Fiona C. Baker

A comparison of subjective estimates of sleep with objective polysomnographic data in healthy men and women

Twenty healthy men and women had their sleep recorded objectively, using polysomnography on 3 nonconsecutive nights. Following each night, the subjects assessed their sleep onset latency and number of awakenings, subjectively. Self-ratings were compared with objective measures of sleep onset latency (SOL), calculated as the time from lights-out to the first continuous minute of stage 2 sleep, and the number of awakenings which lasted 1 minute or longer on the polysomnograms. Apart from the first night, the subjects overestimated the time that it took them to fall asleep, despite sleep onset being scored as the latency to stage 2, rather than stage 1 sleep. On all 3 nights, the subjects underestimated the number of awakenings when compared to objective criteria. Although the subjects were consistent in their errors of estimation of their sleep compared to polysomnographic assessments over the three nights, the between-individual variation was large, so that objective and subjective ratings of SOL and awakenings were not correlated. The young men and women in our study, who were free of medication or sleep complaints, perceived their sleep inaccurately when compared to objective polysomnographic recordings.

Sleep and 24 hour body temperatures: a comparison in young men, naturally cycling women and women taking hormonal contraceptives

1 Body temperature has a circadian rhythm, and in women with ovulatory cycles, also a menstrual rhythm. Body temperature and sleep are believed to be closely coupled, but the influence on their relationship of gender, menstrual cycle phase and female reproductive hormones is unresolved. 2 We investigated sleep and 24 h rectal temperatures in eight women with normal menstrual cycles in their mid‐follicular and mid‐luteal phases, and in eight young women taking a steady dose of oral progestin and ethinyl oestradiol (hormonal contraceptive), and compared their sleep and body temperatures with that of eight young men, sleeping in identical conditions. All subjects maintained their habitual daytime schedules. 3 Rectal temperatures were elevated throughout 24 h in the luteal phase compared with the follicular phase in the naturally cycling women, consistent with a raised thermoregulatory set‐point. Rectal temperatures in the women taking hormonal contraceptives were similar to those of the naturally cycling women in the luteal phase. 4 Gender influenced body temperature: the naturally cycling women and the women taking hormonal contraceptives attained their nocturnal minimum body temperatures earlier than the men, and the naturally cycling women had blunted nocturnal body temperature drops compared with the men. 5 Sleep architecture was essentially unaffected by either menstrual cycle phase or gender. The women taking hormonal contraceptives had less slow wave sleep (SWS), however, than the naturally cycling women. 6 Gender, menstrual cycle phase and hormonal contraceptives significantly influenced body temperature, but had only minor consequences for sleep, in the young men and women in our study.

High nocturnal body temperatures and disturbed sleep in women with primary dysmenorrhea

Primary dysmenorrhea is characterized by painful uterine cramps, near and during menstruation, that have an impact on personal life and productivity. The effect on sleep of this recurring pain has not been established. We compared sleep, nocturnal body temperatures, and hormone profiles during the menstrual cycle of 10 young women who suffered from primary dysmenorrhea, without any menstrual-associated mood disturbances, and 8 women who had normal menstrual cycles. Dysmenorrheic pain significantly decreased subjective sleep quality, sleep efficiency, and rapid eye movement (REM) sleep but not slow wave sleep (SWS), compared with pain-free phases of the menstrual cycle and compared with the controls. Even before menstruation, in the absence of pain, the women with dysmenorrhea had different sleep patterns, nocturnal body temperatures, and hormone levels compared with the controls. In the mid-follicular, mid-luteal, and menstrual phases, the dysmenorrheics had elevated morning estrogen concentrations, higher mean in-bed temperatures, and less REM sleep compared with the controls, as well as higher luteal phase prolactin levels. Both groups of women had less REM sleep when their body temperatures were high during the luteal and menstrual phases, implying that REM sleep is sensitive to elevated body temperatures. We have shown that dysmenorrhea is not only a disorder of menstruation but is manifest throughout the menstrual cycle. Furthermore, dysmenorrheic pain disturbs sleep, which may exacerbate the effect of the pain on daytime functioning.

Self-reported sleep across the menstrual cycle in young, healthy women

OBJECTIVE To establish the association between subjective sleep and phase of the menstrual cycle in healthy, young, ovulating women. METHODS Twenty-six women (mean age: 21 years) who did not suffer from any menstrual-associated disorders, and in whom we had detected ovulation, completed daily questionnaires about their sleep over 1 month. RESULTS The women reported a lower sleep quality over the 3 premenstrual days and 4 days during menstruation, compared to the mid-follicular and early/mid luteal phases. Total sleep time, sleep onset latency, number and duration of awakenings, and morning vigilance were not affected by the menstrual cycle. CONCLUSION The normal, ovulatory cycle is associated with changes in the perception of sleep quality but not sleep continuity in healthy, young women. The temporal relationship of sleep complaints with menstrual phase should be considered in the evaluation of sleep disorders, particularly insomnia, in women.

Menstrual factors in sleep

The changing endocrine profile in premenopausal women alters aspects of sleep and circadian rhythms. Subjectively women appear to feel a greater need for sleep and report poor and insufficient sleep more often than men. This greater sleep requirement may manifest with a higher amplitude of slow-wave sleep in the EEG in women. Healthy young women, with biphasic body temperature rhythms of ovulatory menstrual cycles, have more stage 2 sleep, higher spindle frequency activity and less rapid-eye movement (REM) sleep when progesterone predominates in the luteal phase. These sleep-EEG changes may largely be caused by neurosteroids acting on the brain. Sleep regulatory mechanisms, indicated by the onset to sleep, slow-wave sleep (SWS) and slow-wave activity, appear to be unaffected by menstrual phase in women with normal cycles. Women with premenstrual mood symptoms have more stage 2 sleep and seemingly less SWS and REM sleep, a blunted circadian rhythm of melatonin and an earlier minimum body temperature than asymptomatic women. Subjective repercussions include increased daytime sleepiness, lethargy and fatigue. Treatment strategies for menstrual-associated complaints include using oral contraceptives and sleep deprivation but the physiology and pharmacology of normal menstrual changes, the disorders and their treatment need to be better understood.

Association of sociodemographic, lifestyle, and health factors with sleep quality and daytime sleepiness in women: findings from the 2007 National Sleep Foundation "Sleep in America Poll".

OBJECTIVES To investigate factors associated with poor sleep quality and daytime sleepiness in women living in the United States. METHODS Data are presented from the National Sleep Foundations 2007 Sleep in America Poll that included 959 women (18-64 years of age) surveyed by telephone about their sleep quality, daytime sleepiness, and sociodemographic, health, and lifestyle factors. RESULTS Poor sleep quality was reported by 27% and daytime sleepiness was reported by 21% of respondents. Logistic multivariate regression analyses revealed that poor sleep quality and daytime sleepiness were both independently associated with poor health, having a sleep disorder, and psychological distress. Also, multivariate analyses showed that women who consumed more caffeinated beverages and those who had more than one job were more likely to report poor sleep quality but not daytime sleepiness. Daytime sleepiness, on the other hand, was independently associated with being black/African American, younger, disabled, having less education, and daytime napping. CONCLUSIONS Poor sleep quality and daytime sleepiness are common in American women and are associated with health-related, as well as sociodemographic, factors. Addressing sleep-related complaints in women is important to improve their daytime functioning and quality of life.

Perceived poor sleep quality in the absence of polysomnographic sleep disturbance in women with severe premenstrual syndrome

Women with severe premenstrual syndrome report sleep‐related complaints in the late‐luteal phase, but few studies have characterized sleep disturbances prospectively. This study evaluated sleep quality subjectively and objectively using polysomnographic and quantitative electroencephalographic measures in women with severe premenstrual syndrome. Eighteen women with severe premenstrual syndrome (30.5 ± 7.6 years) and 18 women with minimal symptoms (controls, 29.2 ± 7.3 years) had polysomnographic recordings on one night in each of the follicular and late‐luteal phases of the menstrual cycle. Women with premenstrual syndrome reported poorer subjective sleep quality when symptomatic in the late‐luteal phase compared with the follicular phase (P < 0.05). However, there were no corresponding changes in objective sleep quality. Women with premenstrual syndrome had more slow‐wave sleep and slow‐wave activity than controls at both menstrual phases (P < 0.05). They also had higher trait‐anxiety, depression, fatigue and perceived stress levels than controls at both phases (P < 0.05) and mood worsened in the late‐luteal phase. Both groups showed similar menstrual‐phase effects on sleep, with increased spindle frequency activity and shorter rapid eye movement sleep episodes in the late‐luteal phase. In women with premenstrual syndrome, a poorer subjective sleep quality correlated with higher anxiety (r = −0.64, P = 0.005) and more perceived nighttime awakenings (r = −0.50, P = 0.03). Our findings show that women with premenstrual syndrome perceive their sleep quality to be poorer in the absence of polysomnographically defined poor sleep. Anxiety has a strong impact on sleep quality ratings, suggesting that better control of mood symptoms in women with severe premenstrual syndrome may lead to better subjective sleep quality.

Sleep evoked delta frequency responses show a linear decline in amplitude across the adult lifespan

Aging is associated with many changes in sleep, with one of the most prominent being a reduction in slow wave sleep. Traditional measures of this phenomenon rely on spontaneous activity and typically confound the incidence and amplitude of delta waves. The measurement of evoked K-complexes during sleep, enable separate assessment of incidence and amplitude taken from the averaged K-complex waveform. The present study describes data from 70 normal healthy men and women aged between 19 and 78 years. K-Complexes were evoked using short auditory tones and recorded from a midline array of scalp sites. Significant reductions with age were seen in the amplitude of the N550 component of the averaged waveform, which represents the amplitude of the K-complex, with linear regression analysis indicating approximately 50% of the variance was due to age. Smaller, yet still significant reductions were seen in the ability to elicit K-complexes. The data highlight the utility of evoked K-complexes as a sensitive marker of brain aging in men and women.

Reduced parasympathetic activity during sleep in the symptomatic phase of severe premenstrual syndrome

OBJECTIVE Severe premenstrual syndrome (PMS) is a common distressing disorder in women that manifests during the premenstrual (late-luteal) phase of the ovulatory menstrual cycle. There is some evidence that altered autonomic function may be an important component of PMS, but few studies have used heart rate variability (HRV) as a sensitive marker of autonomic activity in severe PMS, and findings are conflicting. METHODS We investigated HRV during sleep, a state that is relatively free of external disruptions, in 9 women with severe PMS and 12 controls. RESULTS The normal-to-normal (NN) RR interval was shorter during the sleep period in women with PMS than in controls in both the follicular and the late-luteal phases of the menstrual cycle. The standard deviation of all NN intervals, a measure of total variability in the interbeat interval, was lower during the sleep period in the late-luteal phase than in the follicular phase in women with PMS. The square root of the mean of the sum of the squares of differences between adjacent NN intervals, a measure reflecting high-frequency (HF) activity, showed a similar pattern. HF power, a marker of parasympathetic activity, was lower during non-rapid eye movement (non-REM) and REM sleep in the late-luteal phase than in the follicular phase in women with severe PMS. Controls had a shorter NN interval, but similar HRV measures, in the late-luteal phase compared with the follicular phase. CONCLUSION These results suggest that women with severe PMS have decreased parasympathetic activity during sleep in association with their premenstrual symptoms in the late-luteal phase compared with the follicular phase when they are symptom-free.

Reduced quality of life when experiencing menstrual pain in women with primary dysmenorrhea

Primary dysmenorrhea is the most common gynecological condition among women of reproductive age. Although dysmenorrhea has been reported to affect the ability of women to carry out daily activities, the impact of primary dysmenorrheic pain specifically on quality of life (QoL), has yet to be elucidated. We investigated whether QoL varies between women with and without severe primary dysmenorrhea, and whether QoL is impaired only during menstruation or also during pain‐free phases of the menstrual cycle. Twelve women with severe primary dysmenorrhea and nine control women completed the quality of life enjoyment and satisfaction questionnaire (Q‐LES‐Q‐SF) during menstruation and during the late follicular phase. Women with dysmenorrhea had a significant reduction in Q‐LES‐Q‐SF scores (mean ± SD: 54 ± 18%, percentage of the total maximum possible score) when they were experiencing severe menstrual pain compared with their own pain‐free follicular phase (80 ± 14%, p < 0.0001) and compared with controls during menstruation (81 ± 10%, p < 0.0001). They also rated their overall life satisfaction and contentment as poorer during menstruation. Severe menstrual pain associated with primary dysmenorrhea, therefore, impacts health‐related of QoL.