Sleep, Hormones, and Circadian Rhythms throughout the Menstrual Cycle in Healthy Women and Women with Premenstrual Dysphoric Disorder

A relationship exists between the sleep-wake cycle and hormone secretion, which, in women, is further modulated by the menstrual cycle. This interaction can influence sleep across the menstrual cycle in healthy women and in women with premenstrual dysphoric disorder (PMDD), who experience specific alterations of circadian rhythms during their symptomatic luteal phase along with sleep disturbances during this time. This review will address the variation of sleep at different menstrual phases in healthy and PMDD women, as well as changes in circadian rhythms, with an emphasis on their relationship with female sex hormones. It will conclude with a brief discussion on nonpharmacological treatments of PMDD which use chronotherapeutic methods to realign circadian rhythms as a means of improving sleep and mood in these women

Adolescent Sleep Behavioral Interventions and Opportunities to Improve Cognitive Functioning: A Call for Action

Sleep is related to cognitive functioning, learning, and brain development in the adolescent population. Recent research indicates a rise in the presence of chronic sleep disorders such as insomnia in adolescents, particularly following the COVID-19 pandemic. Therefore, research on the effectiveness of sleep interventions for adolescents is necessary to guide treatment in adolescents. The authors conducted a systematic review of literature examining research on outcomes of treatment interventions for insomnia on sleep quality and cognitive functioning in adolescents. Results indicate a dearth of research examining effectiveness of treatment in adolescents, particularly in relation to the impact of such treatment on cognitive functioning in adolescents. The following paper provides a brief overview of existing research on treatment of insomnia or related problems including initiating, maintaining and awaking for adolescent populations with a focus on improvement of cognitive functioning within this population. The authors discuss existing barriers to research, emphasize the need to expand sleep research to include cognitive functioning outcomes, and inform best practices for treatment in adolescents following COVID-19. Lastly, the authors propose a call to action encouraging more widespread recognition of the need for research in this area

The relationship of shift work disorder with symptoms of depression, anxiety, and stress

Shift workers commonly suffer from disturbed sleep, which is known to affect mental health in other populations. Shift work disorder (SWD) is characterized by complaints of insomnia and/or excessive daytime sleepiness temporally associated with working non-standard schedules that occur during the usual time for sleep. Few studies have explored the extent to which workers with vs. without SWD experience worse mental health. We administered the Shift Work Disorder Screening Questionnaire to 60 adults engaged in various shift work schedules to categorize workers as being at high or low risk for SWD. Mental health outcomes were measured using the Depression Anxiety Stress Scale-21 (DASS-21). Linear regression was performed for each DASS-21 subscale, adjusting for age, sex, shift type, sleep duration, and frequency of alcohol use. Most participants (55 %) were at high risk for SWD. High-risk participants had higher depressive symptoms than low-risk participants, B = 3.59, 95 % CI [0.54, 6.65], p = .02. The estimated value for those at high risk for SWD corresponded to clinically significant mild depressive symptoms, (M = 13.43), compared to those at low risk, (M = 9.84). High risk for SWD was marginally associated with increased stress symptoms, B = 2.48, 95 % CI [−0.06,5.02], p = .06. Our findings add to the body of evidence that SWD is associated with poor mental health outcomes. Providing interventions specific to the sleep impacts of SWD, including tailored cognitive behavioral therapy for insomnia, may improve shift workers’ mental health

Effects of Continuous Positive Airway Pressure on Body Composition in Individuals with Obstructive Sleep Apnea: A Non-Randomized, Matched Before-After Study

A reciprocal relationship between obesity and obstructive sleep apnea (OSA) likely exists, wherein obesity contributes to OSA, and OSA-related sleep disturbances promote weight gain. It remains unclear whether continuous positive airway pressure (CPAP) affects body composition. We conducted an open-label, parallel-arm, non-randomized, matched before-after study in individuals with OSA who were starting CPAP use (n = 12) and who were not (n = 12) to examine the effects of CPAP on total body composition (via air displacement plethysmography) including fat and fat-free mass. CPAP users (n = 12) were studied at baseline and after 8 weeks of CPAP use, and 12 age- and sex-matched non-CPAP OSA controls were studied at baseline and after an 8 week period. Statistically significant group x time interactions were seen for body weight, fat-free mass, and fat-mass, such that body weight and fat-free mass were increased, and fat mass decreased, at 8-week follow-up in the CPAP group compared to baseline. Body weight and body composition measures were unchanged in the non-CPAP control group. These findings are consistent with prior studies showing CPAP-induced weight gain, and suggest that weight gain observed following CPAP may be driven primarily by increases in fat-free mass. An increase in lean mass (and decrease in fat mass), despite an overall increase in body weight, can be considered a favorable metabolic outcome in response to CPAP use

The variation of sleep, hormones, and body temperature across circadian and menstrual phases

Women report insomnia more frequently than men, though the reasons for this remain unclear. Theories aiming to explain this observation have often focused on the menstrual cycle, and its associated variations in sex hormones, as a causative factor. Circadian rhythms are known to have an influence on sleep, and the expression of circadian physiology may be altered by the menstrual cycle. The aim of the current thesis was to study the interaction between menstrual and circadian processes, with a particular emphasis on how this interaction affects sleep quality, propensity, and organization, as well as body temperature regulation and neuroendocrine hormone secretion. In the first of two studies, we observed a reduction in rapid eye movement (REM) sleep at specific circadian time points during the mid-luteal (ML) phase compared to the mid-follicular phase. Circadian sleep propensity rhythms were unchanged between menstrual phases, despite the raised core body temperature during the ML phase. Subsequent analyses aimed to explore the thermoregulatory system across circadian, menstrual, and sleep-wake states. These results demonstrated that nap episode-dependent peripheral heat loss mechanisms are maintained at a similar level between menstrual phases, which is likely to explain the similarity in observed circadian sleep propensity rhythms. In a second experiment, women diagnosed with premenstrual dysphoric disorder (PMDD) who present with insomnia symptoms were studied as a model, in which their specific luteal phase-associated pathophysiology can be used as a tool to further explore the interaction between menstrual and circadian processes on the expression of sleep. PMDD was found to be associated with an impaired circadian melatonin rhythm, as well as significantly increased nocturnal slow wave sleep (SWS) compared to healthy controls. These results indicate that a chronobiological abnormality in PMDD patients has functional consequences for the expression of subjective sleep perception, objective sleep organization, and possibly the regulation of homeostatic sleep-wake mechanisms. Taken together, evidence presented here suggests that an interaction between the menstrual cycle and the circadian system plays a role in the regulation of sleep in women. Results of the current thesis may be useful in the development of novel therapeutic approaches for the treatment of sleep complaints in the female population.Les femmes rapportent souffrir d'insomnie plus fréquemment que les hommes, mais les raisons expliquant ce constat restent incertaines. Les théories visant à expliquer les causes de cette observation ont généralement mis l'accent sur le cycle menstruel et les variations des niveaux d'hormones sexuelles y étant associé. Les rythmes circadiens sont connus pour avoir une influence sur le sommeil, et l'expression de la physiologie circadienne peut être modifiée par le cycle menstruel. L'objectif de cette thèse était d'étudier l'interaction entre les processus menstruel et circadien, en mettant particulièrement l'accent sur la façon dont cette interaction affecte la qualité, la propension et l'organisation du sommeil, ainsi que la régulation de la température corporelle et la sécrétion de neurohormones. Dans la première des deux études, nous avons observé une réduction du sommeil paradoxal à des moments précis du cycle circadien, et cela, au cours de la période mi-lutéale (ML) comparativement à la période mi-folliculaire. Le rythme circadien de la propension au sommeil n'a pas changé au cours du cycle menstruel en dépit de la température corporelle élevée au cours de la période ML. Les analyses subséquentes visaient à explorer le système thermorégulatoire au cours du cycle circadien, menstruel et de veille-sommeil. Ces analyses ont démontré que les mécanismes de dissipation de la chaleur corporelle durant les siestes sont maintenus à un niveau comparable au cours du cycle menstruel, ce qui pourrait expliquer la similitude des rythmes circadiens de la propension au sommeil. Dans une seconde expérience, des femmes atteintes d'un trouble dysphorique prémenstruel (TDPM) et qui présentaient des symptômes d'insomnie ont été étudiées comme modèle pour explorer plus en détail l'interaction entre les processus menstruel et circadien sur l'expression du sommeil vu leur physiopathologie spécifique à la période lutéale. Le TDPM a été associé à un rythme circadien de la mélatonine altéré, ainsi qu'à une augmentation significative du sommeil lent profond (SLP) nocturne comparativement aux sujets sains. Les résultats indiquent qu'une anomalie chronobiologique chez les patientes souffrant de TDPM a des conséquences fonctionnelles sur la perception subjective et l'organisation objective du sommeil et, possiblement, sur le processus homéostatique de régulation du cycle veille-sommeil. Collectivement, ces résultats suggèrent que l'interaction entre le cycle menstruel et le système circadien joue un rôle dans la régulation du sommeil chez les femmes. Les résultats de cette thèse pourraient être utiles pour le développement de nouvelles approches thérapeutiques pour le traitement des troubles du sommeil chez les femmes

Objective Food Intake in Night and Day Shift Workers: A Laboratory Study

Night shift work is associated with risk of overweight and obesity. In night shift workers, short sleep duration combined with circadian misalignment may contribute to altered food intake regulation, favoring positive energy balance and weight gain. Prior work investigating food intake in shift workers has suffered methodologically due to reliance on subjective self-report for dietary assessment. No study has yet been done to examine the impact of night shift work on food intake in real-life shift workers using objective measures. Female day (n = 12) and night (n = 12) shift workers from a hospital setting participated in a laboratory-based objective food intake assessment. Participants entered the laboratory in the fasted state after awakening from the sleep episode following a final work shift, and underwent an ad libitum 14-item test meal buffet to objectively quantify food choice/intake. Sleep duration (measured via wrist-accelerometry) during the sleep episode before laboratory assessment was significantly longer in day vs. night workers (373.9 ± 127.5 vs. 260.6 ± 102.9 min, p = 0.03). No significant group difference was observed in calories consumed during the test meal (943.08 ± 469.55 vs. 878.58 ± 442.68 kcal, p = 0.74). When expressed as percent of energy consumed, day workers had higher protein consumption vs. night workers (16.03 ± 5.69 vs. 11.82 ± 4.05%; p = 0.05). To our knowledge, this is the first laboratory-based behavioral assessment of food choice/intake in actual night and day shift workers. Although not studied here, work by others has linked protein intake to satiety. This may be a potential pathway placing shift workers at risk for overweight and obesity