Sleep in women across the life cycle from adulthood through menopause

Nightmare distress, insomnia and resilience of nursing staff in the post-pandemic era

Introduction

The pandemic has led to notable psychological challenges among healthcare professionals, including nurses.

Objective

Our aims of this study were to assess insomnia and nightmare distress levels in nurses and investigate their association with mental resilience.

Methods

Nurses participated in an online survey, which included the Nightmare Distress Questionnaire (NDQ), Brief Resilience Scale (BRS) and Athens Insomnia Scale (AIS). Demographic information, such as age, professional experience and gender, was also collected.

Results

The study included 355 female and 78 male nurses. Findings revealed that 61.4% had abnormal AIS scores, 7% had abnormal NDQ scores and 25.4% had low BRS scores. Female nurses had higher AIS and NDQ scores but lower BRS scores compared to males. BRS demonstrated negative correlations with both AIS and NDQ. Multiple regression analysis indicated that NDQ accounted for 24% of the AIS variance, with an additional 6.5% explained by the BRS. BRS acted as a mediator, attenuating the impact of nightmares on insomnia, with gender moderating this relationship.

Conclusions

Nursing staff experienced heightened sleep disturbances during the pandemic, with nightmares and insomnia being prevalent. Nightmares significantly contributed to insomnia, but mental resilience played a vital role in mitigating this effect. Strategies are warranted to address the pandemic's psychological impact on nursing professionals.

Sleep Disorders and Aging in Women

Women of advancing age can suffer from an array of sleep disorders. We review the changes in sleep architecture, the impact of hormonal changes on sleep, and the various sleep disorders in women of advancing age. A focused history in this population should include the temporal relation to menopause and comorbid conditions. Treatment options should involve patient preference and review of current medications and comorbid conditions to optimize sleep in this population.

The effects of hormonal contraceptive use on sleep in women: A systematic review and meta-analysis

Hormonal contraceptives are some of the most widely used medications worldwide, but studies on their effects on sleep are contradictory, with some reporting a sleep-promoting effect, while others a sleep-inhibiting effect. Our objective was, therefore, to undertake a systematic review and meta-analysis of the literature on this subject to try to clarify their effects. A search was conducted in three databases (PubMed, Scopus and Web of Science). Only studies evaluating hormonal contraception use were considered eligible, and both objective and subjective sleep-related outcomes were considered. Individual effect size was calculated for each article, and meta-analyses were performed using a DerSimonian and Laird random effects method. The initial search identified 2076 articles, of which 13 met the criteria for the study after full text evaluation. A total of 33 meta-analyses were performed, three of them related to subjective measures and 30 considering data from polysomnography. The only statistically significant result between contraceptive users and non-contraceptive users was observed in respect of wake after sleep onset, which was 7 min shorter among contraceptive users (-7.12 [-12.80; -1.44]; I²  = 65%; p = 0.01). In conclusion, hormonal contraceptives are not associated with clinically relevant changes in sleep patterns in women.

Social sleepers: The effects of social status on sleep in terrestrial mammals

Social status among group-living mammals can impact access to resources, such as water, food, social support, and mating opportunities, and this differential access to resources can have fitness consequences. Here, we propose that an animal's social status impacts their access to sleep opportunities, as social status may predict when an animal sleeps, where they sleep, who they sleep with, and how well they sleep. Our review of terrestrial mammals examines how sleep architecture and intensity may be impacted by (1) sleeping conditions and (2) the social experience during wakefulness. Sleeping positions vary in thermoregulatory properties, protection from predators, and exposure to parasites. Thus, if dominant individuals have priority of access to sleeping positions, they may benefit from higher quality sleeping conditions and, in turn, better sleep. With respect to waking experiences, we discuss the impacts of stress on sleep, as it has been established that specific social statuses can be characterized by stress-related physiological profiles. While much research has focused on how dominance hierarchies impact access to resources like food and mating opportunities, differential access to sleep opportunities among mammals has been largely ignored despite its potential fitness consequences.

Sleep Disorders and Aging in Women

What are the effects of sleep disturbance and changes of sleep on aging women in the short and long term? Most research that has been done in recent years evaluates how sleep disorders and sleep disturbance may change mortality and outcomes of this population. Many confounding factors may be playing a role, including comorbid conditions. This article reviews sleep disorders including insomnia, circadian sleep-wake rhythm disorders, restless legs syndrome, disorders of hypersomnia, and sleep-disordered breathing in women aged 65 and older; prevalence of these disorders; and recommended treatment options.

Sex differences within sleep in gonadally intact rats

Sleep impacts diverse physiological and neural processes and is itself affected by the menstrual cycle; however, few studies have examined the effects of the estrous cycle on sleep in rodents. Studies of disease mechanisms in females therefore lack critical information regarding estrous cycle influences on relevant sleep characteristics. We recorded electroencephalographic (EEG) activity from multiple brain regions to assess sleep states as well as sleep traits such as spectral power and interregional spectral coherence in freely cycling females across the estrous cycle and compared with males. Our findings show that the high hormone phase of proestrus decreases the amount of nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep and increases the amount of time spent awake compared with other estrous phases and to males. This spontaneous sleep deprivation of proestrus was followed by a sleep rebound in estrus which increased NREM and REM sleep. In proestrus, spectral power increased in the delta (0.5-4 Hz) and the gamma (30-60 Hz) ranges during NREM sleep, and increased in the theta range (5-9 Hz) during REM sleep during both proestrus and estrus. Slow-wave activity (SWA) and cortical sleep spindle density also increased in NREM sleep during proestrus. Finally, interregional NREM and REM spectral coherence increased during proestrus. This work demonstrates that the estrous cycle affects more facets of sleep than previously thought and reveals both sex differences in features of the sleep-wake cycle related to estrous phase that likely impact the myriad physiological processes influenced by sleep.

Neurobiological and Hormonal Mechanisms Regulating Women's Sleep

Sleep is crucial for optimal well-being, and sex differences in sleep quality have significant implications for women's health. We review the current literature on sex differences in sleep, such as differences in objective and subjective sleep measures and their relationship with aging. We then discuss the convincing evidence for the role of ovarian hormones in regulating female sleep, and survey how these hormones act on a multitude of brain regions and neurochemicals to impact sleep. Lastly, we identify several important areas in need of future research to narrow the knowledge gap and improve the health of women and other understudied populations.

Gender differences influence over insomnia in Korean population: A cross-sectional study

STUDY OBJECTIVES

Insomnia is the most common sleep disorder with significant psychiatric/physical comorbidities in the general population. The aim of this study is to investigate whether socioeconomic and demographic factors are associated with gender differences in insomnia and subtypes in Korean population.

METHOD

The present study used data from the nationwide, cross-sectional study on sleep among all Koreans aged 19 to 69 years. The Insomnia Severity Index (ISI) was used to classify insomnia symptoms and their subtypes (cutoff value: 9.5). The Pittsburgh Sleep Quality Index (PSQI), Goldberg Anxiety Scale (GAS) and Patient Health Questionnaire-9 (PHQ-9) were used to measure sleep quality, anxiety and depression.

RESULTS

A total of 2695 participants completed the survey. The overall prevalence of insomnia symptoms was 10.7%, including difficulty in initiating sleep (DIS) (6.8%), difficulty in maintaining sleep (DMS) (6.5%) and early morning awakening (EMA) (6.5%), and these symptoms were more prevalent in women than in men. Multivariate analysis showed that female gender, shorter sleep time and psychiatric complications were found to be independent predictors for insomnia symptoms and subtypes. After adjusting for covariates among these factors, female gender remained a significant risk factor for insomnia symptoms and their subtypes. As for men, low income was related to insomnia.

CONCLUSION

Approximately one-tenth of the sample from the Korean general population had insomnia symptoms. The prevalence of insomnia symptom and the subtypes were more prevalent in women than men. Gender is an independent factor for insomnia symptoms.

Cognitive Behavioral Therapy for Insomnia and Women's Health: Sex as a Biological Variable

Differences in sleep for men and women begin at a very early age, with women reporting poorer sleep and having a higher risk for insomnia compared with men. Women are particularly vulnerable to developing insomnia during times of reproductive hormonal change. Sleep across the woman's lifespan and special treatment considerations for using cognitive behavioral therapy for insomnia (CBT-I) in women will be addressed in this review.

Sleep/Wake Behaviors in Mice During Pregnancy and Pregnancy-Associated Hypertensive Mice

Study Objectives

In humans and other mammals, sleep is altered during pregnancy. However, no studies have been conducted on sleep/wakefulness during pregnancy in mice. In this study, we examined sleep/wakefulness in female C57BL/6 mice during pregnancy. We also examined sleep/wake behaviors in an animal model of preeclampsia, pregnancy-associated hypertensive (PAH) mice, in which increased angiotensin causes hypertension.

Methods

Sleep/wake behaviors of female C57BL/6 and PAH mice were examined based on electroencephalogram (EEG) or electromyogram recordings before, during, and after pregnancy. To examine whether high blood pressure disrupts the integrity of the blood-brain barrier in PAH mice, Evans blue dye was injected intravenously. Angiotensin II receptor blocker (olmesartan)-administered PAH mice and female Tsukuba hypertensive mice were also examined.

Results

C57BL/6 mice showed a decreased total wake time and increased nonrapid eye movement (NREM) sleep time during late pregnancy. Rapid eye movement (REM) sleep time did not change during the course of pregnancy. PAH mice exhibited a general slowing of EEG during late pregnancy and subsequently returned to apparently normal sleep/wakefulness after delivery. All PAH mice exhibited multiple focal leakages of Evans blue dye in the brain. Spike-and-wave discharges were observed in 50% of PAH mice. Olmesartan-administered PAH mice did not show general slowing of EEG. Tsukuba hypertensive mice showed a normal time spent in wakefulness and NREM sleep and a decreased total REM sleep time.

Conclusions

This study showed pregnant-stage-specific changes in sleep/wakefulness in C57BL/6 mice. Furthermore, PAH mice may be useful as an animal model for eclampsia.

Ovarian hormones, sleep and cognition across the adult female lifespan: An integrated perspective

Loss of ovarian function in women is associated with sleep disturbances and cognitive decline, which suggest a key role for estrogens and/or progestins in modulating these symptoms. The effects of ovarian hormones on sleep and cognitive processes have been studied in separate research fields that seldom intersect. However, sleep has a considerable impact on cognitive function. Given the tight connections between sleep and cognition, ovarian hormones may influence selective aspects of cognition indirectly, via the modulation of sleep. In support of this hypothesis, a growing body of evidence indicates that the development of sleep disorders following menopause contributes to accelerated cognitive decline and dementia in older women. This paper draws from both the animal and human literature to present an integrated view of the effects of ovarian hormones on sleep and cognition across the adult female lifespan.

The middle-aged ovariectomized marmoset (Callithrix jacchus) as a model of menopausal symptoms: Preliminary evidence

Menopausal women often suffer from hot flashes and sleep disturbances that significantly impact their quality of life. Both human and animal studies suggest that loss of estrogens during menopause contribute to these symptoms. In the female rat, both core body temperature (CBT) and sleep are sensitive to 17β-estradiol (E2) levels, but important differences between the rat and the human patterns limit the interpretation of the results. The sleep and thermoregulation of the common marmoset (Callithrix jacchus) more closely resemble human patterns. However, no study to date has examined whether E2 influences sleep and thermoregulation in this species. The main goal of the present study was to investigate the suitability of the ovariectomized (OVX) marmoset for studying two major menopausal symptoms experienced by women, sleep disturbance and thermodysregulation. Two middle-aged OVX marmosets (6years old) were implanted with a telemeter that records electroencephalograms (EEG), electromyograms (EMG), and CBT. Sleep patterns and CBT were recorded under baseline, two E2 replacement (6 and 12μg/kg/day, p.o.) conditions and two E2 withdrawal conditions. Relative to both baseline and withdrawal, high E2 replacement was associated with lower nighttime CBT. In addition, fewer nighttime arousals were observed under low E2 replacement compared to baseline. Higher delta power was observed under both E2 replacement conditions suggesting enhanced sleep quality. These preliminary results suggest that E2 modulates sleep and thermoregulation in the OVX marmoset, making it a promising model for studying menopausal symptoms.

Sex differences in sleep: impact of biological sex and sex steroids

Men and women sleep differently. While much is known about the mechanisms that drive sleep, the reason for these sex differences in sleep behaviour is unknown and understudied. Historically, women and female animals are underrepresented in studies of sleep and its disorders. Nevertheless, there is a growing recognition of sex disparities in sleep and rhythm disorders. Women typically report poorer quality and more disrupted sleep across various stages of life. Findings from clinical and basic research studies strongly implicate a role for sex steroids in sleep modulation. Understanding how neuroendocrine mediators and sex differences influence sleep is central to advancing our understanding of sleep-related disorders. The investigation into sex differences and sex steroid modulation of sleep is in its infancy. Identifying the mechanisms underlying sex and gender differences in sleep will provide valuable insights leading to tailored therapeutics that benefit each sex. The goal of this review is to discuss our current understanding of how biological sex and sex steroids influence sleep behaviour from both the clinical and pre-clinical perspective.

Gender Differences in the Response to Impaired Sleep in Adults with Diabetes

This study analyzed cross-sectional data to examine gender differences in the association of sleep quality and daytime sleepiness with mood and functional outcomes in adults with type 2 diabetes (T2DM). Measures included demographic and clinical data as well as scales that measured subjective daytime sleepiness, sleep quality, mood disturbances, and functional outcomes. The majority of the sample (N = 116) had poor sleep quality and was subjectively sleepy. We observed in males and females significantly different associative patterns between the predictor variables of daytime sleepiness and sleep quality and the outcome variables of mood and functional outcome. There was no significant difference in daytime sleepiness or impaired sleep quality between men and women with T2DM; however, there was a difference in the expression of impaired sleep on mood and functional outcomes between genders.

Actigraphy-defined measures of sleep and movement across the menstrual cycle in midlife menstruating women: Study of Women's Health Across the Nation Sleep Study

OBJECTIVE

This study aims to evaluate patterns in actigraphy-defined sleep measures across the menstrual cycle by testing the hypothesis that sleep would be more disrupted in the premenstrual period (ie, within the 14 d before menses).

METHODS

A community-based longitudinal study of wrist actigraphy-derived sleep measures was conducted in 163 (58 African American, 78 white, and 27 Chinese) late-reproductive-age (mean [SD], 51.5 [2.0] y) women from the Study of Women's Health Across the Nation Sleep Study. Daily measures of sleep (sleep efficiency [%] and total sleep time [minutes]) and movement during sleep (mean activity score [counts]) were characterized using wrist actigraphy across a menstrual cycle or 35 days, whichever was shorter. Data were standardized to 28 days to account for unequal cycle lengths and divided into four weekly segments for analyses.

RESULTS

Sleep efficiency declined gradually across the menstrual cycle, but the decline became pronounced on the fourth week (the premenstrual period). Compared with the third week, sleep efficiency declined by 5% (P < 0.0001) and mean total sleep time was 25 minutes less (P = 0.0002) on the fourth week. We found no significant differences between the mean for the second week and the mean for the third week. The association of weekly segments with sleep efficiency or total sleep time was modified by sociodemographic and lifestyle factors, including body mass index, race, study site, financial strain, marital status, and smoking.

CONCLUSIONS

Among late-reproductive-age women, sleep varies systematically across the menstrual cycle, including a gradual decline in sleep efficiency across all weeks, with a more marked change premenstrually during the last week of the menstrual cycle. These sleep changes may be modified by altering lifestyle factors.

Gonadal steroid modulation of sleep and wakefulness in male and female rats is sexually differentiated and neonatally organized by steroid exposure

The paucity of clinical and preclinical studies investigating sex differences in sleep has resulted in mixed findings as to the exact nature of these differences. Although gonadal steroids are known to modulate sleep in females, less is known about males. Moreover, little evidence exists concerning the origin of these sex differences in sleep behavior. Thus, the goal of this study was to directly compare the sensitivity of sleep behavior in male and female Sprague Dawley rats to changes in the gonadal steroid milieu and to test whether the sex differences in sleep are the result of brain sexual differentiation or differences in circulating gonadal steroids. Here we report the magnitude of change in sleep behavior induced by either estradiol (E2) or testosterone (T) was greater in females compared with males, suggesting that sleep behavior in females is more sensitive to the suppressive effects of gonadal steroids. Furthermore, we demonstrated that the organizational effects of early gonadal steroid exposure result in male-like responsivity to gonadal steroids and directly alter the activity of the ventrolateral preoptic area (VLPO), an established sleep-promoting nucleus, in adult masculinized females. Moreover, the nonaromatizable androgen dihydrotestosterone did not suppress sleep in either males or females, suggesting that the T-mediated effect in females was due to the aromatization of T into E2. Together our data suggest that, like sex behavior, sex differences in sleep follow the classical organizational/activational effects of gonadal steroids.

A population-based survey of sleep disturbances in middle-aged women--associations with health, health related quality of life and health behavior

OBJECTIVE

To evaluate the prevalence of sleep disturbances and the contributing factors in middle-aged women.

METHODS

In a cross-sectional design of the long-term, prospective follow-up study project of 1278 families from a random population sample, the mothers of 15 year-olds were asked to fill in a questionnaire about sleep, health, health related quality of life, and health behavior.

RESULTS

Quality of sleep was reported by 32% of women as good, 43% quite good, 12% average, 10% quite poor and 3% as poor. The most frequent sleep disturbance was awakenings in the night, which 60% of the women experienced at least once a week. Difficulty falling asleep and waking too early in the morning were reported as a weekly occurrence by 16% and 20%, respectively. Morning sleepiness was experienced by 42% and daytime sleepiness by 32%. Chronic diseases and use of medications was associated with various sleep disturbances. Both somatic and mental symptoms increased the risk for sleep disturbances.

CONCLUSIONS

Almost one-quarter of middle-aged women is dissatisfied with their quality of sleep. Women who have chronic disease or use of medications for basic diseases often suffer from sleep disturbance, which is also associated with the health related quality of life. Further analysis of the risk factors is needed to improve the sleep health of middle-aged women.

Sleep and Women's Health

Sex differences in sleep begin at a very early age and women report poorer sleep quality and have higher risk for insomnia than do men. Sleep may be affected by variation in reproductive hormones, stress, depression, aging, life/role transitions, and other factors. The menstrual cycle is associated with changes in circadian rhythms and sleep architecture. Menstruating women (even without significant menstrual-related complaints) often report poorer sleep quality and greater sleep disturbance during the premenstrual week compared to other times of her menstrual cycle. In addition to these sleep disturbances, women with severe premenstrual syndrome often report more disturbing dreams, sleepiness, fatigue, decreased alertness and concentration during the premenstrual phase. Sleep disturbances are also commonly reported during pregnancy and increase in frequency and duration as the pregnancy progresses. The precipitous decline in hormones and unpredictable sleep patterns of the newborn contribute to and/or exacerbate poor sleep and daytime sleepiness during the early postpartum period. Insomnia is also among the most common health complaints that are reported by perimenopausal women. Women are particularly vulnerable to developing insomnia disorder during these times of reproductive hormonal change. In this review, we present a discussion on the most relevant and recent publications on sleep across the woman's lifespan, including changes in sleep related to menstruation, pregnancy, postpartum, and the menopausal transition. Treatment for sleep disturbances and insomnia disorder and special considerations for treating women will also be discussed.

Sleep, rhythms, and the endocrine brain: influence of sex and gonadal hormones

While much is known about the mechanisms that underlie sleep and circadian rhythms, the investigation into sex differences and gonadal steroid modulation of sleep and biological rhythms is in its infancy. There is a growing recognition of sex disparities in sleep and rhythm disorders. Understanding how neuroendocrine mediators and sex differences influence sleep and biological rhythms is central to advancing our understanding of sleep-related disorders. While it is known that ovarian steroids affect circadian rhythms in rodents, the role of androgen is less understood. Surprising findings that androgens, acting via androgen receptors in the master "circadian clock" within the suprachiasmatic nucleus, modulate photic effects on activity in males point to novel mechanisms of circadian control. Work in aromatase-deficient mice suggests that some sex differences in photic responsiveness are independent of gonadal hormone effects during development. In parallel, aspects of sex differences in sleep are also reported to be independent of gonadal steroids and may involve sex chromosome complement. This a summary of recent work illustrating how sex differences and gonadal hormones influence sleep and circadian rhythms that was presented at a Mini-Symposium at the 2011 annual meeting of the Society for Neuroscience.

Forced sex: a critical factor in the sleep difficulties of young Australian women

The prevalence of forced sex and its contribution to sleep difficulties among young Australian women aged 24-30 years (n=9,061) was examined using data from the 2003 Australian Longitudinal Study of Women's Health. The lifetime prevalence of reported forced sex was 8.7%. Significantly higher levels of recurrent sleep difficulties, prescription sleep medication, clinical depression, anxiety disorder, self-harm, and substance use, as well as lower socioeconomic status (SES) indicators, were reported by the forced sex group compared to the no forced sex group. Hierarchical logistic regression revealed the high odds (OR=1.95, CI=1.66-2.26) of recurrent sleep difficulty in such women becomes partially attenuated, but remains statistically significant, after adjusting for key psychological, SES, and behavioral variables. Clinical implications for primary care providers and sleep specialists are discussed. Sleep difficulties are highly prevalent and affect more than 30% of those seeking primary health care (Kushida et al., 2005). They negatively impact on the way a person feels and functions (Dinges et al., 1997) and make a significant contribution to accidents, health care costs, and problems at work (Roth, 2005).

Menopause and Mental Well-Being: Timing of Symptoms and Timing of Hormone Treatment

In the aftermath of the Women's Health Initiative studies, both the clinical and basic science communities had to sort out divergent results among experimental findings, observational data and randomized controlled trials in order to establish a shared analysis. The scientific community formally debates the role of different HRT formulations, hormone doses, time of treatment initiation since the menopause and the age of treated women. Basic scientists demonstrated that the multiple neuroprotective effects of estrogen on brain cells may induce a differential biological response according to the time of treatment. Progesterone (but not all synthetic progestins) also has pivotal neuroactive functions in animal models of reproductive aging. Additionally, epidemiological surveys provide information regarding the detrimental role of hypogonadism on mental well-being. The present article briefly summarizes current evidence supporting the neuroactive role of estrogen, with reference to the clinical finding sustaining the intriguing hypothesis of the early female brain senescence as a highly responsive period to estrogen treatment.

The effects of pain, gender, and age on sleep/wake and circadian rhythm parameters in oncology patients at the initiation of radiation therapy

To date, no studies have evaluated for differences in subjective and objective measures of sleep disturbance in oncology outpatients with and without pain. This descriptive study, recruited 182 patients from 2 radiation therapy (RT) departments at the time of the patient's simulation visit. Approximately 38% of the sample reported moderate to severe pain (ie, worst pain intensity of 6.2 ± 2.4). After controlling for age, patients in pain reported worse sleep quality and more sleep disturbance using the Pittsburgh Sleep Quality Index. With the General Sleep Disturbance Scale, patients in pain reported poorer sleep quality, increased use of sleep medications, and more daytime sleepiness. In addition using an objective measure of sleep disturbance (ie, actigraphy), significant gender × pain interactions were found for sleep onset latency, percentage of time awake at night, wake duration, total sleep time, and sleep efficiency. While no differences were found in female patients, males in pain had worse scores than males without pain. Findings from this study suggest that pain and sleep disturbance are prevalent in oncology outpatients and that a patient's age and gender need to be considered in any evaluation of the relationship between pain and sleep.

PERSPECTIVE

The effects of pain on subjective and objective sleep parameters appear to be influenced by both patients' age and gender.

Postmenopausal hormones and sleep quality in the elderly: a population based study

Background

Sleep disturbance and insomnia are commonly reported by postmenopausal women. However, the relationship between hormone therapy (HT) and sleep disturbances in postmenopausal community-dwelling adults is understudied. Using data from the multicenter Study of Osteoporotic Fractures (SOF), we tested the relationship between HT and sleep-wake estimated from actigraphy.

Methods

Sleep-wake was ascertained by wrist actigraphy in 3,123 women aged 84 ± 4 years (range 77-99) from the Study of Osteoporotic Fractures (SOF). This sample represents 30% of the original SOF study and 64% of participants seen at this visit. Data were collected for a mean of 4 consecutive 24-hour periods. Sleep parameters measured objectively included total sleep time, sleep efficiency (SE), sleep latency, wake after sleep onset (WASO), and nap time. All analyses were adjusted for potential confounders (age, clinic site, race, BMI, cognitive function, physical activity, depression, anxiety, education, marital status, age at menopause, alcohol use, prior hysterectomy, and medical conditions).

Results

Actigraphy measurements were available for 424 current, 1,289 past, and 1,410 never users of HT. Women currently using HT had a shorter WASO time (76 vs. 82 minutes, P = 0.03) and fewer long-wake (≥ 5 minutes) episodes (6.5 vs. 7.1, P = 0.004) than never users. Past HT users had longer total sleep time than never users (413 vs. 403 minutes, P = 0.002). Women who never used HT had elevated odds of SE <70% (OR,1.37;95%CI,0.98-1.92) and significantly higher odds of WASO ≥ 90 minutes (OR,1.37;95%CI,1.02-1.83) and ≥ 8 long-wake episodes (OR,1.58;95%CI,1.18-2.12) when compared to current HT users.

Conclusions

Postmenopausal women currently using HT had improved sleep quality for two out of five objective measures: shorter WASO and fewer long-wake episodes. The mechanism behind these associations is not clear. For postmenopausal women, starting HT use should be considered carefully in balance with other risks since the vascular side-effects of hormone replacement may exceed its beneficial effects on sleep.

Effects of gabapentin on sleep in menopausal women with hot flashes as measured by a Pittsburgh Sleep Quality Index factor scoring model

OBJECTIVE

The aim of this research was to analyze gabapentin's effect on Pittsburgh Sleep Quality Index (PSQI) scores in menopausal women.

METHODS

Secondary analysis of data from a cohort of menopausal women participating in a randomized, double-blind, placebo-controlled trial of gabapentin 300 mg three times daily (TID) for hot flashes. The outcomes of interest were PSQI global and factor scores at weeks 4 and 12.

RESULTS

Subjects randomized to gabapentin demonstrated improvement in the sleep quality factor score, compared to placebo-treated subjects, at 4 and 12 weeks (p < 0.03). There was also gabapentin-associated improvement in the global PSQI score (p = 0.004) and the sleep efficiency factor score (p = 0.05) at 4 weeks. There was no significant effect of gabapentin on the daily disturbance factor score.

CONCLUSIONS

Gabapentin may improve sleep quality in menopausal women with hot flashes. These results warrant further prospective investigation, with an emphasis on measuring subjective sleep quality and maintenance.

Sleep disturbance in midlife women

Emphasizing midlife women, this review describes sleep and compares self-report sleep data with objective findings from laboratory studies of women. Sleep disturbance is a more prevalent complaint for women than men. Not due to chronologic age per se, it is associated with menopausal symptoms and most importantly with comorbidities and stress. Sleep problems in midlife women should not be attributed only to the menopausal symptom experience and should trigger a clinical evaluation. Assessment guidelines are included.

Relations among menopausal symptoms, sleep disturbance and depressive symptoms in midlife

OBJECTIVES

To investigate the relations among hot flashes, other menopausal symptoms, sleep quality and depressive symptoms in midlife women.

METHODS

A large population-based cross-sectional study of 639 women (ages 45-54 years) consisting of a questionnaire including the Center for Epidemiologic Studies-Depression (CES-D) Scale, demographics, health behaviors, menstrual history, and menopausal symptoms.

RESULTS

After controlling for menopausal status, physical activity level, smoking status and current self-reported health status elevated CES-D score is associated with frequent nocturnal hot flashes, frequent trouble sleeping, experiencing hot flashes, nausea, headaches, weakness, visual problems, vaginal discharge, irritability, muscle stiffness, and incontinence.

CONCLUSIONS

The present study found significant links between depressive symptoms and several menopausal symptoms including hot flashes, sleep disturbance, irritability, muscle stiffness, and incontinence after controlling for covariates. These findings suggest that a potential mechanism in which bothersome menopausal symptoms may influence depressed mood during the midlife is through sleep disturbance.

Sleep disorders and medical conditions in women. Proceedings of the Women & Sleep Workshop, National Sleep Foundation, Washington, DC, March 5-6, 2007

Sleep disorders affect women differently than they affect men and may have different manifestations and prevalences. With regard to obstructive sleep apnea (OSA), variations in symptoms may cause misdiagnoses and delay of appropriate treatment. The prevalence of OSA appears to increase markedly after the time of menopause. Although OSA as defined by the numbers of apneas/hypopneas may be less severe in women, its consequences are similar and perhaps worse. Therapeutic issues related to gender should be factored into the management of OSA. The prevalence of insomnia is significantly greater in women than in men throughout most of the life span. The ratio of insomnia in women to men is approximately 1.4:1.0, but the difference is minimal before puberty and increases steadily with age. Although much of the higher prevalence of insomnia in women may be attributable to the hormonal or psychological changes associated with major life transitions, some of the gender differences may result from the higher prevalence of depression and pain in women. Insomnia's negative impact on quality of life is important to address in women, given the high relative prevalence of insomnia as well as the comorbid disorders in this population. Gender differences in etiology and symptom manifestation in narcolepsy remain understudied in humans. There is little available scientific information to evaluate the clinical significance and specific consequences of the diagnosis of narcolepsy in women. Restless legs syndrome (RLS) is characterized by an urge to move the legs or other limbs during periods of rest or inactivity and may affect as much as 10% of the population. This condition is more likely to afflict women than men, and its risk is increased by pregnancy. Although RLS is associated with impaired quality of life, highly effective treatment is available.

Gender, age, and the risk of insomnia

While insomnia is common among men and women and across all age groups, older adults and women experience markedly increased risk for this disorder. Insomnia complaints in adults ≥65 years of age are very common. Foley and colleagues demonstrated in a study of 9,282 older adults (mean age of 74) an insomnia prevalence rate of ∼60%.

Approximately 57% of older adults have sleep complaints (Slide 1). Most of these are associated with comorbid conditions including depressed mood, respiratory problems, or poor physical health. The healthiest members of this population have far fewer sleep complaints.

Estradiol replacement enhances sleep deprivation-induced c-Fos immunoreactivity in forebrain arousal regions of ovariectomized rats

To understand how female sex hormones influence homeostatic mechanisms of sleep, we studied the effects of estradiol (E2) replacement on c-Fos immunoreactivity in sleep/wake-regulatory brain areas after sleep deprivation (SD) in ovariectomized rats. Adult rats were ovariectomized and implanted subcutaneously with capsules containing 17β-E2(10.5 μg; to mimic diestrous E2levels) or oil. After 2 wk, animals with E2capsules received a single subcutaneous injection of 17β-E2(10 μg/kg; to achieve proestrous E2levels) or oil; control animals with oil capsules received an oil injection. Twenty-four hours later, animals were either left undisturbed or sleep deprived by “gentle handling” for 6 h during the early light phase, and killed. E2treatment increased serum E2levels and uterus weights dose dependently, while attenuating body weight gain. Regardless of hormonal conditions, SD increased c-Fos immunoreactivity in all four arousal-promoting areas and four limbic and neuroendocrine nuclei studied, whereas it decreased c-Fos labeling in the sleep-promoting ventrolateral preoptic nucleus (VLPO). Low and high E2treatments enhanced the SD-induced c-Fos immunoreactivity in the laterodorsal subnucleus of the bed nucleus of stria terminalis and the tuberomammillary nucleus, and in orexin-containing hypothalamic neurons, with no effect on the basal forebrain and locus coeruleus. The high E2treatment decreased c-Fos labeling in the VLPO under nondeprived conditions. These results indicate that E2replacement modulates SD-induced or spontaneous c-Fos expression in sleep/wake-regulatory and limbic forebrain nuclei. These modulatory effects of E2replacement on neuronal activity may be, in part, responsible for E2's influence on sleep/wake behavior.

Effect of 17alpha-ethinyl estradiol on active phase rapid eye movement sleep microarchitecture

Estrogen treatment decreases active phase rapid eye movement (REM) sleep in ovariectomized rats. Here we explored further the effect of 17alpha-ethinyl estradiol (17alpha-EE) on active phase REM sleep in ovariectomized rats by analyzing spectral properties and the number and length of REM sleep bouts. The greatest suppression of REM sleep occurred on day 4 of 17alpha-EE treatment, was due to decreases in bout length, and was accompanied by decreased EEG theta power. These results further elucidate 17alpha-EE's effects on REM sleep and provide greater understanding of the mechanisms by which estrogens alter sleep-wakefulness patterns.

Subchronic 17alpha-ethinyl estradiol differentially affects subtypes of sleep and wakefulness in ovariectomized rats

In ovariectomized (OVX) Sprague-Dawley rats, estradiol benzoate (EB) has been reported to decrease rapid eye movement (REM) and non-REM (NREM) sleep during the dark phase for up to 3 days. It is unknown, however, if estrogenic effects on sleep extend beyond 3 days or if other estrogens could induce the same changes. Furthermore, it is unclear whether the increased wakefulness in the dark phase was due to changes in active or quiet wakefulness. Therefore, we examined the effects of daily injections of 17alpha-ethinyl estradiol (EE) for 6 days on sleep and wakefulness in the OVX rat. After 3 days of baseline recording using a telemetric system, rats were administered sesame oil (sc) for 3 days followed by injection with EE (20 mug/rat/day, sc) for 6 days. After treatment, sleep was recorded during hormone withdrawal for an additional 5 days. A few sporadic but statistically significant increases in light phase sleep occurred during the last 3 days of EE treatment. Starting on day 2 of the study, EE caused statistically significant decreases in dark phase REM sleep that were maintained throughout the treatment period and persisted until the 3rd day of hormone withdrawal. During the dark phase, statistically significant decreases in NREM sleep and increases in active wakefulness started on the second day of treatment and abated by the end of treatment. This study demonstrated that EE had similar effects on sleep-wakefulness to EB and demonstrates the utility of telemetric polysomnographic recording of the female OVX rat as a model for understanding the estrogen-induced changes on sleep-wakefulness.

Gender differences in sleep disorders

PURPOSE OF REVIEW

To evaluate recent evidence regarding gender differences in sleep.

RECENT FINDINGS

Women have better sleep quality compared with men, with longer sleep times, shorter sleep-onset latency and higher sleep efficiency. Despite this, women have more sleep-related complaints than men. The amount of slow-wave sleep decreases with age in men and women. Normal physiologic periods, including puberty, menstruation, pregnancy, and menopause, are associated with alterations in sleep patterns. Gender differences in normal sleep may underlie the observed differences in risk of sleep disorders. Studies of insomnia support a female predominance, with increased divergence of prevalence between men and women with older age. Recent findings for the gender differences in obstructive sleep apnea have focused on differences in local neuromuscular reflexes and central ventilatory control. Restless legs syndrome has a slight female predominance, whereas rapid eye movement sleep behavior disorder and Kleine-Levin syndrome are more common in men.

SUMMARY

Gender differences in sleep become apparent after the onset of puberty. Menstrual cycles, pregnancy, and menopause can alter sleep architecture. Gender-related differences in sleep disorders, such as obstructive sleep apnea, insomnia, and restless legs syndrome, include differences in prevalence, pathophysiology, clinical presentation, and response to therapy.

Validation of the Women's Health Initiative Insomnia Rating Scale in a multicenter controlled clinical trial

OBJECTIVE

The objective of this study was to evaluate the construct validity of the five-item Women's Health Initiative Insomnia Rating Scale (WHIIRS) by comparing women taking hormone therapy (HT) versus those taking a placebo and by comparing women known to differ in vasomotor symptoms.

METHODS

The WHIIRS was included in two phase III randomized trials intended to evaluate the efficacy of a combination estradiol plus and norethindrone acetate transdermal delivery system in reducing vasomotor symptoms. In all, 850 healthy postmenopausal women participated in these studies. Both trials were double-blind, one was placebo-controlled and the other was positive-controlled. The former trial admitted women with > or =8 hot flashes/day and lasted 12 weeks with data collected on the WHIIRS at baseline, 4, 8, and 12 weeks. The other trial had no entry criteria pertaining to hot flashes and lasted 52 weeks with WHIIRS data collected at baseline, 12, 24, and 52 weeks.

RESULTS

The WHIIRS was sensitive to the effect of HT on sleep disturbance over time. The WHIIRS also detected differences in self-reported sleep disturbance between women with mild vasomotor symptoms compared with those with moderate to severe symptoms. As expected, the study using a positive control revealed that sleep improved over time (p <.0001). Also as predicted, the study using a placebo control found that sleep disturbance in the treatment groups improved at a faster rate than in the control groups (p = .035).

CONCLUSION

The construct validity of the WHIIRS was supported because it was successfully used to detect self-reported sleep disturbance differences in women taking HT versus those taking a placebo as well as in groups known to differ in severity of their vasomotor symptoms.