Cushing's syndrome is associated with sleep alterations detected by wrist actigraphy

Daily associations between salivary cortisol and electroencephalographic-assessed sleep: a 15-day intensive longitudinal study

STUDY OBJECTIVES

Current evidence suggests that cortisol levels are bi-directionally associated with sleep. However, the daily, naturalistic cortisol-sleep associations remain unclear, as current evidence is mostly cross-sectional. This study tested whether pre-sleep cortisol predicts sleep duration and quality, and whether these sleep parameters predict the following day's diurnal cortisol slope using a 15-day intensive longitudinal design with electroencephalographic measures and saliva sampling.

METHODS

Ninety-five young adults (Mage = 20.48 ± 1.59 years) provided saliva samples at awakening and pre-sleep over 14 consecutive days, providing 2345 samples (85% viable). The Z-Machine Insight + was used to record over 900 nights of total sleep time (TST) and sleep efficiency (SE). Multilevel models tested these data at the between- and within-person levels.

RESULTS

Higher pre-sleep cortisol predicted shorter TST (p < .001) and lower SE (p < .001) at the within-person level. Individuals with shorter average TST (p = .007) or lower average SE (p < .001) had flatter diurnal cortisol slopes, compared to those with longer average TST or higher average SE. Follow-up analyses showed that individuals with shorter average TST (vs. longer average TST) had higher pre-sleep cortisol levels (p = .01).

CONCLUSIONS

Our findings provide evidence that pre-sleep cortisol is associated with sleep duration and quality at the within-individual level. Furthermore, individuals with short or poor sleep had flatter diurnal cortisol slopes. Although the effect sizes are small, these findings show the naturalistic associations between sleep and cortisol in a relatively healthy sample. These findings suggest that sleep maintains the regulation of the stress-response system, which is protective against mental and physical disorders.

Sleep disruption in patients with active and treated endogenous Cushing's syndrome

CONTEXT

The hypothalamic-pituitary-adrenal axis is a critical regulator of circadian rhythm in humans. Impaired sleep adversely affects metabolic, emotional, and cognitive health.

OBJECTIVE

To characterize sleep disturbances in patients with active and treated Cushing's syndrome (CS), and identify factors associated with impaired sleep in treated patients.

DESIGN

Single-center cross-sectional study.

METHODS

Patients with pituitary or adrenal CS enrolled in an observational study completed Nottingham Health Profile (NHP), CushingQoL, and Hospital Anxiety and Depression assessments. Cross-sectional analysis was conducted including patients with active and treated disease.

RESULTS

113 (94 female) patients with CS were included, 104 pituitary and 9 adrenal, with mean age at diagnosis of 43.9 ± 13.4 years. Mean and maximum duration of follow up was 5.1 and 23 years. Mean NHP sleep score was lower (i.e., improved) in patients with treated vs. active disease (29.6 ± 30.2 vs. 51.9 ± 30.9, p = 0.0005), as was CushingQoL sleep score (p = 0.015), but 41.5% of patients with treated disease stated they often or always had trouble sleeping. The proportion of treated vs. active patients taking medication for sleep, mood, or pain was not different. Neither NHP nor CushingQoL pain scores were lower in treated vs. active patients (p = 0.39 and 0.53). In patients with treated CS, anxiety and depression correlated with worse sleep scores.

CONCLUSIONS

Patients with treated CS report improved sleep quality compared to those with active disease, but almost half of treated patients still report sleep challenges. The need for sleep medications, reported by one third of patients, was not different after CS treatment. Ongoing mood disturbances may play a role in persistent sleep disruption. Further work should focus on determinants of sleep impairments in treated CS patients.

The relations of circulating agouti-related peptide and leptin with altered sleep architecture in patients with active Cushing's disease: a pilot study

AIM

To evaluate sleep architecture of patients with Cushing's disease (CD) and to explore whether agouti-related peptide (AgRP) and/or leptin play a permissive role in sleep alterations in patients with active CD.

METHODS

We performed polysomnography on 26 patients with active CD and age 26 age- and sex-matched control subjects. Blood samples were obtained from all participants for the analyzes of AgRP and leptin. The laboratory and sleep-related parameters were compared.

RESULTS

The groups were similar in age, gender, and body mass index. The CD group had reduced sleep efficiency (71.6 ± 12.1% vs. 78.8 ± 12.6%, p = 0.042) and increased wake after sleep onset (WASO%) (24.7 ± 13.1% vs. 17.4 ± 11.6%, p = 0.040) as compared to control group. Seventeen patients with CD (65.4%) and 18 control subjects (69.2%) had obstructive sleep apnea. Serum AgRP (13.2 ± 7.4 pg/ml vs. 9 ± 3.1, p = 0.029), leptin (59.5 mcg/l, [IQR] 32.6-94.6 vs. 25.3 mcg/l, [IQR] 12.9-57.5, p = 0.007) were higher in CD group. AgRP and leptin correlated negatively with total sleep time, sleep efficiency, stage N2 sleep (%), and positively with WASO%. In multiple regression analyses, serum cortisol (ß =  - 0.359, p = 0.042) and AgRP (ß =  - 0.481, p = 0.01) were significant predictor of sleep efficiency. AgRP was also significant predictor of WASO% (ß = 0.452 and p < 0.05).

CONCLUSIONS

Active CD carries an increased risk of impaired sleep efficiency and continuity which may worsen health-related quality of life. Elevated circulating AgRP and, to a lesser extent, leptin may be associated with decreased sleep efficiency and continuity in patients with CD. Patients with CD who have subjective sleep symptoms should be screened with polysomnography.

Childhood diabetes and sleep

Sleep modulates glucose metabolism, both in healthy states and in disease. Alterations in sleep duration (insufficient and excessive) and obstructive sleep apnea may have reciprocal ties with obesity, insulin resistance and Type 2 diabetes, as demonstrated by emerging evidence in children and adolescents. Type 1 diabetes is also associated with sleep disturbances due to the influence of wide glycemic fluctuations upon sleep architecture, the need to treat nocturnal hypoglycemia, and the need for glucose monitoring and insulin delivery technologies. In this article, we provide an extensive and critical review on published pediatric literature regarding these topics, reviewing both epidemiologic and qualitative data, and provide an overview of the pathophysiology linking sleep with disorders of glucose homeostasis.

Women with abuse-related PTSD sleep more fitfully but just as long as healthy controls: an actigraphic study

STUDY OBJECTIVES

Subjective reports of sleep impairments are common in individuals with posttraumatic stress disorder (PTSD), but objective assessments of sleep have yielded mixed results.

METHODS

We investigated sleep via actigraphy and e-diary on 6 consecutive nights in a group of 117 women with PTSD after childhood abuse (CA; PTSD group), a group of 31 mentally healthy women with a history of CA (healthy trauma controls, HTC group) and a group of 36 non-traumatized mentally healthy women (healthy controls, HC group).

RESULTS

The PTSD group reported lower sleep quality, more nights with nightmares, and shorter sleep duration than both HTC and HC. Actigraphic measures showed more and longer sleep interruptions in the PTSD group compared to HTC and HC, but no difference in sleep duration. While the PTSD group underestimated their sleep duration, both HTC and HC overestimated their sleep duration. HTC did not differ from HC regarding sleep impairments.

CONCLUSIONS

Sleep in women with PTSD after CA seems to be more fragmented but not shorter compared to sleep patterns of mentally healthy control subjects. The results suggest a stronger effect of PTSD psychopathology on sleep compared to the effect of trauma per se.

Cushing Syndrome is Associated with Increased Stage N2 Sleep and Decreased SWS Partially Reversible After Treatment

The aim of the present study was to evaluate the sleep parameters of patients with Cushing syndrome (CS) at the time of diagnosis and 12-months after treatment. Thirty four newly diagnosed patients with endogenous CS (17 with ACTH-secreting pituitary adenoma, 17 with adrenal CS) and 23 controls with similar age were included in the study. Two polysomnography (PSG) recordings were performed; one at the time of diagnosis and the other 12 months after resolution of hypercortisolemia. Control group had only baseline PSG. Based on the PSG findings, stage N2 sleep was found to be prolonged, stage N3 and REM sleep were shortened in patients with CS. Average heart rate and mean Apnea Hypopnea Index (AHI) score were higher in patients with CS than the control subjects. Sixteen (47.1%) patients with CS and 4 (17.4%) controls had obstructive sleep apnea (OSA; AHI ≥5). There were no significant differences in sleep parameters of patients according to the etiology of CS (adrenal vs. pituitary) patients. Following 12-months of treatment, a significant decrease in stage N2 sleep and a significant increase in stage N3 sleep were detected, but there was no change in terms of AHI. In conclusion, Cushing syndrome has disturbing effects on sleep structure and these effects are at least partially reversible after treatment. However, the increased risk of OSA was not reversed a year after treatment indicating the importance of early diagnosis and treatment of CS.

Closed-Loop Fuzzy Energy Regulation in Patients With Hypercortisolism via Inhibitory and Excitatory Intermittent Actuation

Hypercortisolism or Cushing's disease, which corresponds to the excessive levels of cortisol hormone, is associated with tiredness and fatigue during the day and disturbed sleep at night. Our goal is to employ a wearable brain machine interface architecture to regulate one's energy levels in hypercortisolism. In the present simulation study, we generate multi-day cortisol profile data for ten subjects both in healthy and disease conditions. To relate an internal hidden cognitive energy state to one's cortisol secretion patterns, we employ a state-space model. Particularly, we consider circadian upper and lower bound envelopes on cortisol levels, and timings of hypothalamic pulsatile activity underlying cortisol secretions as continuous and binary observations, respectively. To estimate the hidden cognitive energy-related state, we use Bayesian filtering. In our proposed architecture, we infer one's cognitive energy-related state using wearable devices rather than monitoring the brain activity directly and close the loop utilizing fuzzy control. To model actuation in the real-time closed-loop architecture, we simulate two types of medications that result in increasing and decreasing the energy levels in the body. Finally, we close the loop using a knowledge-based control approach. The results on ten simulated profiles verify how the proposed architecture is able to track the energy state and regulate it using hypothetical medications. In a simulation study based on experimental data, we illustrate the feasibility of designing a wearable brain machine interface architecture for energy regulation in hypercortisolism. This simulation study is a first step toward the ultimate goal of managing hypercortisolism in real-world situations.

Meta-analysis of age and actigraphy assessed sleep characteristics across the lifespan

STUDY OBJECTIVES

Sleep quantity and continuity vary across the lifespan. Actigraphy is a reliable and widely-used behavioral measure of sleep in research and personal health monitoring. This meta-analysis provides a novel examination of whether age (in years) is associated with actigraphy-assessed sleep across the lifespan.

METHODS

A systematic search of PubMed, Embase.com, Cochrane CENTRAL, and PsycINFO using "actigraphy" and "sleep" terms provided 7,079 titles/abstracts; studies of individuals with known psychiatric or medical comorbidities were excluded. Ninety-one articles (N = 23,365) provided data for six meta-analyses examining sleep duration (k = 89), sleep efficiency (k = 58), bedtime (k = 19) and waketime (k = 9) for individuals ages 6-21, and bedtime (k = 7) and waketime (k = 7) for individuals ages 22 and older.

RESULTS

At older ages, sleep duration was shorter (r = -0.12) and sleep efficiency was lower (r = -0.05). Older age was associated with later bedtime (r = 0.37) and wake-up time (r = 0.24) from ages 6-21, whereas older age was associated with earlier bedtime (r = -0.66) and wake-up time (r = -0.59) for ages 22 and above. The strength of these associations was modified by study continent, but not by any other moderator.

CONCLUSIONS

Age was negatively associated with actigraphy-assessed sleep duration and efficiency, but the effects were small in magnitude. On the other hand, large associations were observed between age and sleep timing, despite a smaller literature and the absence of analyzable data for ages 30-60. Changes in sleep timing, rather than changes in sleep duration or continuity, may better characterize the effects of age on human sleep.

Mental Health in Patients With Adrenal Incidentalomas: Is There a Relation With Different Degrees of Cortisol Secretion?

CONTEXT

Cushing's syndrome frequently causes mental health impairment. Data in patients with adrenal incidentaloma (AI) are lacking.

OBJECTIVE

We aimed to evaluate psychiatric and neurocognitive functions in AI patients, in relation to the presence of subclinical hypercortisolism (SH), and the effect of adrenalectomy on mental health.

DESIGN

We enrolled 62 AI patients (64.8 ± 8.9 years) referred to our centers. Subclinical hypercortisolism was diagnosed when cortisol after 1mg-dexamethasone suppression test was >50 nmol/L, in the absence of signs of overt hypercortisolism, in 43 patients (SH+).

INTERVENTIONS

The structured clinical interview for the Diagnostic and Statistical Manual of Mental Disorders-5, and 5 psychiatric scales were performed. The Brief Assessment of Cognition in Schizophrenia (Verbal and Working Memory, Token and Symbol Task, Verbal Fluency, Tower of London) was explored in 26 patients (≤65 years).

RESULTS

The prevalence of psychiatric disorders was 27.4% (SH+ 30.2% vs SH- 21.1%, P = 0.45). SH+ showed a higher prevalence of middle insomnia (by the Hamilton Depression Rating Scale) compared with SH- (51% vs 22%, P = 0.039). Considering the Sheehan Disability Scale, SH+ showed a higher disability score (7 vs 3, P = 0.019), higher perceived stress (4.2 ± 1.9 vs 2.9 ± 1.9, P = 0.015), and lower perceived social support (75 vs 80, P = 0.036) than SH-. High perceived stress was independently associated with SH (odds ratio [OR] = 5.46, confidence interval 95% 1.4-21.8, P = 0.016). Interestingly, SH+ performed better in verbal fluency (49.5 ± 38.9 vs 38.9 ± 9.0, P = 0.012), symbol coding (54.1 ± 6.7 vs 42.3 ± 15.5, P = 0.013), and Tower of London (15.1 vs 10.9, P = 0.009) than SH-. In 8 operated SH+, no significant changes were found.

CONCLUSIONS

Subclinical hypercortisolism may influence patients' mental health and cognitive performances, requiring an integrated treatment.

Psychiatric and neurocognitive consequences of endogenous hypercortisolism

Psychiatric and neurocognitive symptoms due to hypercortisolism were already described by Harvey Cushing in his original paper on patients with Cushing's syndrome (CS). Nowadays, it is well known that psychiatric and cognitive complaints are two of the most common, and most distressing, symptoms in patients with CS. Psychiatric symptoms are indeed a major clinical manifestation of CS. The most commonly observed psychiatric conditions are depression and anxiety, whilst mania and psychosis are less common. Several domains of cognitive function are impaired at diagnosis, including episodic and working memory, executive function and attention. Following treatment, one-fourth of the patients still experience depressed mood, and the cognitive impairments are only partially restored. Consequently, quality of life in patients with CS is severely and persistently affected. Neuroimaging studies have also illustrated the deleterious effects of hypercortisolism on the brain by demonstrating reduced grey matter volumes and cortical thickness, altered resting-state functional responses and during cognitive tasks, as well as widespread reduced white matter integrity, especially in structures important for cognitive function and emotional processing, both before and after successful abrogation of hypercortisolism. In this paper, we summarize the current knowledge on the psychiatric and neurocognitive consequences of hypercortisolism in patients with CS, both before, and after successful treatment. In addition, we review the structural and functional brain abnormalities associated with hypercortisolism and discuss the influence of these factors on quality of life.

The association between physical activity, sleep, and quality of life in patients in bio-chemical remission from Cushing's syndrome

PURPOSE

Cushing's syndrome can negatively affect patient's quality of life (QoL) after treatment and remission. Exposure to increased cortisol over time can result in visceral obesity, which makes this population vulnerable to cardiovascular risk factors associated with visceral obesity. Sleep disturbances are present in patients in remission from Cushing's syndrome, impacting QoL. Moderate intensity physical activity performed 3 times a week decreases visceral obesity and improves sleep quality, therefore, engaging in physical activity after remission may improve patient's QoL. The current study aims to explore the association between sleep quality, physical activity, and QoL in patients in remission of Cushing's syndrome.

METHODS

Patients in bio-chemical remission from Cushing's syndrome (N = 147) were recruited through the Cushing's Support and Research Foundation. Quality of life was assessed using the Cushing Quality of Life Questionnaire (CushingQoL), sleep was assessed with the Pittsburgh Sleep Quality Index (PSQI), and physical activity levels were assessed with the Godin-Sheppard Leisure-Time Physical Activity Questionnaire (GSLTPAQ).

RESULTS

Sleep quality was significantly associated with both subscales of the CushingQoL (both p < .001), but physical activity was not significantly associated with either subscale. Sleep was not significantly associated with physical activity engagement in this sample.

CONCLUSION

Results suggest that patients in remission from Cushing's syndrome experience sleep disturbances that are significantly associated with impaired QoL. Future research should focus on ameliorating the persisting clinical features of Cushing's syndrome that are associated with impaired QoL after bio-chemical remission to improve QoL and expedite complete functional remission.

A Cortisol-Based Energy Decoder for Investigation of Fatigue in Hypercortisolism

Hormones play a fundamental role in homeostasis. We develop a state-space model relating the body's internal energy to cortisol hormone secretions. Cortisol is secreted in pulses and follows a 24 h circadian rhythm. Secretory event timings carry important information regarding internal feedback signaling taking place, as do the upper and lower serum cortisol levels. We relate an internal energy state variable to cortisol pulse timings and to the upper and lower serum cortisol envelopes. We derive Bayesian filter equations for state estimation and use the Expectation-Maximization algorithm for model parameter recovery. Results on multi-day simulated data show circadian energy variations in healthy subjects and non-circadian fluctuations throughout 24 h periods in patient models suffering from hypercortisolism. The results shed new light on why patients diagnosed with excess cortisol disorders frequently experience symptoms of daytime fatigue and sleep disturbances at night. The state-space model is also an important first step towards the design of closed-loop controllers for treating hormone-related disorders in a manner that closely emulates the body's own pulsatile feedback mechanisms.

Pituitary diseases and sleep disorders

PURPOSE OF REVIEW

Patients with pituitary diseases have decreased quality of life. Sleep disorders are prevalent among patients with pituitary diseases and contribute to decreased quality of life.

RECENT FINDINGS

Patients previously treated for compression of the optic chiasm by surgery, and in some cases postoperative radiotherapy, suffer from sleep disorders. These are characterized by decreased sleep quality, delayed onset of sleep, and daytime sleepiness. Circumstantial evidence suggests that this may be caused by hypothalamic dysfunction. A challenging speculation is that previous compression of the optic chiasm compromised the function of the retinohypothalamic tract. Through this tract the eyes convey information on day-night cycles to the hypothalamic nuclei. Patients with acromegaly, even despite biochemical control, suffer frequently from obstructive sleep apnea. Patients with Cushing's disease suffer from fragmented sleep, sleep apnea, and snoring. Prolactinomas do not seem to affect sleep characteristics. The association between appropriately substituted pituitary insufficiency and sleep disorders is less clear. The effects of recombinant human growth hormone on sleep characteristics in adults are inconsistent.

SUMMARY

Pituitary disorders are associated with different sleep disorders. Different studies point to irreversible changes in sleep-wake rhythmicity in patients treated previously for pituitary tumors with chiasm compression. VIDEO ABSTRACT.