. An analysis of the relation between nighttime and daytime sleep suggested that daytime sleepiness in obese patients is a result of a circadian abnormality rather than just being secondary to nighttime sleep disturbance. CONCLUSIONS: Daytime sleepiness is a morbid characteristic of obese patients with a potentially significant impact on their lives and public safety. Daytime sleepiness in individuals with obesity appears to be related to a metabolic and/or circadian abnormality of the disorder.

Adolescent↗

Chronic insomnia and activity of the stress system: a preliminary study.

The aim of this study was to assess whether there is an association between chronic insomnia and the activity of the stress system. Fifteen young adult insomniacs (<40 years) were studied. After an adaptation night, each subject was recorded in the sleep laboratory for three consecutive nights. During this period, 24-hour urine specimens were collected for measurements of urinary free cortisol (UFC), catecholamines, and growth hormone (GH). The 24-hour UFC levels were positively correlated with total wake time (p=0.05). In addition, 24-hour urinary levels of catecholamine metabolites, DHPG, and DOPAC were positively correlated with percent stage 1 sleep (p<0.05) and wake time after sleep onset (WTASO) (p<0.05). Norepinephrine tended to correlate positively with percent stage 1 sleep (p=0.063) and WTASO (p=0.074), and negatively with percent slow-wave sleep (p=0.059). Twenty-four-hour urinary GH excretion was detectable in only three insomniacs, two of whom had low indices of sleep disturbance. We conclude that, in chronic insomnia, the activity of both limbs of the stress system (i.e., the HPA axis and the sympathetic system) relates positively to the degree of objective sleep disturbance.

Adult↗

Effects of age on sleep apnea in men: I. Prevalence and severity.

The effects of age on the prevalence of sleep apnea in the general population remain unclear, because previous studies have focused on specific populations. The effects of age on the severity of apnea are unknown. This study was based on a two-stage general random sample of men (aged 20 to 100 yr), consisting of a telephone survey (n = 4,364) and a sleep laboratory evaluation of a survey subsample (n = 741). Obstructive sleep apnea (OSA), based on both sleep laboratory and clinical criteria (apnea/hypopnea index [AHI] > or = 10 and the presence of daytime symptoms) was found in 3.3% of the sample, with its maximum prevalence in the middle age group (45 to 64 yr). Also, based solely on laboratory criteria, the prevalence of OSA (obstructive AHI > or = 20) showed an age distribution similar to that of OSA diagnosed by laboratory and clinical criteria. The prevalence of any type of sleep apnea (central and obstructive) increased monotonically with age. However, central apnea appeared to account for this monotonic relationship with age. Severity of sleep apnea, as indicated by both number of events and minimum oxygen saturation, decreased with age when any sleep apnea criteria were used and when controlling for body mass index (BMI). The study shows that the prevalence of sleep apnea tends to increase with age but that the clinical significance (severity) of apnea decreases. On the basis of these findings, the sleep laboratory criteria used for diagnosis of sleep apnea should be adjusted for age.

Adult↗

Effects of diagnosis on treatment recommendations in chronic insomnia--a report from the APA/NIMH DSM-IV field trial.

The objective of this study was to determine whether sleep specialists and nonspecialists recommend different treatments for different insomnia diagnoses according to two different diagnostic classifications. Two hundred sixteen patients with chronic insomnia at five sites were each interviewed by two clinicians: one sleep specialist and one nonsleep specialist. All interviewers indicated diagnoses using the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV); sleep specialists also indicated diagnoses according to the International Classification for Sleep Disorders (ICSD). Interviewers then indicated how strongly they would recommend each item in a standard list of treatment and diagnostic interventions for each patient. We examined differences in treatment recommendations among the six most common DSM-IV diagnoses assigned by sleep specialists at different sites (n = 192), among the six most common ICSD diagnoses assigned by sleep specialists at different sites (n = 153), and among the six most common DSM-IV diagnoses assigned by nonspecialists at different sites (n = 186). In each analysis, specific treatment and polysomnography recommendations differed significantly for different diagnoses, using either DSM-IV or ICSD criteria. Conversely, different diagnoses were associated with different rank orderings of specific treatment and diagnostic recommendations. Sleep specialist and nonspecialist interviewers each distinguished treatment recommendations among different diagnoses, but in general, nonspecialists more strongly recommended medications and relaxation treatments. Significant site-related differences in treatment recommendations also emerged. Differences in treatment recommendations support the distinction between different DSM-IV and ICSD diagnoses, although they do not provide formal validation. Site-related differences suggest a lack of consensus in how these disorders are conceptualized and treated.

Adolescent↗

Clinical factors contributing to the differential diagnosis of primary insomnia and insomnia related to mental disorders.

OBJECTIVE: Primary insomnia and insomnia related to mental disorders are the two most common DSM-IV insomnia diagnoses, but distinguishing between them is difficult in clinical practice. This analysis was performed to identify clinical factors used by sleep specialists to distinguish primary insomnia from insomnia related to mental disorders. METHOD: Clinicians evaluated 216 patients referred for insomnia at five clinical sites, rated a list of clinical factors judged to contribute to each patient's presentation, and assigned diagnoses. Analysis of variance was performed, with contributing factors as the dependent variable and diagnostic group and clinic location as independent variables. RESULTS: Sleep specialists rated a psychiatric disorder as a stronger factor for insomnia related to mental disorders and rated negative conditioning and sleep hygiene as stronger factors for primary insomnia. However, a psychiatric disorder was rated as a contributing factor for 77% of patients who received a first diagnosis of primary insomnia. CONCLUSIONS: While neither sleep hygiene nor negative conditioning is a diagnostic criterion in DSM-IV, these results support the face validity of these clinical factors distinguishing between primary insomnia and insomnia related to mental disorders. The use of a psychiatric disorder as an inclusion criterion for insomnia related to mental disorders and an exclusion criterion for primary insomnia reinforces a categorical distinction between the two diagnoses, but the contribution of psychiatric symptoms in primary insomnia appears to be a clinically relevant one. These findings suggest the need for studies on the validity of negative conditioning and sleep hygiene in the etiology of primary insomnia, as well as on the significance of psychiatric disorders, especially depression, in primary insomnia.

Adolescent↗

Rapid eye movement sleep correlates with the overall activities of the hypothalamic-pituitary-adrenal axis and sympathetic system in healthy humans.

To assess the association of the overall amount of rapid eye movement (REM) sleep and the activities of the hypothalamic-pituitary-adrenal axis and sympathetic system, we performed polysomnography and measured 24-h urinary free cortisol and catecholamine excretion in 21 healthy adults. After an adaptation night, each subject was recorded in the sleep laboratory for 3 consecutive nights while 24-h urine specimens were collected. Urinary free cortisol, epinephrine, dihydroxyphenylglycol, and dihydroxyphenylacetic acid levels were significantly and positively correlated with the average values of percent REM sleep (P < 0.05). There were no correlations between hormone values and REM latency, other variables of REM distribution, or REM density, an index of phasic activity during REM sleep. The positive correlations between stress system activity and REM sleep are consistent with hormonal and sleep alterations in melancholic depression, a state characterized by increased cortisol and catecholamine secretion.

Adult↗

Elevation of plasma cytokines in disorders of excessive daytime sleepiness: role of sleep disturbance and obesity.

Excessive daytime sleepiness (EDS) and fatigue are frequent symptoms in the general population and the chief complaint of the majority of patients at Sleep Disorders Centers. There is evidence that the inflammatory cytokines tumor necrosis factor-alpha (TNF alpha), interleukin-1beta (IL-1beta), and IL-6 are involved in physiological sleep regulation and that their administration to humans is associated with sleepiness and fatigue. To explore whether plasma levels of TNF alpha, IL-1beta, and IL-6 are elevated in patients with EDS, we measured morning plasma levels of TNF alpha, IL-1beta, and IL-6 in 12 sleep apneics, 11 narcoleptics, 8 idiopathic hypersomniacs, and 10 normal controls. TNF alpha was significantly elevated in sleep apneics and narcoleptics compared to that in normal controls (P < 0.001 and P = 0.001, respectively). Plasma IL-1beta concentrations were not different between sleep disorder patients and controls, whereas IL-6 was markedly and significantly elevated in sleep apneics compared to that in normal controls (P = 0.028). The primary factor influencing TNF alpha values was the degree of nocturnal sleep disturbance, whereas the primary determinant for IL-6 levels was the body mass index. Our findings suggest that TNF alpha and IL-6 might play a significant role in mediating sleepiness and fatigue in disorders of EDS in humans.

Adult↗

Relationship of sleep abnormalities to patient genotypes in Prader-Willi syndrome.

To assess whether sleep abnormalities are related to the genetic abnormalities in Prader-Willi Syndrome (PWS), we performed polysomnographic studies (nighttime and daytime) and determined the chromosome 15 genotypes in eight patients with PWS. Four patients demonstrated sleep onset REM periods (SOREM), and five met the objective polysomnographic criteria for severe or moderate excessive daytime sleepiness (EDS). Three of the four patients with SOREM displayed a paternally derived deletion of chromosome 15q11-q13, whereas the fourth exhibited maternal uniparental heterodisomy in this chromosomal region (UPD). Two of the four patients that did not display SOREM carried paternally derived deletions; the remaining two demonstrated UPD. Four of the five patients with EDS displayed paternal deletions, and the fifth exhibited UPD. One of three patients without evidence of EDS demonstrated paternal deletion; the remaining two showed UPD. Although neither EDS nor SOREM was not consistently associated with a specific genetic abnormality, these phenotypes may be more common in patients with paternal deletions than in those UPD. Sleep abnormalities in PWS cannot be explained by a single genetic model.

Adolescent↗