Insomnia related to postmenopausal syndrome and hormone replacement therapy: sleep laboratory studies on baseline differences between patients and controls and double-blind, placebo-controlled investigations on the effects of a novel estrogen-progestogen combination (Climodien, Lafamme) versus estrogen alone

Effect of external sleep disturbance on sleep architecture in perimenopausal and postmenopausal women

OBJECTIVE

This study aimed to use external sleep disturbance as a model to evaluate sleep architecture in climacteric women before and after menopausal hormone therapy (MHT).

METHODS

Seventeen perimenopausal and 18 postmenopausal women underwent a polysomnography protocol: an adaptation night, a reference night and a sleep disturbance night with one hand loosely tied to the bed for blood sampling. The sleep architecture of the reference and disturbance nights were compared. The 24-h urinary free cortisol concentration (UFC) was measured. The procedure was repeated after 6 months on MHT or placebo.

RESULTS

Fifteen perimenopausal and 17 postmenopausal women completed the study. The perimenopausal and postmenopausal groups were combined. During external sleep disturbance, sleep was shorter and more fragmented; with less stage 2, slow-wave and rapid eye movement (REM) sleep and more wake time and awakenings, both at baseline and after the treatment period. Compared to the placebo group, sleep disturbance was minor for women on MHT: sleep was not shortened and the amount of slow-wave sleep did not decrease. Increased 24-h UFC was observed only during MHT.

CONCLUSIONS

Sleep in climacteric women is easily disturbed, leading to shorter and more fragmented sleep with less deep sleep and REM sleep. Six months of MHT attenuates the observed sleep disturbance.

Trajectory of Perinatal Depressive Symptoms from the Second Trimester to Three Months Postpartum and Its Association with Sleep Quality

Purpose

Few studies have explored the association between sleep quality and depressive symptoms in perinatal women from the second trimester to the postpartum period. This study aims to explore this relationship using a longitudinal design.

Patients and Methods

Participants were enrolled at 15 gestational weeks. Demographic information was collected. Perinatal depressive symptoms were measured using the Edinburgh Postnatal Depression Scale (EPDS). Sleep quality was measured employing the Pittsburgh Sleep Quality Index (PSQI) at five timepoints from enrollment to three months postpartum. Overall, 1416 women completed the questionnaires at least thrice. A Latent Growth Curve (LGC) model was performed to identify the relationship between the trajectories of perinatal depressive symptoms and sleep quality.

Results

Of the participants, 23.7% screened positive at least once on the EPDS. The perinatal depressive symptoms trajectory, fitted by the LGC model, decreased at early pregnancy and increased from 15 gestational weeks to three months postpartum. The intercept of sleep trajectory positively affected the intercept of perinatal depressive symptoms' trajectory; the slope of sleep trajectory positively affected both the slope and the quadratic coefficient of perinatal depressive symptoms' trajectory.

Conclusion

The trajectory of perinatal depressive symptoms increased from 15 gestational weeks to three months postpartum following a quadratic trend. Poor sleep quality was associated with depression symptoms beginning at the onset of pregnancy. Moreover, rapidly declining sleep quality could be a significant risk factor for perinatal depression (PND). These findings call for greater attention to perinatal women who report poor and persistently deteriorating sleep quality. Additional sleep-quality evaluations, depression assessments, and referrals to mental health care providers may benefit these women and support PND prevention, screening, and early diagnosis.

The role of ovarian hormones in the pathophysiology of perimenopausal sleep disturbances: A systematic review

Sleep disturbance is a common clinical concern throughout the menopausal transition. However, the pathophysiology and causes of these sleep disturbances remain poorly understood, making it challenging to provide appropriate therapy. Our goal was to i) review the literature about the influence of ovarian hormones on sleep in perimenopausal women, ii) summarize the potential underlying pathophysiology of menopausal sleep disturbances and iii) evaluate the implications of these findings for the therapeutic approach to sleep disturbances in the context of menopause. A systematic literature search using the databases Embase, MEDLINE and Cochrane Library was conducted. Keywords relating to ovarian hormones, sleep disturbances and menopause were used. Ultimately, 86 studies were included. Study Quality Assessment Tools of the National Institutes of Health were used for quality assessment. Results from good-quality studies demonstrated that the postmenopausal decline in estrogen and progesterone contributes to sleep disturbances in women and that timely treatment with estrogen and/or progesterone therapy improved overall sleep quality. Direct and indirect effects of both hormones acting in the central nervous system and periphery, as well as via secondary effects (e.g. reduction in vasomotor symptoms), can contribute to improvements in sleep. To strengthen external validity, studies examining neurobiological pathways are needed.

Association of hormone therapy and changes of objective sleep quality in women of late menopausal transition with sleep disorder: a preliminary study

OBJECTIVE

The aim of this study was to investigate changes in objective sleep quality with hormone therapy (HT) in women with late menopausal transition.

METHODS

Healthy midlife women with sleep difficulty who received HT were included. Those undergoing late menopausal transition were screened. Sleep patterns and self-reported questionnaires were collected before and 10 weeks after starting HT.

RESULTS

Ten women who met the criteria (age, 50.1 ± 2.8 years) showed higher sleep efficiency and shorter wakefulness after sleep onset (WASO) 10 weeks after starting HT. However, no significant change was found in objective sleep quality after adjustment for multiple comparisons: sleep efficiency, 84.2 ± 7.7 versus 88.2% ± 4.7%, P = 0.037, adjusted P = 0.259; WASO, 59.0 ± 27.2 minutes versus 41.4 ± 17.4 minutes, P = 0.020, adjusted P = 0.140; average duration per awakening, 2.9 ± 1.0 minutes versus 2.2 ± 0.5 minutes, P = 0.033, adjusted P = 0.231. A better score of subjective sleep quality in the Pittsburgh Sleep Quality Index was observed 10 weeks after starting HT (2.0 ± 0.0 vs 1.2 ± 0.4, P = 0.006, adjusted P = 0.042), but sensitivity analysis did not show consistent results after adjustment for multiple comparisons (2.0 ± 0.0 vs 1.1 ± 0.4, P = 0.020, adjusted P = 0.140). Total scores of the Insomnia Severity Index and Menopause Rating Scale were better 10 weeks after starting HT (Insomnia Severity Index, 14.7 ± 3.0 vs 9.1 ± 3.8, P = 0.010; Menopause Rating Scale, 29.0 ± 5.2 vs 21.6 ± 3.0, P = 0.009) with consistent results in sensitivity analyses. There was no difference in the Epworth Sleepiness Scale before and after HT (7.2 ± 1.7 vs 8.6 ± 4.5, P = 0.309). The change in each objective sleep quality variable before and after HT showed strong positive or negative correlations with the change in only a few items in subjective sleep quality.

CONCLUSION

Women in the late menopausal transition period showed higher sleep efficiency and shorter WASO after HT; however, multiple comparisons showed no statistically significant difference in objective sleep quality between before and after HT.

Different regimens of menopausal hormone therapy for improving sleep quality: a systematic review and meta-analysis

IMPORTANCE

Long-term sleep disturbances in menopausal women are closely related to cardiovascular disorders, metabolic disorders, and cognitive impairment. At present, hormone therapy (HT) is a standard treatment for menopausal symptoms. However, it remains unclear whether HT can improve sleep quality.

OBJECTIVE

We did a systematic review and meta-analysis to assess the effects of different HT regimens on menopausal sleep quality.

EVIDENCE REVIEW

We systematically searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, PsycINFO, CINAHL, and Web of Science for randomized controlled trials of menopausal HT on sleep disturbances up to June 14,2021. Information about ongoing and unpublished trials was collected by searching WHOICTRP and ClinicalTrials.gov. Our primary outcome was sleep quality with objective measurements. We estimated the standardized mean difference (SMD) using random-effects models.

FINDINGS

We identified a total of 3,059 studies and finally included 15 studies in the meta-analysis. Compared with placebo, HT improved self-reported sleep outcomes (SMD = -0.13; 95% CI, -0.18 to -0.08, P  < 0.00001 and I2 = 41%), but not sleep parameters measured by polysomnography. Subgroup analyses according to the regimen of HT showed that 17β-estradiol (17β-E2) (SMD = -0.34; 95% CI, -0.51 to -0.17, P  < 0.0001, and I2 = 0%) and conjugated equine estrogens (SMD = -0.10; 95% CI, -0.12 to -0.07, P  < 0.00001, and I2 = 0%) improved sleep quality. Moreover, transdermal administration (SMD = -0.35; 95% CI, -0.64 to -0.06, and P  = 0.02) was more beneficial than oral (SMD = -0.10; 95% CI, -0.14 to -0.07, and P  < 0.00001). In addition, the combination of estrogen and progesterone had a positive effect on sleep disturbance (SMD = -0.10; 95% CI, -0.13 to -0.07, P  < 0.00001, and I2 = 0%), while estrogen monotherapy did not. The results showed that estrogen/micronized progesterone (SMD = -0.22; 95% CI, -0.37 to -0.06, P = 0.007, and I2 = 0%) and estrogen/medroxyprogesterone acetate (SMD = -0.10; 95% CI, -0.13 to -0.07, P  < 0.00001, and I2 = 0%) could alleviate sleep disturbance.

CONCLUSIONS AND RELEVANCE

HT has a beneficial effect on sleep disturbance to some extent, and the formulations and routes of administration of hormonal agents influence the effect size.

Pharmacologic and hormonal treatments for menopausal sleep disturbances: A network meta-analysis of 43 randomized controlled trials and 32,271 menopausal women

This network meta-analysis aimed at investigating efficacy/tolerability of pharmacologic/hormonal interventions for menopausal sleep disturbances. Major databases were searched for randomized controlled trials (RCTs) examining pharmacologic or hormonal interventions with either placebo or active controlled designs. Primary outcomes were improvements in sleep disturbance severity/tolerability (i.e., overall dropout rates), whereas secondary outcome was adverse event-related discontinuation rates. Analysis of 43 RCTs with 25 treatment arms involving 32,271 women during/after menopausal transition (age: 61.24 ± 4.23, duration: 90.83 ± 66.29 wks) showed therapeutic effect of melatonin-fluoxetine [SMD = -2.47 (95% CI:-4.19-0.74)] against sleep disturbances compared to placebo. Subgroup analysis of 15 RCTs on vasomotor symptoms demonstrated superior benefits of gabapentin [SMD = -1.04 (95% CI:-1.90-0.18)], oral combined hormone therapy [SMD = -0.62 (95% CI:-1.06-0.18)], and bazedoxifene-conjugated estrogens [SMD = -0.50 (95% CI:-0.96-0.04)] to placebo/control. Despite benefits of raloxifene-only [SMD = -1.86 (95% CI:-3.09-0.63)] and raloxifene-oral estrogen [SMD = -2.64 (95% CI:-4.64-0.63)], patient selection may be a confounder. Dropout rates were comparable between interventions and placebo/control. Eszopiclone [RR = 3.84 (95% CI: 1.14-12.87)] and oral combined hormone therapy [RR = 2.51 (95% CI: 1.04-6.07)] were associated with higher rates of adverse event-related discontinuation. The results support combined estrogen-progesterone therapy for menopausal sleep disturbances associated with vasomotor symptoms but showed no significant effects of hypnotics in this clinical setting.

Insomnia and menopause: a narrative review on mechanisms and treatments

The menopausal transition is associated with an increased frequency of sleep disturbances. Insomnia represents one of the most reported symptoms by menopausal women. According to its pathogenetic model (3-P Model), different predisposing factors (i.e. a persistent condition of past insomnia and aging per se) increase the risk of insomnia during menopause. Moreover, multiple precipitating and perpetuating factors should favor its occurrence across menopause, including hormonal changes, menopausal transition stage symptoms (i.e. hot flashes, night sweats), mood disorders, poor health and pain, other sleep disorders and circadian modifications. Thus, insomnia management implies a careful evaluation of the psychological and somatic symptoms of the individual menopausal woman by a multidisciplinary team. Therapeutic strategies encompass different drugs but also behavioral interventions. Indeed, cognitive behavioral therapy represents the first-line treatment of insomnia in the general population, regardless of the presence of mood disorders and/or vasomotor symptoms (VMS). Different antidepressants seem to improve sleep disturbances. However, when VMS are present, menopausal hormone therapy should be considered in the treatment of related insomnia taking into account the risk-benefit profile. Finally, given its good tolerability, safety, and efficacy on multiple sleep and daytime parameters, prolonged-released melatonin should represent a first-line drug in women aged ≥ 55 years.

Role of menopause and hormone replacement therapy in sleep-disordered breathing

There are suggestions that the loss of female sex hormones following menopause is critical for the development or progression of sleep-disordered breathing (SDB). We conducted a review of the literature on the role of menopause and hormone replacement therapy (HRT) in SDB risk. There is an increase in SDB during the menopausal transition period, but data on an effect beyond that of increasing age and changes in body habitus are weak or absent. Early community-based, observational studies reported a protective effect by HRT on SDB prevalence, but this could possibly be explained as a healthy user effect. Interventional studies of the effect of HRT on SDB are sparse, with only a few randomized placebo-controlled studies, often performed on small samples of women without clinically significant SDB. HRT regimens have varied and all the studies are fairly old. They do not definitely assure the alleviation of SDB and HRT cannot thus be recommended as treatment for SDB. It is concluded that there is no evidence that female sex hormone changes during menopause per se are able to explain the increase in SDB in midlife women and conclusions on the effect of HRT on SDB cannot be drawn from the current literature.

Link between insomnia and perinatal depressive symptoms: A meta-analysis

Evidence shows the possible link between insomnia and perinatal depressive symptoms. In order to find a convergent quantitative answer, we collected data via the search of Medline, EMBASE and reference tracking, which included nine studies (a total sample of 1,922 women). An aggregate effect size estimate (correlation coefficient) was generated using the comprehensive meta-analysis software. For the meta-analytic procedure, a random effects model was set a priori. Moderating factors, including study design, method of assessment of depression, geographical origin of data, publication year, mean age, % married, breastfeeding rate, quality and type of data, % primiparous and history of depression, were examined via categorical or univariate mixed-effects (method of moments) meta-regression methods. Heterogeneity and publication bias were examined using standard meta-analytic approaches. We found a significant, medium-size relationship between insomnia and perinatal depressive symptoms (point estimate, 0.366; 95% confidence interval [CI], 0.205-0.508; p < 0.001; n = 9) and this was significantly heterogeneous (Q, 118.77; df, 8; p < 0.001; I² , 93.26%). The effect size estimate was significant for studies reporting no history of depression (point estimate, 0.364; 95% CI, 0.035-0.622; p < 0.05; n = 5) and for study design. With meta-regression, no moderating factor (age, marriage rate, breastfeeding rate, pregnancy history or publication year) significantly mediated the effect size estimate. The depression assessment scale used, but not other categorical variables, explained the magnitude of heterogeneity. We found that insomnia during the perinatal period is associated with depressive symptoms, which warrants screening pregnant mothers for insomnia and depression.

Efficacy of menopausal hormone therapy on sleep quality: systematic review and meta-analysis

Sleep complaints are reported by 40-60 % of menopausal women. Poor sleep is a risk factor for cardiovascular disease, diabetes, and obesity. The effect of menopausal hormone therapy on sleep quality is unclear. A systematic review and meta-analysis were conducted to summarize the efficacy of menopausal hormone therapy on self-reported sleep quality. Electronic databases (PubMed, Scopus, Ovid MEDLINE, EMBASE, EBM Reviews CENTRAL, and PsycInfo) were searched from 2002 to October 2015. Randomized trials assessing the effect of menopausal hormone therapy with a minimum follow up of 8 weeks were included. Titles, abstracts, and full texts were screened independently and in duplicate. Primary outcome included sleep items within a questionnaire, scale or diary. Standardized mean differences across trials were pooled using random-effects models. The search identified 424 articles, from which 42 trials were included. Seven trials at a moderate to high risk of bias enrolling 15,468 women were pooled in meta-analysis. Menopausal hormone therapy improved sleep quality in women who had vasomotor symptoms at baseline [standardized mean difference -0.54 (-0.91 to -0.18), moderate quality evidence]. No difference was noted when women without such symptoms were analyzed separately or combined. Across 31 sleep quality questionnaires, daytime dysfunction was the most evaluated sleep domain. Menopausal hormone therapy improves sleep in women with concomitant vasomotor symptoms. Heterogeneity of trials regarding study population, formulations, and sleep scales; limit overall certainty in the evidence. Future menopausal hormone therapy trials should include assessment of self-reported sleep quality using standardized scales and adhere to reporting guidelines.

Treatment of chronic insomnia disorder in menopause: evaluation of literature

OBJECTIVE

Insomnia both as a symptom and as part of chronic insomnia disorder is quite common in menopause. Comorbid conditions, such as restless legs syndrome and obstructive sleep apnea, occur with high prevalence among perimenopausal women with insomnia. Insomnia in this population group is associated with adverse health outcomes, and there are no clear standards on how to treat it.

METHODS

Based on extensive literature search, 76 articles were identified. Two authors independently graded evidence according to the Oxford Centre for Evidence-Based Medicine Levels of Evidence.

RESULTS

Evaluation and treatment of other comorbid sleep disorders are recommended, as is cognitive-behavioral therapy for insomnia. Hormone therapy, eszopiclone, escitalopram, gabapentin, isoflavones, valerian, exercise, and hypnosis are suggested. Zolpidem, quiteiapine XL, citalopram, mirtazapine followed by long-acting melatonin, ramelteon, Pycnogenol, Phyto-Female Complex, yoga, and massage may be considered. Kampo formulas are not recommended. Acupuncture may not be suggested, and cognitive-behavioral therapy that is not tailored for insomnia probably should not be considered.

CONCLUSIONS

Although a variety of interventions are shown to be helpful in improving sleep in menopause, there is a need for well-designed head-to-head trials with uniform outcome measures.

Menopausal hormone therapy and sleep-disordered breathing: evidence for a healthy user bias

PURPOSE

Observational studies suggest that menopausal hormone therapy protects against sleep-disordered breathing, but such findings may be biased by a "healthy user effect." When the Women's Health Initiative Study reported in 2002 that estrogen-progestin therapy increases heart disease risk, many women discontinued hormone therapy. We investigate healthy user bias in the association of hormone therapy with sleep-disordered breathing in the Sleep in Midlife Women Study.

METHODS

A total of 228 women aged 38 to 62 years were recruited from the Wisconsin Sleep Cohort Study. They underwent polysomnography to measure apnea-hypopnea index, at home semiannually from 1997 to 2006, and in the sleep laboratory every four years (n = 1828 studies). Hormone therapy was recorded monthly. Linear models with empirical standard errors regressed logarithm of apnea-hypopnea index on hormone use with a pre- or post-July 2002 interaction, adjusting for menopause and age.

RESULTS

The association of hormone therapy and sleep-disordered breathing was heterogeneous (P < .01); apnea-hypopnea index among users was 15% lower in the early period (95% confidence interval, -27% to -1%), but similar to nonusers in the late.

CONCLUSIONS

Hormone therapy was negatively associated with sleep-disordered breathing only until the Women's Health Initiative results were publicized. Hormone therapy may have been a marker for healthfulness in the early period, creating a spurious association with sleep-disordered breathing.

Pharmacological treatment of sleep disorders and its relationship with neuroplasticity

Sleep and wakefulness are regulated by complex brain circuits located in the brain stem, thalamus, subthalamus, hypothalamus, basal forebrain, and cerebral cortex. Wakefulness and NREM and REM sleep are modulated by the interactions between neurotransmitters that promote arousal and neurotransmitters that promote sleep. Various lines of evidence suggest that sleep disorders may negatively affect neuronal plasticity and cognitive function. Pharmacological treatments may alleviate these effects but may also have adverse side effects by themselves. This chapter discusses the relationship between sleep disorders, pharmacological treatments, and brain plasticity, including the treatment of insomnia, hypersomnias such as narcolepsy, restless legs syndrome (RLS), obstructive sleep apnea (OSA), and parasomnias.

Association between sleep and breast cancer incidence among postmenopausal women in the Women's Health Initiative

STUDY OBJECTIVES

To determine whether the duration of sleep, sleep quality, insomnia, or sleep disturbance was associated with incident breast cancer in the Women's Health Initiative (WHI).

DESIGN

Prospective cohort study.

SETTING

Women enrolled in one of the Clinical Trial (CT) arms or the Observational Study (OS) from the WHI conducted in the United States.

PARTICIPANTS

This study included 110,011 women age 50 to 79 years with no history of cancer.

MEASUREMENTS AND RESULTS

Typical sleep duration, sleep quality, and other self-reported sleep measures over the past 4 weeks were assessed during the screening visits for both the CT and OS participants. The presence of insomnia and level of sleep disturbance was calculated from an index of the WHI Insomnia Rating Scale. The outcome for this study was primary, invasive breast cancer. A total of 5,149 incident cases of breast cancer were identified in this study. No statistically significant associations were found between sleep duration, sleep quality, insomnia, or level of sleep disturbance with the risk of breast cancer after multivariable adjustment. A positive trend was observed for increasing sleeping duration with the risk of estrogen receptor positive breast cancer, but the association estimates for each sleep duration category were weak and nonsignificant.

CONCLUSIONS

This study does not provide strong support for an association between self-reported sleep duration, sleep quality, insomnia, or sleep disturbance with the risk of breast cancer.

Insomnia symptoms and cardiorespiratory fitness in healthy individuals: the Nord-Trøndelag Health Study (HUNT)

STUDY OBJECTIVES

Previous studies have found an inverse association between insomnia and self-reported physical activity, but it is not clear whether insomnia is associated with cardiorespiratory fitness. Our aim was to investigate different insomnia symptoms in relation to the gold standard measure of cardiorespiratory fitness, i.e., peak oxygen uptake (VO(2peak)).

DESIGN

Cross-sectional population study.

SETTING

Nord-Trøndelag County, Norway.

PARTICIPANTS

The group comprised 3,489 men and women who were free from cardiovascular or pulmonary diseases, cancer, and sarcoidosis and who did not use antihypertensive medication. They were included in the fully adjusted model when assessing all insomnia symptoms simultaneously.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

For insomnia, the participants reported how often they had experienced sleep problems during the past 3 months, including difficulties falling asleep at night, repeated awakenings during the night, early awakenings without being able to go back to sleep, and daytime sleepiness. Response options were "never/almost never," "sometimes" or "several times a wk." To measure cardiorespiratory fitness, the participants were asked to walk or run on a treadmill with increasing speed and/or incline until exhaustion, and VO(2peak) was recorded. We found a modest inverse and graded association of the insomnia symptoms with VO(2peak). The association was independent of self-reported physical activity and was apparent for all insomnia symptoms except for early awakenings. We found a dose-response relation for a cumulative combination of insomnia symptoms and VO(2peak) for experiencing zero, one to two, or three to four symptoms (P for trend < 0.001).

CONCLUSIONS

We found a modest inverse association of insomnia with VO(2peak) independent of the conventional cardiovascular risk factors and self-reported physical activity.

The Effects of a Gentle Yoga Program on Sleep, Mood, and Blood Pressure in Older Women with Restless Legs Syndrome (RLS): A Preliminary Randomized Controlled Trial

Objective. To examine the effects of yoga versus an educational film program on sleep, mood, perceived stress, and sympathetic activation in older women with RLS. Methods. Participants were drawn from a larger trial regarding the effects of yoga on cardiovascular disease risk profiles in overweight, sedentary postmenopausal women. Seventy-five women were randomized to receive either an 8-week yoga (n = 38) or educational film (n = 37) program. All 75 participants completed an RLS screening questionnaire. The 20 women who met all four diagnostic criteria for RLS (n = 10 yoga, 10 film group) comprised the population for this nested study. Main outcomes assessed pre- and post-treatment included: sleep (Pittsburgh Sleep Quality Index), stress (Perceived Stress Scale), mood (Profile of Mood States, State-Trait Anxiety Inventory), blood pressure, and heart rate. Results. The yoga group demonstrated significantly greater improvements than controls in multiple domains of sleep quality and mood, and significantly greater reductions in insomnia prevalence, anxiety, perceived stress, and blood pressure (all P's≤0.05). Adjusted intergroup effect sizes for psychosocial variables were large, ranging from 1.9 for state anxiety to 2.6 for sleep quality. Conclusions. These preliminary findings suggest yoga may offer an effective intervention for improving sleep, mood, perceived stress, and blood pressure in older women with RLS.

Primary menopausal insomnia: definition, review, and practical approach

OBJECTIVE

To present a case of primary menopausal insomnia with hot flashes to introduce recent changes in technology and nomenclature of sleep medicine and to review presentation, diagnosis, and therapies for menopausal insomnia.

METHODS

Clinical findings and results of sleep evaluation in the menopausal study patient are presented with details about polysomnography performed before and after therapy with pregabalin.

RESULTS

A 56.5-year-old female athlete with severe hot flashes and insomnia of 12 years' duration was treated with pregabalin, which ameliorated the hot flashes and sweats and improved sleep quality and architecture. Menopause is associated with hormonal and metabolic changes that disrupt sleep. Disruption of sleep can in turn lead to morbidity and metabolic sequelae. Hormonal treatment, although effective, carries risks unacceptable to many patients and physicians. To date, nonhormonal therapies of symptomatic menopause have not been objectively studied for effects on sleep efficiency and architecture. Primary menopausal insomnia is insomnia associated with menopause and not attributable to secondary causes. Polysomnographically, it seems characterized by a high percentage of slow-wave (N3) sleep, decreased rapid eye movement sleep, cyclic alternating pattern, and arousals.

CONCLUSIONS

Primary menopausal insomnia is probably mediated through a mechanism separate from hot flashes, and one can occur without the other. Thermal dys-regulation and sleep abnormalities of menopause are probably related to more general changes mediated through loss of estrogenic effects on neuronal modulation of energy metabolism, and more clinical direction is expected as this research field develops. Identification of sleep disorders in menopausal women is important, and polysomnographic evaluation is underused in both clinical and research evaluations of metabolic disturbances.

Changes in the sleep electroencephalogram (EEG) during male to female transgender therapy

Steroids, including estrogens, participate in sleep regulation. For example estrogen replacement therapy improved sleep quality in postmenopausal women. Patients, who undergo a cross-gender hormone therapy, receive high doses of estrogens. The effects of this treatment on sleep are unknown. To clarify this issue, we examined seven male to female transsexual patients (age range 31-44 years, mean±SD 35.9±4.2 years). The patients spent two nights on 2 separate occasions in our sleep laboratory. The first night of each session served for adaptation to laboratory conditions. In the second night sleep electroencephalogram [EEG] was recorded from 2300h to 0700h. The first examination was performed before and the second about 3 months after initiation of cross-gender hormone therapy with a dose of 80-100mg estrogen applied every 2 weeks. Additionally patients were treated with a starting dose of the anti-androgen cyproteronacetate of 100mg/day and after about 6 weeks with a maintenance therapy of 50mg/d in order to suppress androgenic effects. Statistical analysis was performed with the Wilcoxon rank test. Under this estrogen therapy we found a significant increase in stage 1 sleep during the whole night (at baseline [b]: 33.29±9.94min; treatment [t]: 51.57±24.26min; p<0.05) Beta activity in nonREM sleep was significantly increased (p=0.02) during hormone therapy compared to before treatment. Other sleep EEG parameters showed no significant changes. Administration of estrogen and anti-androgens in male to female transsexual patients had only a small influence on sleep EEG, with an increase in the duration of shallow sleep.

Biological Consequences of Disturbed Sleep: Important Mediators of Health?

There is an extensive literature regarding the immunological and endocrinological consequences of illness, stress, and psychopathology. Yet only a modest literature is available regarding the potential unfavorable effects of chronic sleep loss/disruption on immune and endocrine pathways or on various aspects of health. Given that humans spend approximately 1/3 of their lives asleep, it seems pertinent to evaluate this necessary yet understudied behavior. The evidence overwhelmingly indicates that "excessive" sleep disruption or poor sleep quality/continuity may subsequently increase risk for adverse health outcomes, as well as mortality. This is thought to occur through dysregulation of biological pathways. While our information addressing the immunological or endocrinological consequences of poor sleep is mounting, the majority of evidence stems from epidemiologic and cross-sectional studies. The immune and endocrine systems are dynamic and constantly in flux. Thus, the methodologies and study designs used to understand how sleep affects these systems needs to be as dynamic. Experimental manipulations and longitudinal evaluations are needed to effectively understand sleep as a risk factor for health. Thus, this paper is a primer in which to highlight the immunological and endocrinological consequences of disrupted or disturbed sleep as well as describe how these relationships may impact overall health. It is also meant to spark an interest for future evaluations of how the behavior of sleep is relevant to health.

Evaluation and management of sleep disturbance during the menopause transition

Sleep disturbances in midlife women are common and have been associated with the menopause transition itself, symptoms of hot flashes, anxiety and depressive disorders, aging, primary sleep disorders (i.e., obstructive sleep apnea, periodic limb movement disorder), comorbid medical conditions and medications, as well as with psychosocial and behavioral factors. Because there are several common sources of sleep problems in midlife women, the cause of an individual woman's sleep disturbance may be multifactorial. Effective behavioral and pharmacological therapies are available to treat sleep disturbances of different etiologies. This review provides an overview of different types of sleep disturbance occurring in midlife women and presents data supporting the use of hormone therapy, hypnotic agents, and behavioral strategies to treat sleep problems in this population. The review aims to equip clinicians evaluating menopause-age women with the knowledge and evaluation tools to diagnose, engage sleep experts where appropriate, and treat sleep disturbance in this population. Sleep disorders in midlife women should be treated because substantial improvements in quality of life and health outcomes are achievable.

Can improving sleep influence sleep-disordered breathing?

Sleep-disordered breathing (SDB) encompasses a group of disorders that include obstructive sleep apnoea (OSA), central sleep apnoea (CSA) and nocturnal hypoventilation. SDB commonly coexists with sleep disorders such as insomnia and restless legs syndrome, and sleep deprivation has been shown to play a role in the pathogenesis of SDB. Participants of a workshop, held at the 6th annual meeting of The International Sleep Disorders Forum: The Art of Good Sleep in 2008, evaluated whether the effective management of sleep disorders could result in a reduction in SDB. Following the workshop, a critical review of the literature in the field of sleep and SDB was conducted in order to assess the impact of improving sleep on SDB, and to determine whether measures taken to improve sleep result in a subsequent improvement in SDB. Results showed that studies evaluating the influence of improved sleep on respiratory abnormalities in patients with SDB are lacking. Studies in patients with OSA, with or without obesity-hypoventilation syndrome, show that therapy with continuous positive airways pressure and non-invasive ventilation improves sleep parameters with beneficial effects on SDB. Studies involving small numbers of patients have shown that the antidepressants fluoxetine and mirtazapine produce improvements in sleep parameters and the apnoea-hypopnoea index, and that acetazolamide may improve CSA. The benzodiazepines flurazepam, temazepam and nitrazepam, the hypnotic zolpidem, the melatonin receptor agonist ramelteon and gamma-hydroxybutyrate have all been shown to improve sleep, but are not associated with reductions or worsening in SDB. It is clear that there is a distinct knowledge gap with regard to the benefit of improving sleep disturbances for subsequent improvements in SDB. Randomized controlled clinical trials investigating the effect of pharmacological and non-pharmacological improvement of sleep disorders focusing on whether there is improvement in coexisting OSA/SDB are clearly needed. Furthermore, well-designed clinical trials investigating the role of hypnotic agents in improving SDB in certain phenotypes will enable the development of treatment recommendations for primary care physicians managing these patients in routine clinical practice.

Ghrelin increases slow wave sleep and stage 2 sleep and decreases stage 1 sleep and REM sleep in elderly men but does not affect sleep in elderly women

Ghrelin increases non-REM sleep and decreases REM sleep in young men but does not affect sleep in young women. In both sexes, ghrelin stimulates the activity of the somatotropic and the hypothalamic-pituitary-adrenal (HPA) axis, as indicated by increased growth hormone (GH) and cortisol plasma levels. These two endocrine axes are crucially involved in sleep regulation. As various endocrine effects are age-dependent, aim was to study ghrelin's effect on sleep and secretion of GH and cortisol in elderly humans. Sleep-EEGs (2300-0700 h) and secretion profiles of GH and cortisol (2000-0700 h) were determined in 10 elderly men (64.0+/-2.2 years) and 10 elderly, postmenopausal women (63.0+/-2.9 years) twice, receiving 50 microg ghrelin or placebo at 2200, 2300, 0000, and 0100 h, in this single-blind, randomized, cross-over study. In men, ghrelin compared to placebo was associated with significantly more stage 2 sleep (placebo: 183.3+/-6.1; ghrelin: 221.0+/-12.2 min), slow wave sleep (placebo: 33.4+/-5.1; ghrelin: 44.3+/-7.7 min) and non-REM sleep (placebo: 272.6+/-12.8; ghrelin: 318.2+/-11.0 min). Stage 1 sleep (placebo: 56.9+/-8.7; ghrelin: 50.9+/-7.6 min) and REM sleep (placebo: 71.9+/-9.1; ghrelin: 52.5+/-5.9 min) were significantly reduced. Furthermore, delta power in men was significantly higher and alpha power and beta power were significantly lower after ghrelin than after placebo injection during the first half of night. In women, no effects on sleep were observed. In both sexes, ghrelin caused comparable increases and secretion patterns of GH and cortisol. In conclusion, ghrelin affects sleep in elderly men but not women resembling findings in young subjects.

Does mental health history explain gender disparities in insomnia symptoms among young adults?

BACKGROUND

Insomnia is the most commonly reported sleep disorder, characterized by trouble falling asleep, staying asleep, or waking up too early. Previous epidemiological data reveal that women are more likely than men to suffer from insomnia symptoms. We investigate the role that mental health history plays in explaining the gender disparity in insomnia symptoms.

METHODS

Using logistic regression, we analyze National Health and Nutritional Examination Survey (NHANES) III interview and laboratory data, merged with data on sociodemographic characteristics of the residential census tract of respondents. Our sample includes 5469 young adults (ages 20-39) from 1429 census tracts.

RESULTS

Consistent with previous research, we find that women are more likely to report insomnia symptoms compared to men (16.7% vs. 9.2%). However, in contrast to previous work, we show that the difference between women's and men's odds of insomnia becomes statistically insignificant after adjusting for history of mental health conditions (OR=1.08, p>.05).

CONCLUSIONS

The gender disparity in insomnia symptoms may be driven by higher prevalence of affective disorders among women. This finding has implications for clinical treatment of both insomnia and depression, especially among women.

Pharmacotherapy of obstructive sleep apnea

Obstructive sleep apnea (OSA) is associated with serious comorbid illnesses and diminished quality of life. At this time, continuous positive airway pressure (CPAP) therapy is the treatment of choice. However, only half of those individuals who accept CPAP are still using it at the end of one year. Furthermore, efficacy for improving self-reported sleepiness appears to be greater for patients with severe sleep apnea and severe sleepiness than other patient groups. Some patients, notwithstanding optimized therapy and therapeutic adherence continue experiencing excessive daytime somnolence. Consequently, other treatment modalities have developed, including oral appliances, surgery and pharmacotherapy. It is widely believed, albeit not empirically demonstrated, that an effective medication to treat OSA would elicit better acceptance and adherence than having to use a machine for many hours on a nightly basis. Nonetheless, paucity of data (i.e. lack of large-scale randomized controlled trials), variability of perceived and actual benefits, and adverse side-effects of the drugs thus far tested have prevented the use of pharmacotherapy until now. In this paper we review the outcome data from published trials designed to evaluate efficacy and safety of various medications proposed for treating obstructive sleep apnea.

The effect of estrogen plus progestin treatment on sleep: a randomized, placebo-controlled, double-blind trial in premenopausal and late postmenopausal women

OBJECTIVE

In this prospective randomized, placebo-controlled and double-blind study, the objective was to investigate the effects of estrogen-progestin treatment (EPT) on sleep in pre- and postmenopausal women.

DESIGN

Seventeen premenopausal (aged 45-51 years) and 18 postmenopausal (aged 58-70 years) women were studied in a sleep laboratory for two nights (one night for adaptation and one study night) before and after 6 months of treatment with EPT or placebo. During the treatment period, premenopausal women received cyclic EPT or placebo and the postmenopausal women continuous EPT or placebo. Polysomnography and questionnaires were used to evaluate sleep and well-being.

RESULTS

At the end of the treatment period, premenopausal women receiving EPT had more awakenings from stage 1 sleep (p = 0.047) and postmenopausal women with EPT had a greater total number of awakenings (p = 0.031) than the corresponding placebo group. Further, sleepiness decreased less in the premenopausal EPT group than in the placebo group (p = 0.031). In postmenopausal women, EPT decreased and placebo slightly increased slow wave activity during the second non-rapid eye movement sleep episode (p = 0.046).

CONCLUSIONS

In premenopausal and late postmenopausal women, EPT had only random and marginal effects on sleep. Although the limited findings were mostly unfavorable for EPT, one cannot conclude that EPT deteriorates sleep. Further, neither middle-aged cycling premenopausal women nor older postmenopausal women benefit from estrogen-progestin treatment in terms of their sleep quality.

Complex actions of sex steroids in adipose tissue, the cardiovascular system, and brain: Insights from basic science and clinical studies

Recent publications describing the results of the Women's Health Initiative (WHI) and other studies reporting the impact of hormone therapy on aging women have spurred reexamination of the broad use of estrogens and progestins during the postmenopausal years. Here, we review the complex pharmacology of these hormones, the diverse and sometimes opposite effects that result from the use of different estrogenic and progestinic compounds, given via different delivery routes in different concentrations and treatment sequence, and to women of different ages and health status. We examine our new and growing appreciation of the role of estrogens in the immune system and the inflammatory response, and we pose the concept that estrogen's interface with this system may be at the core of some of the effects on multiple physiological systems, such as the adipose/metabolic system, the cardiovascular system, and the central nervous system. We compare and contrast clinical and basic science studies as we focus on the actions of estrogens in these systems because the untoward effects of hormone therapy reported in the WHI were not expected. The broad interpretation and publicity of the results of the WHI have resulted in a general condemnation of all hormone replacement in postmenopausal women. In fact, careful review of the extensive literature suggests that data resulting from the WHI and other recent studies should be interpreted within the narrow context of the study design. We argue that these results should encourage us to perform new studies that take advantage of a dialogue between basic scientists and clinician scientists to ensure appropriate design, incorporation of current knowledge, and proper interpretation of results. Only then will we have a better understanding of what hormonal compounds should be used in which populations of women and at what stages of menopausal/postmenopausal life.

A systematic review of clinical trials of hormone therapy on cognitive function: effects of age at initiation and progestin use

The putative protective effects of hormone therapy (HT) have been cast in doubt by recent findings from the Women's Health Initiative Memory Study showing an increase in dementia and an increased likelihood of impaired cognitive status in women initiating HT after age 65. To explore the external generalizability of those findings to younger postmenopausal women, the medical literature was surveyed for randomized, double-blind, placebo-controlled trials of treatment with either estrogen alone or estrogen plus a progestin on neuropsychological test performance. Findings from trials in younger women (<65 years) are presented separately from those in older women (>or=65 years). This review finds little support for beneficial cognitive effects in older women of estrogen alone or in combination with progestin. However, evidence from younger women suggests potential beneficial effects in select cognitive domains, particularly among symptomatic women and recently menopausal women, and scant evidence of harm. There is a dearth of studies of the cognitive effects of estrogen plus progestin in younger women. Future studies systematically exploring the effect of age and progestin use are needed to better characterize the effects of HT on cognition in younger women. Without firm evidence of benefit to younger women, it is prudent to caution early postmenopausal women about the cognitive risks observed in WHI, recognizing the low likelihood of dementia at that age.

Investigating the effects of estradiol or estradiol/progesterone treatment on mood, depressive symptoms, menopausal symptoms and subjective sleep quality in older healthy hysterectomized women: a questionnaire study

Clinical studies have documented that estrogen treatment often ameliorates mood disturbances and depressive symptoms occurring during the menopausal transition. The relevance of gonadal hormones for mood and well-being in healthy older nondepressed women is less well understood. Fifty-one healthy hysterectomized women (mean age 64) participated in a placebo-controlled double-blind study on the effects of gonadal hormones on cognition. They received either estradiol (2 mg estradiol valerate), estradiol plus progesterone (100 mg micronized progesterone) or placebo. Mood, well being, menopausal symptoms, depressive symptoms and subjective sleep quality were measured at baseline and after 4 and 24 weeks of treatment using three questionnaires. Thirty-five women could be included into the final analysis. Strong increases in estradiol and progesterone levels occurred in response to the treatment. The two hormones, however, had no effects on mood, well-being, menopausal symptoms, sleep quality and depressive symptoms. The current small study suggests that older healthy nondepressed hysterectomized women do not react with positive or negative mood changes to estradiol or estradiol/progesterone treatment.

Insomnia in somatoform pain disorder: sleep laboratory studies on differences to controls and acute effects of trazodone, evaluated by the Somnolyzer 24 x 7 and the Siesta database

Patients with chronic pain often suffer from sleep disturbances, specifically decreased deep sleep, and thus may get into a vicious circle which maintains their pain condition. Utilizing polysomnography and psychometry, objective and subjective sleep and awakening quality was investigated in 11 patients with nonorganic insomnia (F51.0) related to somatoform pain disorder (SPD; F45.4) as compared with age- and sex-matched healthy controls of the Siesta normative database. Patients demonstrated a markedly deteriorated Pittsburgh Sleep Quality Index, a decreased Quality of Life Index, slightly increased self-reported anxiety (Zung SAS) and depression scores (Zung SDS), as well as an increased Epworth Sleepiness Scale and International Restless Legs Syndrome Scale score. Subjective sleep and awakening quality was markedly reduced, while somatic complaints were increased. Polysomnographic evaluation by a recently developed automatic sleep classifier (Somnolyzer 24 x 7) based on the rules of Rechtschaffen and Kales demonstrated reduced slow-wave sleep (SWS), the target variable in the present study, a decreased stage shift index, increased SWS latency and stage 4 sleep (S4) latency and an increased frequency of shifts from S2 to wakefulness (W) in patients as compared with controls. Minimal oxygen saturation was found decreased, periodic leg movements (PLMs) were increased. In the morning, patients showed deteriorated well-being, drive, mood and wakefulness. There were no significant noopsychic or psychophysiological differences between patients and controls (except for a reduced numerical memory and a slightly increased morning diastolic blood pressure in patients). Subsequent evaluation of the acute effects of 100 mg of a controlled-release formulation of trazodone (Trittico retard) in the patients demonstrated an increase in the target variable SWS, accompanied by a reduction in the number of awakenings and stage shifts. It normalized the frequency of shifts from S2 to W and reduced the frequency of shifts from W to S1, from S1 to S2, as well as from any stage to S1 and S2. Trazodone, however, also significantly reduced the total sleep period and S2 and increased the latency to S1. Moreover, the drug increased the reduced minimal O(2 )saturation, reduced the arousal index and the PLMs-in-wake index and normalized the increased morning diastolic blood pressure. In conclusion, our study demonstrated that SPD induced significant changes in subjective and objective sleep and awakening quality, which were partially mitigated by trazodone therapy. The data on the target variable SWS support our hypothesis of a key-lock principle in the diagnosis and drug treatment of sleep disorders. Our study provided the first evidence on the usefulness of the Somnolyzer 24 x 7 and the Siesta database in clinical practice.

Identifying target regions for vigilance improvement under hormone replacement therapy in postmenopausal syndrome patients by means of electroencephalographic tomography (LORETA)

RATIONALE

Daytime fatigue, which at the neurophysiological level is due to vigilance decrements, is a frequent complaint in postmenopausal women.

OBJECTIVES

In a three-arm, 2-month, parallel group-design study, vigilance-promoting effects of a novel continuous combination (=Climodien 2/3) of estradiol valerate (EV; 2 mg) and dienogest (DNG; 3 mg) were compared with the effects of both EV alone and placebo in 55 insomniac, postmenopausal syndrome patients.

METHODS

Low-resolution brain electromagnetic tomography (LORETA) was undertaken to identify the cerebral target regions of hormone replacement therapy.

RESULTS

An omnibus significance test revealed Climodien to increase activity in 882 of 2,394 voxels in the alpha-2 band, followed by 733, 706, and 664 voxels in the beta-2, beta-1, and beta-3 bands, and 509 voxels in the delta band, whereas 2 mg EV alone did not produce a significant suprathreshold activity. Current density increased predominantly in the right hemisphere, which had already been described in the literature as the center of the vigilance system. In the fast alpha range, which plays a major role in the context of vigilance, increased activity was found in the right prefrontal, temporal, and superior parietal cortices, i.e., those brain areas of the right-sided fronto-parietal neuronal network that are responsible for sustained attention. A further activity increase was seen in the anterior cingulate gyrus associated with attentional control and conflict monitoring. The right temporal lobe showed increased current density in all frequency bands.

CONCLUSIONS

Electroencephalographic tomography (LORETA) identified the right-hemispheric vigilance system as the target region of Climodien.

Neuroendocrine changes in sleep apnea

PURPOSE OF REVIEW

To review recent investigations examining the effects of neuroendocrine changes in obstructive sleep apnea.

RECENT FINDINGS

Gonadal hormones have long been implicated in the pathogenesis of obstructive sleep apnea. Recently, exogenous testosterone has been shown to exacerbate obstructive sleep apnea, whereas hormone replacement therapy in menopausal women may be protective in obstructive sleep apnea. Effective treatment of obstructive sleep apnea with nasal continuous positive airway pressure has been associated with improved insulin sensitivity and testicular function in individuals with obstructive sleep apnea.

SUMMARY

It is important to consider the potential development of sleep apnea in any patient who has an endocrine disorder or is receiving certain hormonal therapies. Effective assessment and management of obstructive sleep apnea with nasal continuous positive airway pressure may lead to a reduction in insulin resistance and hypertension as well as other markers of vascular risk in patients with metabolic syndrome.

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.

Brain regions activated during an auditory discrimination task in insomniac postmenopausal patients before and after hormone replacement therapy: low-resolution brain electromagnetic tomography applied to event-related potentials

Electrical sources of auditory event-related potentials (ERPs) determined by means of low-resolution brain electromagnetic tomography (LORETA) in 48 unmedicated insomniac postmenopausal patients aged between 46 and 67 years were compared with those obtained in 48 age-matched normal female controls. Subsequently, the patients were included in a double-blind, placebo-controlled, comparative, randomized 3-arm trial phase - Climodien 2/3 [estradiol valerate (EV) 2 mg + the progestin dienogest 3 mg] was compared with EV 2 mg and placebo - followed by an open-label phase in which all of them received Climodien 2/2 (EV 2 mg + dienogest 2 mg). The double-blind and the open-label phase lasted 2 months. ERPs were recorded from 19 EEG leads in a two-tone oddball paradigm and electrical sources of standard N1 and P2 as well as target N2 and P300 components were estimated. In both patients and controls, LORETA revealed an activation of the superior temporal gyrus [auditory cortex, Brodmann areas (BA) 41, 42, 22] for all four components. For standard P2, an additional activation was observed medially parietally in the precuneus (BA 7, 5). For target N2, also a medial frontal source (BA 9, 10, 32) was identified. Finally, for the target P300 component - in addition to the aforementioned sources - activations in the prefrontal cortex (BA 9, 10, 46, 47), the inferior parietal cortex (supramarginal gyrus, BA 40, 39) and the posterior cingulum (BA 31) were found. Thus, patients and controls did not differ in the structural processes engaged in these fundamental aspects of information processing. However, patients demonstrated significantly reduced source strength - for standard ERP components predominantly in the temporal lobe and for target components predominantly in the frontal lobe, indicating reduced energetic resources available for perceptual and cognitive demands of the discrimination task. While, as compared with placebo, estrogen alone had only minor effects on ERP source strength, Climodien generally increased the impressed current density at the ERP peak latencies, predominantly in the temporal lobe, indicating an increased stimulus-induced cortical arousal in the primary and higher-order auditory cortex. Specifically, Climodien enhanced P300 source strength in the left middle temporal gyrus and in the left superior frontal gyrus, brain regions that on the one hand have been shown to be affected by hormone therapy in positron emission tomography and functional magnetic resonance neuroimaging studies and that on the other hand are among those critical for encoding and memory processes.