Plasma leptin in men and women with seasonal affective disorder and in healthy matched controls.

Seasonal affective disorder (SAD) is a specific clinical entity characterized by recurrent episodes of depression, which typically occur during the winter with periods of remission during the spring and summer. These depression episodes are accompanied by hyperphagia with cravings for carbohydrates and moderate weight gain, and usually respond to light therapy. We examined potential relationships between leptin, a hormone known to affect appetite and weight regulation, and seasonal changes in mood and appetite by measuring plasma leptin, clinical severity of depression, appetite scores, and body mass index (BMI) in 19 women and 8 men with SAD and matched controls (20 women and 8 men) in the summer and winter.

Glucocorticoid replacement is permissive for rapid eye movement sleep and sleep consolidation in patients with adrenal insufficiency.

There is a well described temporal relation between hormonal secretion and sleep phase, with hormones of the hypothalamic-pituitary-adrenal (HPA) axis possibly playing a role in determining entry into and duration of different sleep stages. In this study sleep features were studied in primary Addison's patients with undetectable levels of cortisol treated in a double blind, randomized, cross-over fashion with either hydrocortisone or placebo supplementation. We found that REM latency was significantly decreased in Addison's patients when receiving hydrocortisone at bedtime, whereas REM sleep time was increased.

Summer and winter patterns of seasonality in Chinese college students: a replication.

The goal of this study is to replicate an earlier epidemiological finding of seasonal changes in mood and behavior among Chinese medical students using an independent study population. Three hundred nineteen college students were surveyed with a Chinese version of the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Beck Depression Inventory (BDI) in Jining, China, during March of 1996. The frequency of seasonal patterns and prevalence rates of seasonal affective disorder (SAD) were estimated and compared with data from the medical student survey conducted in the same city.

Seasonal variations in mood and behavior among Chinese medical students.

Objective: The goal of this study was to estimate the frequency of seasonal variations in mood and behavior among Chinese medical students.

Method: A total of 1,358 medical students were surveyed with Chinese versions of the Seasonal Pattern Assessment Questionnaire and the Beck Depression Inventory in Jining, China.

Results: The mean global seasonality score was 8.

Lack of relationship between menstrual cycle phase and mood in a sample of women with rapid cycling bipolar disorder.

Background: Women are overrepresented in samples of patients with rapid cycling bipolar disorder (RCBD). To explore whether menstrually related mood changes might account for this gender difference, we studied the relationship between menstrual cycle phase and mood in a sample of premenopausal women with rapid cycling bipolar disorder (RCBD).

Methods: Twenty-five women with RCBD completed daily self-rating forms indicating their mood and days of menstruation for a minimum of three months.

The role of genetic factors in the etiology of seasonal affective disorder and seasonality.

The study of the genetic basis of seasonal affective disorder (SAD), a condition where depressions in fall and winter alternate with nondepressed periods in the spring and summer, has recently received attention. The data on the genetics of seasonal affective disorders are of three types: 1. Familiality: Studies on the prevalence of psychiatric disorders among relatives of patients with SAD suggested a familial contribution to the development of SAD; 2.

Gender differences in glycosylated hemoglobin levels in seasonal affective disorder patients and controls.

Seasonal affective disorder (SAD) has been shown to manifest different symptoms in female and male patients. Specifically, women with SAD have been shown to have greater increases in overeating, weight gain, and increased sleep as compared with their male counterparts. Given these dietary changes, we predicted that female SAD patients would exhibit increased glycosylated hemoglobin (HbA1) levels, indicative of chronically elevated glucose levels.

Relationship between social rhythms and mood in patients with rapid cycling bipolar disorder.

Disruptions in the sleep-wake cycle frequently characterize affective illness and have led to a number of theories linking sleep-wake and/or circadian rhythm disturbance to affective illness. Recently, researchers have expanded these chronobiological theories to include the role of lifestyle regularity, or daily social rhythms. In this study, the Social Rhythm Metric (SRM) was used to explore the relationship between social rhythms and mood in patients with rapid cycling bipolar disorder and to compare the social rhythms of patients with those of healthy control subjects.

Validation of the hypomania interview guide-seasonal affective disorder (HIGH-SAD) version in patients with rapid cycling bipolar disorder.

We validated the Hypomania Interview Guide-Seasonal Affective Disorder version (HIGH-SAD) in patients with rapid cycling bipolar disorder (RCBD). Fourteen outpatients were rated on six separate occasions (total = 84 visits). On each visit the patients were rated with the HIGH-SAD and the Young Mania Rating Scale (YMRS) in a counterbalanced order.

Greater improvement in summer than with light treatment in winter in patients with seasonal affective disorder.

Objective: The authors sought to compare the degree of mood improvement after light treatment with mood improvement in the subsequent summer in patients with seasonal affective disorder.

Method: By using the Seasonal Affective Disorder Version of the Hamilton Depression Rating Scale, the authors rated 15 patients with seasonal affective disorder on three occasions: during winter when the patients were depressed, during winter following 2 weeks of light therapy, and during the following summer. They compared the three conditions by using Friedman's analysis of variance and the Wilcoxon signed ranks test.

Serotonin 1A receptors, melatonin, and the proportional control thermostat in patients with winter depression.

Background: In patients with seasonal affective disorder, light treatment lowers core temperature during sleep in proportion to its antidepressant efficacy. The regulation of the level of core temperature during sleep is linked with a proportional control thermostat in the central nervous system whose operation appears abnormal in patients with seasonal affective disorder. Because both melatonin and serotonin 1A receptor activation also lower core temperature, we investigated the relationship between (1) endogenous melatonin and core temperature profiles, (2) the proportional control thermostat, and (3) the core hypothermic response to the serotonin 1A receptor partial agonist ipsapirone hydrochloride in patients with seasonal affective disorder and healthy controls.

Effects of tryptophan depletion vs catecholamine depletion in patients with seasonal affective disorder in remission with light therapy.

Background: Although hypotheses about the therapeutic mechanism of action of light therapy have focused on serotonergic mechanisms, the potential role, if any, of catecholaminergic pathways has not been fully explored.

Methods: Sixteen patients with seasonal affective disorder who had responded to a standard regimen of daily 10000-lux light therapy were enrolled in a double-blind, placebo-controlled, randomized crossover study. We compared the effects of tryptophan depletion with catecholamine depletion and sham depletion.

Treatment of rapidly cycling bipolar patient by using extended bed rest and darkness to stabilize the timing and duration of sleep.

Background: The modern practice of using artificial light to extend waking activities into the nighttime hours might be expected to precipitate or exacerbate bipolar illness, because it has been shown that modifying the timing and duration of sleep can induce mania in susceptible individuals. With this possibility in mind, we treated a patient with rapidly cycling bipolar illness by creating an environment that was likely to increase and to stabilize the number of hours that he slept each night.

Methods: We asked the patient to remain at bed rest in the dark for 14 hours each night (later this was gradually reduced to 10 hours).

Homeostatic regulation of REM sleep in humans during extended sleep.

Benington and Heller (1994) recently proposed a sleep-dependent model for the homeostatic control of REM sleep in which the amount of REM sleep propensity discharged in each bout of REM sleep affects the timing of the subsequent REM episode. Consistent with their hypothesis, they reported that in rats the duration of a REM episode was positively correlated with the duration of the succeeding NREM episode and not with the duration of the preceding NREM episode. To assess this hypothesis in humans, we used 308 sleep records from 11 subjects who remained at bedrest in the dark and slept ad libitum during 14-hour periods each night for 4 weeks.

Role of serotonin transporter promoter repeat length polymorphism (5-HTTLPR) in seasonality and seasonal affective disorder.

Seasonal variations in mood and behavior (seasonality) and seasonal affective disorder (SAD) have been attributed to seasonal fluctuations in brain serotonin (5-HT). the short (s), as opposed to the long (l), allele of the 5-HT transporter linked polymorphism (5-HTTLPR) has been associated with neuroticism and depression. We hypothesized that this short allele would also be associated with SAD and with higher levels of seasonality.

Disruption of the activity-rest cycle by MAOI treatment: dependence on light and a secondary visual pathway to the circadian pacemaker.

The disruptive effects on the activity-rest cycle of the monoamine oxidase inhibitor (MAOI) clorgyline and of continuous light were examined in Syrian hamsters. When administered in dim and moderate light intensities, clorgyline delayed the daily onset of wheel-running. When administered in bright light, it dissociated the circadian rhythm of wheel-running.

Effect of seasonal changes in daylength on human neuroendocrine function.

The circadian pacemaker imposes stereotypic patterns of daily variation on the activity of human neuroendocrine systems. In a number of cases, these patterns exhibit waveforms that are characterized by distinct diurnal and nocturnal periods with relatively discrete transitions between them (corresponding to a biological day, a biological dusk, a biological night, and a biological dawn). In humans, for example, diurnal periods of absence of melatonin secretion, low prolactin secretion, and falling levels of cortisol alternate with nocturnal periods of active melatonin secretion, high prolactin secretion and rising levels of cortisol.

Lack of seasonal variation of symptoms in patients with chronic fatigue syndrome.

Several of the symptoms involved in chronic fatigue syndrome (CFS) such as fatigue, hypersomnia, hyperphagia, weight gain, and mood show seasonal variations in the general population. The aim of this study was to investigate whether patients with CFS experience seasonal fluctuations in these symptoms as well. Seasonal variation of symptoms was assessed in a group of 41 patients with CFS and 41 controls closely matched for age, gender, and city of residence.

Dynamics of the human EEG during prolonged wakefulness: evidence for frequency-specific circadian and homeostatic influences.

The electroencephalogram (EEG) of nine healthy individuals was recorded at half-hourly intervals during approximately 40 h of sustained wakefulness in a constant routine protocol. EEG power density in the 0.75-9.

Increase of 5HT and VIP immunoreactivity within the hamster (Mesocricetus auratus) SCN during chronic MAOI treatment.

The effects of chronic treatment with the monoamine oxidase inhibitor (MAOI), clorgyline (CLG; 2 mg/kg per day) on serotonin (5HT) and vasoactive intestinal peptide (VIP) immunoreactivity (IR) within the hamster suprachiasmatic nucleus (SCN) were examined. Optical densities of 5HT IR and VIP IR were increased by MAOI treatment. VIP IR was increased in both the ventrolateral and dorsal regions of the SCN, suggesting that VIP content was increased within both perikarya and terminals of VIP neurons.

Melatonin and seasonal rhythms.

The pineal hormone melatonin plays a ubiquitous role in biology as a chemical mediator of the effects of season on animal physiology and behavior. Seasonal changes in night length (scotoperiod) induce parallel changes in the duration of melatonin secretion (which occurs exclusively at night), so that it is longer in winter and shorter in summer. These changes in duration of nocturnal melatonin secretion, in turn, trigger seasonal changes in behavior.

Effects of leuprolide-induced hypogonadism and testosterone replacement on sleep, melatonin, and prolactin secretion in men.

The possible role of gonadal steroids in regulating sleep and circadian rhythms in humans has received relatively little attention despite the importance of the topic to several clinical syndromes. Pharmacologically induced hypogonadism, with and without gonadal steroid replacement, provides an opportunity to examine these questions within a controlled experimental design. We used leuprolide acetate, with and without testosterone replacement, to study the role of testosterone in the regulation of sleep and of melatonin, PRL, and TSH secretion in men.

Effects of exogenous melatonin administration and withdrawal in five patients with rapid-cycling bipolar disorder.

Background: The ready availability of exogenous melatonin means that its use in patients with mood disorders is probably not uncommon. Nonetheless, few controlled trials of exogenous melatonin in these patients have been conducted.

Method: Five patients with rapid-cycling DSM-III-R bipolar disorder were treated with melatonin 10 mg q.

Seasonal variation in core temperature regulation during sleep in patients with winter seasonal affective disorder.

Nocturnal core temperature during sleep is elevated during depression compared with remission in nonseasonally depressed patients. Similarly, nocturnal core temperature is higher during winter depression compared with remission induced by light treatment in seasonal affective disorder (SAD) patients. We investigated whether nocturnal core temperature in SAD patients naturally becomes lower in summer (during remission) compared with winter (during depression).

Seasonality and pituitary volume.

Pituitary volume in humans has been reported to change size in response to experimental manipulations of photoperiod, and to be increased during an episode of non-seasonal major depression. We wanted to determine whether pituitary volume changes either across the seasons or during an episode of winter depression. Nineteen patients with winter-seasonal affective disorder and 19 sex-, age-, height-, and weight-matched controls underwent magnetic resonance imaging of the pituitary gland in both winter and summer.