Erectile dysfunction in a murine model of sleep apnea

Exploring the link between comorbid insomnia and sleep apnea (COMISA) and erectile dysfunction: implications for male sexual health

INTRODUCTION

This review explores the interplay between comorbid insomnia and sleep apnea (COMISA) and erectile dysfunction (ED), 2 conditions that significantly impact men's health. COMISA, a recently recognized condition characterized by the coexistence of insomnia and obstructive sleep apnea, has been shown to disrupt sleep architecture and cause intermittent hypoxia. These disturbances are increasingly linked to the exacerbation of ED, a prevalent issue among men. Understanding the connection between COMISA and ED is crucial for developing integrated treatment approaches that address both sleep and sexual health.

OBJECTIVES

We aim to explore the epidemiological, physiological, and potential therapeutic intersections of COMISA and ED. This review sets out to develop a better understanding of the relationship between these conditions and to emphasize the need for an integrated diagnostic and therapeutic approach that addresses both sleep and sexual health.

METHODS

Through a comprehensive analysis, including a detailed examination of extant studies, we address the hormonal imbalances and alterations in neural pathways that collectively contribute to the complex pathophysiology of ED and how these are particularly susceptible to the concurrent presence of COMISA.

RESULTS

Our analysis indicates that disruptions in sleep architecture and intermittent hypoxia associated with COMISA can exacerbate ED. Hormonal imbalances, endothelial dysfunction, autonomic imbalance, and increased inflammation and oxidative stress are key mechanisms through which COMISA influences ED. These factors collectively impair vascular health, reduce testosterone levels, disrupt neural control of erections, and contribute to the severity of ED.

CONCLUSIONS

This review underscores the necessity for an integrated approach to diagnosis and therapy that considers both sleep and sexual health to improve overall outcomes. These insights should foster a deeper understanding of the relationship between COMISA and ED, encourage further research in this area, and potentially lead to the development of innovative treatment strategies to manage these closely intertwined health concerns.

Identification of fibrosis-related genes and biomarkers in diabetic erectile dysfunction

Background

Diabetic erectile dysfunction (DMED) has a high incidence and is poorly treated.

Aim

This study investigates fibrosis's genetic profiling and explores potential mechanisms for DMED.

Methods

The DMED model was constructed in rats using streptozotocin. Erectile function was quantified using cavernous nerve electrostimulation. Fibrosis was evaluated using Masson's staining. RNA-seq was employed to analyze differentially expressed genes and fibrosis-related genes (FRGs) were acquired. Function enrichment analyses were performed, and genetic interaction was analyzed. Hub FRGs were screened using machine learning algorithms and Cytoscape tools and validated in Gene Expression Omnibus databases. Moreover, biological roles and subpopulation distribution of hub FRGs were determined.

Outcomes

Fibrosis-related genetic functions may play a vital role in DMED.

Results

Based on comprehensive analysis, 45 differentially expressed FRGs were identified. These genes participate in regulating smooth muscle cell proliferation, vasoconstriction, and collagen-associated activities. Final analyses identified and validated a core gene signature comprising TIMP1, BMP7, and POSTN. They were closely associated with diabetic complications-related signaling pathways and extracellular matrix-receptor interaction.

Clinical Translation

The identified fibrosis-related gene signature may serve as the novel biomarkers for treating DMED.

Strengths and Limitations

The study is the first to investigate the genetic profiles behind fibrosis and DMED using comprehensive approaches. However, the validation is not adequate and more animal experiments are needed.

Conclusion

The gene profiling and biological functions of FRGs in DMED were identified. These results broaden the understanding of fibrosis in DMED.

Neuropsychiatric Behavioral Assessments in Mice After Acute and Long-Term Treatments of Low-Intensity Pulsed Ultrasound

Introduction: To evaluate whether both acute and chronic low-intensity pulsed ultrasound (LIPUS) affect brain functions of healthy male and female mice. Methods: Ultrasound (frequency: 1.5 MHz; pulse: 1.0 kHz; spatial average temporal average (SATA) intensity: 25 mW/cm2; and pulse duty cycle: 20%) was applied at mouse head in acute test for 20 minutes, and in chronic experiment for consecutive 10 days, respectively. Behaviors were then evaluated. Results: Both acute and chronic LIPUS at 25 mW/cm2 exposure did not affect the abilities of movements, mating, social interaction, and anxiety-like behaviors in the male and female mice. However, physical restraint caused struggle-like behaviors and short-time memory deficits in chronic LIPUS groups in the male mice. Conclusion: LIPUS at 25 mW/cm2 itself does not affect brain functions, while physical restraint for LIPUS therapy elicits struggle-like behaviors in the male mice. An unbound helmet targeted with ultrasound intensity at 25-50 mW/cm2 is proposed for clinical brain disease therapy.

Exploring the potential relationships among obstructive sleep apnea, erectile dysfunction, and gut microbiota: a narrative review

INTRODUCTION

Poor sleep quality is closely associated with comorbidities affecting a multitude of organ systems. Among the sleep disorders in the population, there has recently been an increase in the prevalence of obstructive sleep apnea (OSA), which has particularly affected men. The intermittent hypoxia and sleep fragmentation associated with OSA can result in the manifestation or aggravation of a number of pathophysiologic conditions, including the impairment of reproductive function in men and women. In this context, erectile dysfunction (ED) is of particular concern. Other consequences of OSA are changes in the gastrointestinal microbiota, with the resultant dysbiosis having potentially harmful consequences that promote downstream exacerbation of various comorbidities.

OBJECTIVES

This narrative review aims to explore the potential relationships among ED, gut microbiota, and OSA.

METHODS

A search of the relevant literature was performed in the PubMed, Embase, Medline, and Web of Science databases.

RESULTS

Sleep is important for regulating the body's functions, and sleep deprivation can negatively affect health. OSA can damage organic functions, including reproductive function, and can lead to ED. Restoring the microbiota and improving sleep can help to improve sexual function or reverse ED and enhance other associated conditions mediated through the gut-brain axis relationship. Probiotics and prebiotics can be used as supportive strategies in the prevention and treatment of OSA, as they help to reduce systemic inflammation and improve intestinal barrier function.

CONCLUSION

A good diet, a healthy lifestyle, and proper bowel function are essential in controlling depression and several other pathologies. Modulating the gut microbiota through probiotics and prebiotics can provide a viable strategy for developing new therapeutic options in treating many conditions. A better understanding of these a priori unrelated phenomena would foster our understanding of the effects of OSA on human fertility and how changes in gut microbiota may play a role.

Impact of hypoxia on male reproductive functions

Male reproductive functions, which include testicular steroidogenesis, spermatogenesis, and sexual/erectile functions are key in male fertility, but may be adversely altered by several factors, including hypoxia. This review demonstrates the impact of hypoxia on male reproductive functions. Acute exposure to hypoxia promotes testosterone production via stimulation of autophagy and upregulation of steroidogenic enzymes and voltage-gated L-type calcium channel, nonetheless, chronic exposure to hypoxia impairs steroidogenesis via suppression of the hypothalamic-pituitary-testicular axis. Also, hypoxia distorts spermatogenesis and reduces sperm count, motility, and normal forms via upregulation of VEGF and oxidative stress-sensitive signaling. Furthermore, hypoxia induces sexual and erectile dysfunction via a testosterone-dependent downregulation of NO/cGMP signaling and upregulation of PGE1/TGFβ1-driven penile endothelial dysfunction. Notably, hypoxia programs male sexual function and spermatogenesis/sperm quality via feminization and demasculinization of males and oxidative stress-mediated alteration in sperm DNA methylation. Since oxidative stress plays a central role in hypoxia-induced male reproductive dysfunction, studies exploring the effects of antioxidants and upregulation of transcription of antioxidants on hypoxia-induced male reproductive dysfunction are recommended.

Impaired Human Sexual and Erectile Function Affecting Semen Quality, in Obstructive Sleep Apnea: A Pilot Study

Obstructive sleep apnea (OSA) is a rising problem, with important implications for public health. Recent evidence has revealed a link between OSA and reduced male fertility. We investigated the association between OSA and sexual and erectile function, as well as semen quality, and the effect of treatment by continuous positive airway pressure (CPAP). A total of 41 male subjects, who underwent polysomnography for suspected OSA, participated in the study. Erectile and sexual function were assessed with the 15-item International Index of Erectile Function (IIEF-15) questionnaire, blood samples, and sperm analysis. OSA patients after the initiation of CPAP treatment were followed for a period of 1 year. Thirty-two patients were diagnosed with OSA, and nine subjects without OSA were used as a control group. OSA patients demonstrated significantly impaired erectile function, reduced testosterone levels, and lower semen quality. Multivariable regression analysis showed that BMI and IIEF score were independent determinants of AHI. Sexual function improved after a year of CPAP therapy in OSA patients. This study provides further evidence regarding the association between OSA and erectile function impairment, as well as semen quality. Longitudinal adherence to CPAP treatment has a beneficial effect on erectile function.

Obstructive Sleep Apnea Affects Lacrimal Gland Function

Purpose

To determine the effect of obstructive sleep apnea syndrome (OSA) on lacrimal gland function and its mechanism.

Methods

Male mice aged seven to eight weeks were housed in cages with cyclic intermittent hypoxia to mimic OSA, and the control group was kept in a normal environment. Slit-lamp observation, fluorescein staining, and corneal sensitivity detection are used to assess cornea changes. Tear secretion was detected by phenol red cotton thread, and the pathological changes of lacrimal gland were observed by hematoxylin and eosin staining, oil red O staining, cholesterol and triglyceride kits, immunofluorescence staining, immunohistochemical staining, real-time polymerase chain reaction, transmission electron microscopy, and Western blot.

Results

Studies revealed a decreased tear secretion, corneal epithelial defects and corneal hypersensitivity. Myoepithelial cell damage, abnormal lipid accumulation, reduced cell proliferation, increased apoptosis and inflammatory cell infiltration in the lacrimal gland were also seen. Hifα and NF-κB signaling pathways, moreover, were activated, while Pparα was downregulated, in the lacrimal glands of OSA mice. Fenofibrate treatment significantly alleviated pathological changes of the lacrimal gland induced by OSA.

Conclusion

OSA disturbs the Hifα/Pparα/NF-κB signaling axis, which affects lacrimal gland structure and function and induces dry eye.

Potential Effect of the Circadian Clock on Erectile Dysfunction

The circadian rhythm is an internal timing system, which is generated by circadian clock genes. Because the circadian rhythm regulates numerous cellular, behavioral, and physiological processes, organisms have evolved with intrinsic biological rhythms to adapt the daily environmental changes. A variety of pathological events occur at specific times, while disturbed rhythms can lead to metabolic syndrome, vascular dysfunction, inflammatory disorders, and cancer. Therefore, the circadian clock is considered closely related to various diseases. Recently, accumulated data have shown that the penis is regulated by the circadian clock, while erectile function is impaired by an altered sleep-wake cycle. The circadian rhythm appears to be a novel therapeutic target for preventing and managing erectile dysfunction (ED), although research is still progressing. In this review, we briefly summarize the superficial interactions between the circadian clock and erectile function, while focusing on how disturbed rhythms contribute to risk factors of ED. These risk factors include NO/cGMP pathway, atherosclerosis, diabetes mellitus, lipid abnormalities, testosterone deficiency, as well as dysfunction of endothelial and smooth muscle cells. On the basis of recent findings, we discuss the potential role of the circadian clock for future therapeutic strategies on ED, although further relevant research needs to be performed.

Erectile Dysfunction and Obstructive Sleep Apnea: A Review

Erectile dysfunction (ED) is a disease with a wide scope of etiologies. Obstructive sleep apnea (OSA) is considered one of the risk factors for ED and is less studied. A growing lot of evidence show an association between OSA and ED. This study provides an updated review of the relationship between ED and OSA and the possible physiological mechanisms of ED in patients with OSA based on the current evidence. In clinical interviews, patients with ED may benefit from a sleep evaluation. However, further clinical investigations and more basic research are needed to illustrate the relationship between ED and OSA.

Prevalence and Characteristics of Erectile Dysfunction in Obstructive Sleep Apnea Patients

BACKGROUND

Obstructive sleep apnea (OSA) is a common and severe social problem. Erectile dysfunction (ED) is an important health concern. The prevalence of OSA with ED is increasing, which significantly affects the quality of life and work efficiency of patients. However, the mechanism underlying the comorbidity of these two diseases remains unclear.

OBJECTIVES

(1) Investigate the prevalence of OSA with ED; (2) analyze the correlation between OSA and ED; and (3) explore the treatment response to and possible mechanism of uvulapalatopharyngoplasty (UPPP) in patients with OSA and ED. This study aims to provide a theoretical basis for the clinical diagnosis and comprehensive treatment of OSA with ED and improve prevention and treatment strategies.

MATERIALS AND METHODS

In total, 135 subjects were enrolled in the study. Clinical data, polysomnography, the ESS score, Beck anxiety score, Beck depression score, IIEF-5 score and ASEX score were recorded before UPPP and 6 months after UPPP. Sex hormones were measured for all subjects using a Roche electrochemiluminescence analyzer.

RESULT

The prevalence of OSA with ED was 64.52%, and the prevalence of severe OSA with ED was 73.02%. The prevalence of OSA with ED increased with age, BMI and apnea-hypopnea index (AHI) value. Among polysomnography indicators, minimum oxygen saturation and average oxygen saturation may predict the occurrence of OSA with ED. Improving the patient's anxiety and depression is very important for treating OSA with ED. Sex hormone levels were not significantly correlated with the occurrence of OSA with ED.

CONCLUSION

ED is a common symptom of OSA patients. This study showed that sex hormone levels in OSA patients with ED were not significantly correlated with the condition, but further investigation of this relationship is worthwhile. It is recommended that the free and combined types of sex hormones be further distinguished during testing because the free type is the active form. UPPP surgical treatment is effective for OSA with ED, and its possible mechanism is protection of the peripheral nerves of the sex organs by improving nighttime hypoxia and arousal.

Obstructive sleep apnea increases risk of female infertility: A 14-year nationwide population-based study

OBJECTIVES

To determine the risk of having OSA in a cohort of female subjects who are infertile and the odds of being infertile in women with OSA.

PATIENTS AND METHODS

A nationwide, case-control study of female patients 20 years or older diagnosed with female infertility living in Taiwan, from January 1, 2000, through December 31, 2013 (N = 4,078). We identified women who were infertile and created a 2:1 matched control group with women who were not infertile. We used multivariable logistic regression analysis to further estimate the effects of OSA on female infertility.

RESULTS

In this 14- year retrospective study, we included 4,078 patients having an initial diagnosis of female infertility. Of those women with infertility, 1.38% had a history of OSA compared with 0.63% of fertile controls (p = 0.002). The mean ages in the study groups were 32.19 ± 6.20 years, whereas the mean ages in the control groups were 32.24 ± 6.37years. Women with OSA had 2.101- times the risk of female infertility compared to women without OSA (p<0.001).

CONCLUSION

Our study showed that OSA is more commonly seen in infertile women and increases the odds that a woman will be infertile. More studies need to be done on the whether or not diagnosing and treating OSA can decrease the rate of infertility.

High altitude exposure affects male reproductive parameters: Could it also affect the prostate?†

Living at high altitudes and living with prostatic illness are two different conditions closely related to a hypoxic environment. People at high altitudes exposed to acute, chronic, or intermittent hypobaric hypoxia turn on several mechanisms at the system, cellular and molecular level to cope with oxygen atmosphere scarcity maintaining the oxygen homeostasis. This exposure affects the whole organism and function of many systems, such as cardiovascular, respiratory, and reproductive. On the other hand, malignant prostate is related to the scarcity of oxygen in the tissue microenvironment due to its low availability and high consumption due to the swift cell proliferation rates. Based on the literature, this similarity in the oxygen scarcity suggests that hypobaric hypoxia, and other common factors between these two conditions, could be involved in the aggravation of the pathological prostatic status. However, there is still a lack of evidence in the association of this disease in males at high altitudes. This review aims to examine the possible mechanisms that hypobaric hypoxia might negatively add to the pathological prostate function in males who live and work at high altitudes. More profound investigations of hypobaric hypoxia's direct action on the prostate could help understand this exposure's effect and prevent worse prostate illness impact in males at high altitudes.

Effects of Environmental and Pathological Hypoxia on Male Fertility

Male infertility is a widespread health problem affecting approximately 6%-8% of the male population, and hypoxia may be a causative factor. In mammals, two types of hypoxia are known, including environmental and pathological hypoxia. Studies looking at the effects of hypoxia on male infertility have linked both types of hypoxia to poor sperm quality and pregnancy outcomes. Hypoxia damages testicular seminiferous tubule directly, leading to the disorder of seminiferous epithelium and shedding of spermatogenic cells. Hypoxia can also disrupt the balance between oxidative phosphorylation and glycolysis of spermatogenic cells, resulting in impaired self-renewal and differentiation of spermatogonia, and failure of meiosis. In addition, hypoxia disrupts the secretion of reproductive hormones, causing spermatogenic arrest and erectile dysfunction. The possible mechanisms involved in hypoxia on male reproductive toxicity mainly include excessive ROS mediated oxidative stress, HIF-1α mediated germ cell apoptosis and proliferation inhibition, systematic inflammation and epigenetic changes. In this review, we discuss the correlations between hypoxia and male infertility based on epidemiological, clinical and animal studies and enumerate the hypoxic factors causing male infertility in detail. Demonstration of the causal association between hypoxia and male infertility will provide more options for the treatment of male infertility.

Obstructive Sleep Apnea Is Associated With Low Testosterone Levels in Severely Obese Men

Background

Disrupted sleep affects cardio-metabolic and reproductive health. Obstructive sleep apnea syndrome represents a major complication of obesity and has been associated with gonadal axis activity changes and lower serum testosterone concentration in men. However, there is no consistent opinion on the effect of obstructive sleep apnea on testosterone levels in men.

Objective

The aim of this study was to determine the influence of obstructive sleep apnea on total and free testosterone levels in severely obese men.

Materials and methods

The study included 104 severely obese (Body Mass Index (BMI) ≥ 35 kg/m2) men, aged 20 to 60, who underwent anthropometric, blood pressure, fasting plasma glucose, lipid profile, and sex hormone measurements. All participants were subjected to polysomnography. According to apnea-hypopnea index (AHI) patients were divided into 3 groups: <15 (n = 20), 15 - 29.9 (n = 17) and ≥ 30 (n = 67).

Results

There was a significant difference between AHI groups in age (29.1 ± 7.2, 43.2 ± 13.2, 45.2 ± 10.2 years; p < 0.001), BMI (42.8 ± 5.9, 43.2 ± 5.9, 47.1 ± 7.8 kg/m2; p = 0.023), the prevalence of metabolic syndrome (MetS) (55%, 82.4%, 83.6%, p = 0.017), continuous metabolic syndrome score (siMS) (4.01 ± 1.21, 3.42 ± 0.80, 3.94 ± 1.81, 4.20 ± 1.07; p = 0.038), total testosterone (TT) (16.6 ± 6.1, 15.2 ± 5.3, 11.3 ± 4.44 nmol/l; p < 0.001) and free testosterone (FT) levels (440.4 ± 160.8, 389.6 ± 162.5, 294.5 ± 107.0 pmol/l; p < 0.001). TT level was in a significant negative correlation with AHI, oxygen desaturation index (ODI), BMI, MetS and siMS. Also, FT was in a significant negative correlation with AHI, ODI, BMI, age, MetS and siMS. The multiple regression analysis revealed that both AHI and ODI were in significant correlation with TT and FT after adjustment for age, BMI, siMS score and MetS components.

Conclusion

Obstructive sleep apnea is associated with low TT and FT levels in severely obese men.

Premature ejaculation in OSAS: Does it improve with CPAP treatment?

AIM

Premature ejaculation (PE) is a common problem in male sexual health that significantly affects the quality of life. We aimed to evaluate the association of PE with obstructive sleep apnoea syndrome (OSAS), which is characterised by chronic oxidative stress, and to assess the effects of continuous positive airway pressure (CPAP) therapy on PE.

MATERIAL AND METHODS

Sexually active men between the ages of 20 and 50 who were newly diagnosed with PE, and diagnosed with moderate or severe OSAS were included in the study. Arabic Premature Ejaculation Index (AIPE) and Intravaginal Ejection Delay Time (IELT) were questioned for the diagnosis of PE. Patients with OSAS who accepted to participate in the study were given 1 year of CPAP treatment, and AIPE and IELT were questioned again, after the treatment. The results are compared with the results of the control group.

RESULTS

In total, 80 control subjects without OSAS, 85 patients with moderate OSAS and 82 patients with severe OSAS were included in the study. There were no significant differences between the groups in terms of age, BMI or thyroid function test results. Initial IELT and AIPE scores were significantly higher in the control group compared with the OSAS groups (for the IELT, 155.63 ± 98.78 vs 96.23 ± 60.60 and 62.86 ± 40.49; for the AIPE 26.18 ± 3.88 vs 18.71 ± 3.43 and 17.85 ± 3.83). Compared with initial (pretreatment) values, both scores improved significantly in both OSAS groups after 1 year of CPAP therapy (in moderate OSAS group, 96.23 ± 60.60 vs 134.17 ± 83.43 and 18.71 ± 3.43 vs 23.25 ± 3.43 and severe OSAS group 62.86 ± 40.49 vs 112.25 ± 71.58 and 17.85 ± 3.83 vs 24.18 ± 3.53).

CONCLUSION

For the first time in literature, we determined that the presence of OSAS was associated with significantly worse IELT and AIPE scores in males with PE, and the treatment of OSAS was related to the significant improvements in both scores, in the absence of any specific treatments for PE.

Exosomes derived from miR-301a-3p-overexpressing adipose-derived mesenchymal stem cells reverse hypoxia-induced erectile dysfunction in rat models

Background

Erectile dysfunction (ED) has often been observed in patients with obstructive sleep apnea (OSA). Research on adipose-derived mesenchymal stem cell (ADSC)-derived exosomes has shown that they have significant therapeutic effects in many diseases including ED.

Methods

In this study, ED was induced in Sprague Dawley (SD) rats using chronic intermittent hypoxia (CIH) exposure. CIH-mediated influences were then measured in the corpus cavernous smooth muscle cells (CCSMCs).

Results

Our data showed that miR-301a-3p-enriched exosome treatment significantly recovered erectile function in rats and CCSMCs by promoting autophagy and inhibiting apoptosis. The treatment also significantly recovered the level of alpha smooth muscle actin (α-SMA) in rats and CCSMCs. Bioinformatics predicted that phosphatase and tensin homolog (PTEN) and Toll-like receptor 4 (TLR4) might be targets of miR-301a-3p.

Conclusions

Our results indicate that PTEN-overexpression vectors or TLR4-overexpression vectors reverse the therapeutic effects achieved by miR-301a-3p in CCSMCs indicating that PTEN/hypoxia-inducible factor-1 alpha (HIF-1α) and TLR4 signaling pathways play key roles in the progression of ED. The findings in this study suggest that miR-301a-3p should be considered a new therapeutic target for treating ED associated with OSA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02161-8.

The dorsal and the ventral side of hypoglossal motor nucleus showed different response to chronic intermittent hypoxia in rats

PURPOSE

To study neurochemical reactions to chronic intermittent hypoxia (CIH) in the hypoglossal nucleus (HN) of rats.

METHODS

Adult male Sprague-Dawley rats (n = 12) were randomly divided into two groups (the CIH and the control group). The CIH rats were housed in a hypoxic chamber with the fraction of oxygen volume alternating between 21% and 5% by providing air for 60 s and then providing nitrogen for 60 s from 8:30 am to 16:30 pm each day for 35 days. The control group was housed in a cabin with normal oxygen levels. We studied the expression of c-fos protein, 5-hydroxytryptamine (5-HT) positive terminals, and its 2A receptors in hypoglossal nuclei by immunohistochemistry.

RESULTS

The expression of c-fos, 5-HT positive terminals, and accordingly 5-HT 2A receptors in the CIH group were significantly higher than that in the controls (p < 0.05). The ventral side of the HN showed a clearly higher expression of 5-HT and its 2A receptors than the dorsal side (p < 0.05).

CONCLUSION

There were 2 responses of the HN to CIH. First, CIH induced a higher expression of 5-HT positive terminals and its 2A receptors, and second, this reaction was much more evident in ventral side than in the dorsal side. We postulate that these responses may serve to be a protective and compensatory mechanism for CIH.

Blood Oxygen Accumulation Distribution Area Index Is Associated With Erectile Dysfunction in Patients With Sleep Apnea-Results From a Cross-sectional Study

Introduction

Obstructive sleep apnea (OSA) has been linked with erectile dysfunction (ED), but the relatively independent polysomnography (PSG) outcomes of apnea and nocturnal hypoxia may not effectively assess the physiological impairment of OSA well.

Aim

To propose a new calculation method, the blood oxygen accumulation distribution area index (BOADAI), for evaluating the association between OSA and ED.

Methods

In this study, 502 male participants with suspected OSA were enrolled. Clinical questionnaire, physical measurements, and PSG outcomes were obtained by 2 respiratory physicians. ED was assessed by a urologist using the International Index of Erectile Function-5 (IIEF-5). Whole pulse oxygen saturation curves during the sleep time were compressed into a fixed scale image, and the distribution area of oxygen saturation curves was outlined. We then calculated the value of the outlined area and normalized it by total sleep time. The least absolute shrinkage and selection operator logistic regression model was used for selecting the optimal variable associated with ED and model construction. The clinical net benefit of the BOADAI and its related modules was estimated and compared by decision curve analysis.

Main Outcome Measure

ED and OSA were assessed using the IIEF-5, clinical questionnaire, physical measurements, and PSG outcomes.

Results

The frequency of ED in patients with OSA was significantly greater than that in the no-OSA group. Meanwhile, the new BOADAI was negatively correlated with the IIEF-5 score (r = −0.2525, P = .0000). Moreover, the least absolute shrinkage and selection operator method retained BOADAI but not the other PSG parameters such as respiratory disorder index and lowest SaO2. Finally, logistic regression analysis revealed that older age, lips with cyanochroia, systemic hypertension, and BOADAI were independently associated with ED, and decision curve analysis indicated the clinical usefulness of the BOADAI module.

Conclusion

This study revealed novel evidence that OSA is a risk factor for ED. Meanwhile, the BOADAI could act as a potential clinical characteristic to evaluate ED in patients with OSA and to provide clinical treatment recommendations.

Zheng W, Chen X, Huang J, et al. Blood Oxygen Accumulation Distribution Area Index Is Associated With Erectile Dysfunction in Patients With Sleep Apnea—Results From a Cross-sectional Study. Sex Med 2019; 8:36–44.

Beneficial effects of estrogens in obstructive sleep apnea hypopnea syndrome

Epidemiological studies showing the higher frequency of obstructive sleep apnea hypopnea syndrome in men, polycystic ovary syndrome (PCOS), and in post-menopausal women suggest the beneficial role of estrogen. These findings are well supported by the pre-clinical studies (ten research studies described in this review) showing that estrogen and phytoestrogens attenuate the deleterious effects of chronic intermittent hypoxia (obstructive apnea in animals) on the genioglossal muscles and on other organs (co-morbidities) in ovariectomized rodents. Moreover, clinical studies (four research studies described in this review) have also shown the beneficial role of estrogen therapy on the parameters of obstructive apnea in post-menopausal women. The beneficial effects of estrogen and phytoestrogens on obstructive sleep apnea and its co morbidities have been attributed to increase in thioredoxin, Nrf-2, activation of p38 MAP kinases, inhibition of vagal C fibers, and attenuation of HIF-1α. It is possible that estrogen-mediated activation of p38 MAP kinase may inhibit HIF-1α to attenuate lung inflammation, which may inhibit the activation of vagal C fibers to attenuate bronchoconstriction and prevent obstruction during sleep. Moreover, estrogen-mediated increase in thioredoxin and Nrf-2 may also contribute in increasing antioxidant defense and attenuating inflammation.

Obstructive Sleep Apnea and Testosterone Deficiency

Obstructive sleep apnea (OSA) is a common disorder characterized by intermittent hypoxia and sleep fragmentation. OSA in middle-aged men is often associated with decreased testosterone secretion, together with obesity and aging. Although OSA treatment does not reliably increase testosterone levels in most studies, OSA treatment with testosterone replacement therapy (TRT) may not only improve hypogonadism, but can also alleviate erectile/sexual dysfunction. However, because TRT may exacerbate OSA in some patients, patients should be asked about OSA symptoms before and after starting TRT. Furthermore, TRT should probably be avoided in patients with severe untreated OSA.

Chronic intermittent hypoxia induces hormonal and male sexual behavioral changes: Hypoxia as an advancer of aging

Sleep apnea is a common sleep disorder characterized by intermittent periods of low blood oxygen levels. The risk for sleep apnea increases with age and is more prevalent in men than women. A common comorbidity of sleep apnea includes male sexual dysfunction, but it is not clear if a causal relationship exists between sleep apnea and sexual dysfunction. Possible mechanisms that link these two disorders include oxidative stress and testosterone. Oxidative stress is elevated in clinical patients with sleep apnea and in rodents exposed to chronic intermittent hypoxia (CIH), an animal model for apnea-induced hypopnea. Further, oxidative stress levels increase with age. Therefore, age may play a role in sleep apnea-induced sexual dysfunction and oxidative stress generation. To investigate this relationship, we exposed gonadally intact 3 (young) and 12 (middle-aged) month old male F344/BN F1 hybrid male rats to 8 days of CIH, and then examined male sexual function. Plasma was used to assess circulating oxidative stress and hormone levels. Middle-aged male rats had lower testosterone levels with increased sexual dysfunction and oxidative stress, independent of CIH. However, CIH decreased testosterone levels and increased sexual dysfunction and oxidative stress only in young gonadally intact male rats, but not in gonadectomized young rats with physiological testosterone replacement. In sum, CIH had a greater impact on younger gonadally intact animals, with respect to sexual behaviors, testosterone, and oxidative stress. Our data indicate CIH mimics the effects of aging on male sexual behavior in young gonadally intact male rats.

Effects of obstructive sleep apnea and its treatment over the erectile function: a systematic review

Erectile dysfunction (ED) is considered a condition with a broad range of etiologies. Obstructive sleep apnea (OSA) syndrome is one of the lesser studied risk factors for ED. We intend to summarize the current evidence on the relationship between OSA and sexual impairment, focusing on the results in terms of erectile function of the different therapies offered to OSA patients. A systematic review was conducted, selecting articles related to the physiology of OSA and ED, and to the treatments of OSA syndrome and their reported outcomes in erectile and sexual function. Higher prevalences of ED in the OSA groups have been published. However, whether this effect on the erectile function occurs in the entire range of OSA severities remains unclear. Several hypotheses were proposed to explain the physiology of this association. Continuous Positive Airway Pressure as a treatment for OSA patients with ED has achieved a significative improvement in the sexual parameters in most of the studies. Phosphodiesterase type 5 inhibitors (iPDE5) on demand are useful as a treatment for ED in this subgroup of patients, with high satisfaction rates. The surgical treatment for the OSA evidenced benefits over the erectile function, and the effect on the sexual satisfaction of the therapy using Mandibular Advancement Devices is still undefined.

Sleep-disordered breathing in patients with sickle cell disease

Sickle cell disease is one of the most common hereditary hemoglobinopathies worldwide, and its vaso-occlusive and hemolytic crises cause considerable patient morbidity. A growing body of evidence has shown that sleep-disordered breathing, and in particular, obstructive sleep apnea, occurs at high frequency in the sickle cell population, and that there is significant overlap in the underlying pathophysiology of these two conditions. Through a variety of mechanisms including nocturnal hypoxemia and increased oxidative stress, production of pro-inflammatory cytokines, and endothelial dysfunction, sickle cell anemia and sleep-disordered breathing potentiate each other's clinical effects and end-organ complications. Here, we will review the shared pathophysiologic mechanisms of these conditions and discuss their clinical sequelae. We will also examine the results of studies that have been carried out with clinical intervention of nocturnal hypoxemia in patients with sickle cell disease in the attempts to overcome the complications of the disease. Finally, we will propose the areas of investigation that merit further investigations in future in patients with sickle cell disease and sleep-disordered breathing.

Sleep disorders in patients with erectile dysfunction

OBJECTIVE

To assess the prevalence of obstructive sleep apnoea (OSA) in men presenting with erectile dysfunction (ED) at a single centre.

PATIENTS AND METHODS

All men attending a specialised andrology outpatient department with a new diagnosis of ED were included in this prospective study. All patients completed three questionnaires: the International Index of Erectile Function (IIEF) and two sleep questionnaires [the Obstructive Sleep Apnoea Screening questionnaire and the Insomnia Severity Index (ISI)]. Their ED management was subsequently undertaken in accordance with local and European guidelines. An OSA diagnosis was made based on a score of ≥3 on the Obstructive Sleep Apnoea Screening questionnaire and those patients were referred for specialist management.

RESULTS

Between February and September 2016, 129 patients with ED completed the study questionnaires. In all, 71 patients (55%) had a score of ≥3 on the Obstructive Sleep Apnoea Screening questionnaire, indicating a need for specialist sleep referral. Men who scored ≥3 on the Obstructive Sleep Apnoea Screening questionnaire were significantly older (61.4 vs 46.5 years; P < 0.001) and had a significantly higher body mass index (29.4 vs 26.7 kg/m² ; P < 0.001) when compared to the control group (OSA score of <3). The sleep apnoea group (OSA score of ≥3) had significantly worse IIEF-ED scores (6.2 vs 9.1; P = 0.018) and ISI scores (7.9 vs 5.5; P = 0.061).

CONCLUSION

Men presenting to the andrology clinic with ED are at significant risk of having undiagnosed sleep disorders. This has serious adverse health consequences, as well as being associated with potential dangers at work and travel. The patient compliance was high with 78% completing all three questionnaires. It is feasible to screen this population for sleep disturbance and this should be part of the ED assessment.

Prolonged Exposures to Intermittent Hypoxia Promote Visceral White Adipose Tissue Inflammation in a Murine Model of Severe Sleep Apnea: Effect of Normoxic Recovery

Study Objective

Increased visceral white adipose tissue (vWAT) mass results in infiltration of inflammatory macrophages that drive inflammation and insulin resistance. Patients with obstructive sleep apnea (OSA) suffer from increased prevalence of obesity, insulin resistance, and metabolic syndrome. Murine models of intermittent hypoxia (IH) mimicking moderate-severe OSA manifest insulin resistance following short-term IH. We examined in mice the effect of long-term IH on the inflammatory cellular changes within vWAT and the potential effect of normoxic recovery (IH-R).

Methods

Male C57BL/6J mice were subjected to IH for 20 weeks, and a subset was allowed to recover in room air (RA) for 6 or 12 weeks (IH-R). Stromal vascular fraction was isolated from epididymal vWAT and mesenteric vWAT depots, and single-cell suspensions were prepared for flow cytometry analyses, reactive oxygen species (ROS), and metabolic assays.

Results

IH reduced body weight and vWAT mass and IH-R resulted in catch-up weight and vWAT mass. IH-exposed vWAT exhibited increased macrophage counts (ATMs) that were only partially improved in IH-R. IH also caused a proinflammatory shift in ATMs (increased Ly6c(hi)(+) and CD36(+) ATMs). These changes were accompanied by increased vWAT insulin resistance with only partial improvements in IH-R. In addition, ATMs exhibited increased ROS production, altered metabolism, and changes in electron transport chain, which were only partially improved in IH-R.

Conclusion

Prolonged exposures to IH during the sleep period induce pronounced vWAT inflammation and insulin resistance despite concomitant vWAT mass reductions. These changes are only partially reversible after 3 months of normoxic recovery. Thus, long-lasting OSA may preclude complete reversibility of metabolic changes.

Intermittent hypoxia causes NOX2-dependent remodeling of atrial connexins

BACKGROUND

Obstructive sleep apnea has been linked to the development of heart disease and arrhythmias, including atrial fibrillation. Since altered conduction through gap junction channels can contribute to the pathogenesis of such arrhythmias, we examined the abundance and distributions of the major cardiac gap junction proteins, connexin40 (Cx40) and connexin43 (Cx43) in mice treated with sleep fragmentation or intermittent hypoxia (IH) as animal models of the components of obstructive sleep apnea.

RESULTS

Wild type C57BL/6 mice or mice lacking NADPH 2 (NOX2) oxidase activity (gp91phox(-/Y)) were exposed to room air or to SF or IH for 6 weeks. Then, the mice were sacrificed, and atria and ventricles were immediately dissected. The abundances of Cx40 or Cx43 in atria and ventricles were unaffected by SF. In contrast, immunoblots showed that the abundance of atrial Cx40 and Cx43 and ventricular Cx43 were reduced in mice exposed to IH. qRT-PCR demonstrated significant reductions of atrial Cx40 and Cx43 mRNAs. Immunofluorescence microscopy revealed that the abundance and size of gap junctions containing Cx40 or Cx43 were reduced in atria by IH treatment of mice. However, no changes of connexin abundance or gap junction size/abundance were observed in IH-treated NOX2-null mice.

CONCLUSIONS

These results demonstrate that intermittent hypoxia (but not sleep fragmentation) causes reductions and remodeling of atrial Cx40 and Cx43. These alterations may contribute to the substrate for atrial fibrillation that develops in response to obstructive sleep apnea. Moreover, these connexin changes are likely generated in response to reactive oxygen species generated by NOX2.

Efficacy of nasal continuous positive airway pressure on patients with OSA with erectile dysfunction and low sex hormone levels

PURPOSE

This study aimed to test the hypothesis that erectile dysfunction (ED) is common in men with obstructive sleep apnea (OSA). We also assessed the efficacy of continuous positive airway pressure (CPAP) treatment for ED and sex hormone levels in patients with severe OSA and ED.

METHODS

A total of 153 OSA patients and 60 healthy controls were enrolled in this study. The International Index of Erectile Dysfunction-5 (IIEF-5) score was obtained, and blood samples were collected for analysis of sex hormones after polysomnography. The IIEF-5 score, sex hormone levels, and polysomnographic parameters were re-evaluated in 32 patients with severe OSA and ED after 1 month of CPAP treatment.

RESULTS

The present study showed that the prevalence of ED was 47.1% in all cases and only 13.3% in controls, and a lower sex hormone levels was presented in OSA patients. OSA patients with ED had greater severity of disease, and lower serum levels of follicle stimulating hormone (FSH) and testosterone than OSA patients without ED (p < 0.05). After CPAP therapy, there was a significant increase in the IIEF-5 score, and serum levels of FSH, luteinizing hormone, and testosterone, were elevated compared with baseline levels (p < 0.05). Multivariate regression analysis indicated the serum level of testosterone had impact on the ED.

CONCLUSIONS

OSA patients had lower sex hormone levels and a higher occurrence of ED than controls, and serum level of testosterone had effect on ED. CPAP treatment ameliorated the symptoms of ED and elevated serum levels of FSH, luteinizing hormone, and testosterone.

Erectile Dysfunction and Sexual Hormone Levels in Men With Obstructive Sleep Apnea: Efficacy of Continuous Positive Airway Pressure

In this study, the prevalence of erectile dysfunction (ED) and serum sexual hormone levels were evaluated in men with obstructive sleep apnea (OSA). In these patients, the efficacy of continuous positive airway pressure (CPAP) was determined. The 207 men (mean age 44.0 ± 11.1 years) enrolled in the study were stratified within four groups based on their apnea-hypopnea index score: simple snoring (n = 32), mild OSA (n = 29), moderate OSA (n = 38), and severe OSA (n = 108). The International Index of Erectile Dysfunction-5 (IIEF-5) score was obtained from each patient, and blood samples for the analysis of sexual hormones (prolactin, luteotropin, follicle-stimulating hormone, estradiol, progestin, and testosterone) were drawn in the morning after polysomnography. The IIEF-5 test and serum sexual hormone measurements were repeated after 3 months of CPAP treatment in 53 men with severe OSA. The prevalence of ED was 60.6 % in OSA patients overall and 72.2 % in those with severe OSA. Compared with the simple snoring group, patients with severe OSA had significantly lower testosterone levels (14.06 ± 5.62 vs. 17.02 ± 4.68, p = .018) and lower IIEF-5 scores (16.33 ± 6.50 vs. 24.09 ± 1.94, p = .001). The differences in the other sexual hormones between groups were not significant. After 3 months of CPAP treatment, there were no significant changes in sexual hormone levels, but the IIEF-5 score had improved significantly (18.21 ± 4.05 vs. 19.21 ± 3.86, p = .001). Severe OSA patients have low testosterone concentration and high ED prevalence. IIEF-5 scores increased significantly after CPAP treatment, but there was no effect on serum testosterone levels.

Erectile Dysfunction in Patients with Sleep Apnea--A Nationwide Population-Based Study

Increased incidence of erectile dysfunction (ED) has been reported among patients with sleep apnea (SA). However, this association has not been confirmed in a large-scale study. We therefore performed a population-based cohort study using Taiwan National Health Insurance (NHI) database to investigate the association of SA and ED. From the database of one million representative subjects randomly sampled from individuals enrolled in the NHI system in 2010, we identified adult patients having SA and excluded those having a diagnosis of ED prior to SA. From these suspected SA patients, those having SA diagnosis after polysomnography were defined as probable SA patients. The dates of their first SA diagnosis were defined as their index dates. Each SA patient was matched to 30 randomly-selected, age-matched control subjects without any SA diagnosis. The control subjects were assigned index dates as their corresponding SA patients, and were ensured having no ED diagnosis prior to their index dates. Totally, 4,835 male patients with suspected SA (including 1,946 probable SA patients) were matched to 145,050 control subjects (including 58,380 subjects matched to probable SA patients). The incidence rate of ED was significantly higher in probable SA patients as compared with the corresponding control subjects (5.7 vs. 2.3 per 1000 patient-year; adjusted incidence rate ratio = 2.0 [95% CI: 1.8-2.2], p<0.0001). The cumulative incidence was also significantly higher in the probable SA patients (p<0.0001). In multivariable Cox regression analysis, probable SA remained a significant risk factor for the development of ED after adjusting for age, residency, income level and comorbidities (hazard ratio = 2.0 [95%CI: 1.5-2.7], p<0.0001). In line with previous studies, this population-based large-scale study confirmed an increased ED incidence in SA patients in Chinese population. Physicians need to pay attention to the possible underlying SA while treating ED patients.

Adipose tissue macrophage polarization by intermittent hypoxia in a mouse model of OSA: effect of tumor microenvironment

Intermittent hypoxia (IH)-induces alterations in tumor-associated macrophages (TAMs) that are associated with adverse cancer outcomes, as reported in patients suffering from sleep apnea. Adipose tissues (AT) and bone-marrow (BM)-derived cells are the inferred sources of macrophages infiltrating malignant tumors. Here, the sources of TAMs and the phenotypic changes induced by IH in the ipsilateral and contralateral AT were investigated by using a syngeneic murine solid tumor model (TC1). C57/B6 male mice were exposed to either IH or room air (RA) for 6 weeks, with TC1 cells being inoculated in the 2nd week. Macrophage content, phenotype and tissue origin were assessed in tumors, and ipsilateral and contralateral AT. IH induced a ~2.2-fold increase in TAM tumor infiltration. However, differential responses in the tumor ipsilateral and contralateral AT emerged: IH increased infiltration of preferentially M1 macrophages in contralateral AT, while reductions in macrophages emerged in ipsilateral AT and primarily consisted of the M2 phenotype. These changes were accompanied by reciprocal increases in resident and BM-derived TAMs in the tumor. IH-induced phenotypic alterations in AT macrophages surrounding the tumor and their increased infiltration within the tumor may contribute to the accelerated tumor progression associated with IH.

Hemoglobinopathies and sleep--The road less traveled

Sickle cell disease and thalassemia are common hereditary blood disorders associated with increased systemic inflammation, tissue hypoxia, endothelial dysfunction and end-organ damage, the latter accounting for the substantial morbidity and abbreviated lifespan associated with these conditions. Sleep perturbations in general, and sleep-disordered breathing in particular are also highly prevalent conditions and the mechanisms underlying their widespread end-organ morbidities markedly and intriguingly overlap with the very same pathways implicated in the hemoglobinopathies. However, little attention has been given to date to the potential contributing role of sleep disorders to sickle cell disease manifestations. Here, we comprehensively review the pathophysiological mechanisms and clinical manifestations linking disturbed sleep and hemoglobinopathies, with special emphasis on sickle cell disease. In addition to a broad summary of the available evidence, we identify many of the research gaps that require attention and future investigation, and provide the scientific contextual setting that should enable opportunities to investigate the intertwined pathophysiological mechanisms and clinical outcomes of sleep disorders and hemoglobinopathies.

The relationship between sleep disorders and testosterone in men

Plasma testosterone levels display circadian variation, peaking during sleep, and reaching a nadir in the late afternoon, with a superimposed ultradian rhythm with pulses every 90 min reflecting the underlying rhythm of pulsatile luteinizing hormone (LH) secretion. The increase in testosterone is sleep, rather than circadian rhythm, dependent and requires at least 3 h of sleep with a normal architecture. Various disorders of sleep including abnormalities of sleep quality, duration, circadian rhythm disruption, and sleep-disordered breathing may result in a reduction in testosterone levels. The evidence, to support a direct effect of sleep restriction or circadian rhythm disruption on testosterone independent of an effect on sex hormone binding globulin (SHBG), or the presence of comorbid conditions, is equivocal and on balance seems tenuous. Obstructive sleep apnea (OSA) appears to have no direct effect on testosterone, after adjusting for age and obesity. However, a possible indirect causal process may exist mediated by the effect of OSA on obesity. Treatment of moderate to severe OSA with continuous positive airway pressure (CPAP) does not reliably increase testosterone levels in most studies. In contrast, a reduction in weight does so predictably and linearly in proportion to the amount of weight lost. Apart from a very transient deleterious effect, testosterone treatment does not adversely affect OSA. The data on the effect of sleep quality on testosterone may depend on whether testosterone is given as replacement, in supratherapeutic doses, or in the context abuse. Experimental data suggest that testosterone may modulate individual vulnerability to subjective symptoms of sleep restriction. Low testosterone may affect overall sleep quality which is improved by replacement doses. Large doses of exogenous testosterone and anabolic/androgenic steroid abuse are associated with abnormalities of sleep duration and architecture.

Male fertility is reduced by chronic intermittent hypoxia mimicking sleep apnea in mice

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia and oxidative stress. However, it is unknown whether intermittent hypoxia mimicking OSA modifies male fertility. We tested the hypothesis that male fertility is reduced by chronic intermittent hypoxia mimicking OSA in a mouse model.

DESIGN

Case-control comparison in a murine model.

SETTING

University research laboratory.

PARTICIPANTS

Eighteen F1 (C57BL/6xCBA) male mice.

INTERVENTIONS

Mice were subjected to a pattern of periodic hypoxia (20 sec at 5% O2 followed by 40 sec of room air) 6 h/day for 60 days or normoxia. After this period, mice performed a mating trial to determine effective fertility by assessing the number of pregnant females and fetuses.

MEASUREMENTS AND RESULTS

After euthanasia, oxidative stress in testes was assessed by measuring the expression of glutathione peroxidase 1 (Gpx1) and superoxide dismutase-1 (Sod1) by reverse-transcription polymerase chain reaction. Sperm motility was determined by Integrated Semen Analysis System (ISAS). Intermittent hypoxia significantly increased testicular oxidative stress, showing a reduction in the expression of Gpx1 and Sod1 by 38.9% and 34.4%, respectively, as compared with normoxia (P < 0.05). Progressive sperm motility was significantly reduced from 27.0 ± 6.4% in normoxia to 12.8 ± 1.8% in the intermittent hypoxia group (P = 0.04). The proportion of pregnant females and number of fetuses per mating was significantly lower in the intermittent hypoxia group (0.33 ± 0.10 and 2.45 ± 0.73, respectively) than in normoxic controls (0.72 ± 0.16 and 5.80 ± 1.24, respectively).

CONCLUSIONS

These results suggest that the intermittent hypoxia associated with obstructive sleep apnea (OSA) could induce fertility reduction in male patients with this sleep breathing disorder.

Testosterone and estradiol are not affected in male and female patients with obstructive sleep apnea treated with continuous positive airway pressure

BACKGROUND

Continuous positive airway pressure (CPAP) improves symptoms in patients with obstructive sleep apnea syndrome (OSAS). It is currently unclear, whether CPAP also alters endocrine parameters such as sex hormone levels. In a previous study, we have found no changes in sex hormones in patients with OSAS after one night with CPAP.

AIM

The aim of this study was to prove long-term effects of CPAP on sex hormone concentrations in patients with OSAS.

METHODS

Twenty-two women and 67 men with severe OSAS (respiratory distress index > 30/h) were enrolled in the study. Fasting blood venous samples were taken before CPAP therapy and after 1 and 6 months of CPAP treatment. Testosterone and estradiol were measured in all samples using commercially available ELISA kits.

RESULTS

No effects of long-term CPAP treatment were found on testosterone or estradiol levels in OSAS patients of either gender.

CONCLUSIONS

The results are in line with previous smaller studies. However, our study is larger and longer than previously published studies. In addition, this is the first study analyzing the effects of CPAP on testosterone and estradiol and in both genders. Positive effects of CPAP on sexual functions reported in other studies might, thus, be mediated by other than endocrine effects.

Long-term changes of sexual function in men with obstructive sleep apnea after initiation of continuous positive airway pressure

INTRODUCTION

Obstructive sleep apnea (OSA), particularly intermittent nocturnal hypoxemia, is associated with erectile dysfunction (ED).

AIM

We investigated in patients with OSA whether continuous positive airway pressure (CPAP) therapy has a long-term effect on sexual function, including ED, in the presence of other risk factors for ED.

METHODS

Within a long-term observational design, we reassessed 401 male patients who had been referred for polysomnography, with respect to erectile and overall sexual function. Mean ± standard deviation follow-up time was 36.5 ± 3.7 months. Patients with moderate to severe ED were stratified according to the regular use of CPAP.

MAIN OUTCOME MEASURE

Changes of sexual function were assessed by the 15-item International Index of Erectile Function (IIEF-15) questionnaire, including the domains erectile function (EF), intercourse satisfaction, orgasmic function (OF), sexual desire (SD), and overall satisfaction (OS).

RESULTS

Of the 401 patients, 91 returned a valid IIEF-15 questionnaire at follow-up. Their baseline characteristics were not different from those of the total study group. OSA (apnea-hypopnea index >5/hour) had been diagnosed in 91.2% of patients. In patients with moderate to severe ED (EF domain <17), CPAP users (N = 21) experienced an improvement in overall sexual function (IIEF-15 summary score; P = 0.014) compared with CPAP non-users (N = 18), as well as in the subdomains OF (P = 0.012), SD (P = 0.007), and OS (P = 0.033). Similar results were obtained in patients with poor overall sexual dysfunction (IIEF-15 summary score <44). In patients with moderate to severe ED and low mean nocturnal oxygen saturation (≤93%, median), also the EF subdomain improved in CPAP users vs. non-users (P = 0.047).

CONCLUSIONS

These data indicate that long-term CPAP treatment of OSA and the related intermittent hypoxia can improve or preserve sexual function in men with OSA and moderate to severe erectile or sexual dysfunction, suggesting a certain reversibility of OSA-induced sexual dysfunctions.

Erectile dysfunction in obstructive sleep apnea syndrome--prevalence and determinants

INTRODUCTION

OSAS (Obstructive Sleep apnea syndrome) is defined by recurrent episodes of upper airway obstruction during sleep, causing multiple clinical consequences. Literature review suggests that OSAS induces a spectrum of abnormalities in neural, hormonal and vascular regulation that contribute to the development of ED (erectile dysfunction). The aims of this study were to estimate the prevalence of ED in OSAS patients and evaluate its determinants.

METHODS

62 patients from Hospital S. João Sleep Laboratory with newly diagnosed OSAS were included in the study and answered the IIEF-5 (international index erectile function 5 item version) questionnaire.

RESULTS

The prevalence of ED in OSAS patients was 64.4%. Age and Diabetes constituted themselves as independent risk factors for more severe degrees of ED: OR=1.226 (95%CI: 1.062-1.415) and OR=31.205 (95%CI: 1.222-796.557), respectively. Compared with nonsmokers, ex-smokers group revealed a positive association with ED: OR=4.32 (95%CI: 1.09-17.11). Hypertension and ACEI (angiotensin converting enzyme inhibitors) or ARB (angiotensin II receptor blockers) therapy were also correlated to ED symptoms: OR=3.25 (95%CI: 1.09-9.65) and 7.39 (95%CI: 1.52-35.99), respectively. No association was found relating BMI (p=0.254), alcoholic habits (p=0.357), acute myocardial infarction (p=0.315), dyslipidemia (p=0.239),metabolic syndrome (p=0.215) and ED. OSAS severity was not associated with ED in our sample.

CONCLUSIONS

The prevalence of ED in OSAS patients is high. ED determinants in our sample were age and diabetes. Past smoking habits, hypertension and ACEI/ARB therapy also revealed a statistically significant association with ED.

Effects of hypoxia on nocturnal erection quality: a case report from the Manaslu expedition

INTRODUCTION

High altitude environment represents a fine model to study physiological and pathophysiological effects of oxygen availability on sleep-related erections (SREs).

AIM

To describe altitude-dependent effects on quality of SREs in order to estimate the role of hypoxia in erection physiology.

METHODS

A healthy 37-year-old male mountain climber underwent a chronic high altitude-related hypoxia experience during the 43 days of the Manaslu expedition (Nepal). SREs were recorded by RigiScan (Timm Medical Technologies, Inc., Eden Prairie, MN, USA) at altitudes ranging from 0 to 5,800 m above sea level. The erection-related parameters assessed were: number, duration, event duration (% of session), event rigidity %, time rigidity %, tumescence and rigidity activated unit, and event tum % > bline (%).

MAIN OUTCOMES MEASURES

SREs were recorded by RigiScan at altitudes ranging from 0 to 5,800 m above sea level.

RESULTS

Erectile parameters showed an altitude-related reduction during the hypoxic exposure, although all functional alterations were reverted by the return to sea level.

CONCLUSIONS

Our case report supports the hypothesis that oxygen availability and delivery could play an important role in the regulation of local penile erection-related mechanisms and that low oxygen levels might be considered an etiological cofactor in erectile dysfunction.

Chronic intermittent hypoxia induces lung growth in adult mice

Obstructive sleep apnea (OSA) increases cardiovascular morbidity and mortality, which have been attributed to intermittent hypoxia (IH). The effects of IH on lung structure and function are unknown. We used a mouse model of chronic IH, which mimics the O(2) profile in patients with OSA. We exposed adult C57BL/6J mice to 3 mo of IH with a fraction of inspired oxygen (F(I)(O(2))) nadir of 5% 60 times/h during the 12-h light phase. Control mice were exposed to room air. Lung volumes were measured by quasistatic pressure-volume (PV) curves under anesthesia and by water displacement postmortem. Lungs were processed for morphometry, and the mean airspace chord length (Lm) and alveolar surface area were determined. Lung tissue was stained for markers of proliferation (proliferating cell nuclear antigen), apoptosis (terminal deoxynucleotidyl transferase dUTP nick-end labeling), and type II alveolar epithelial cells (surfactant protein C). Gene microarrays were performed, and results were validated by real-time PCR. IH increased lung volumes by both PV curves (air vs. IH, 1.16 vs. 1.44 ml, P < 0.0001) and water displacement (P < 0.01) without changes in Lm, suggesting that IH increased the alveolar surface area. IH induced a 60% increase in cellular proliferation, but the number of proliferating type II alveolocytes tripled. There was no increase in apoptosis. IH upregulated pathways of cellular movement and cellular growth and development, including key developmental genes vascular endothelial growth factor A and platelet-derived growth factor B. We conclude that IH increases alveolar surface area by stimulating lung growth in adult mice.

Outcome of CPAP treatment on intimate and sexual relationships in men with obstructive sleep apnea

STUDY OBJECTIVES

To examine intimate and sexual relationships in patients with obstructive sleep apnea (OSA), the association with daytime sleepiness, and the change in these outcomes with continuous positive airway pressure treatment (CPAP).

DESIGN

Pre-post test, quasi-experimental study.

SETTING

Seven sleep disorders centers in the U.S. and Canada.

PARTICIPANTS

123 males with OSA (AHI > or =20), aged 21 to 60 years.

INTERVENTIONS

Nasal CPAP for > or =3 months.

MEASUREMENTS AND RESULTS

Compared to normal values, at baseline patients were significantly sleepier, as measured by the Multiple Sleep Latency Test and Epworth Sleepiness Scale. They were also more impaired in intimate and sexual relationships, as measured by the Intimate and Sexual Relationships subscale of the Functional Outcomes of Sleep Questionnaire. Neither race nor marital status was significantly associated with impaired intimate and sexual relationships. Following treatment, patients were significantly more alert and had reported improved intimate and sexual relationships, with the greatest change occurring in those with the most disease severity.

CONCLUSIONS

OSA has an adverse impact on intimate and sexual relationships that is related to subjective sleepiness and improved with CPAP treatment.

Prevalence of erectile dysfunction complaints associated with sleep disturbances in Sao Paulo, Brazil: a population-based survey

INTRODUCTION

The aims of this study were to estimate the prevalence of erectile dysfunction (ED) complaints in a population-based sample from Sao Paulo and to determine the associations of ED prevalence with sleep disturbances, testosterone levels, age, body mass index (BMI), socioeconomic factors and selected medical history indicators.

METHODS

The Epidemiologic Sleep Study (EPISONO) is a population-based study of sleep and risk factors for sleep disturbances in Brazil's largest city, Sao Paolo. This study adopted a probabilistic three-stage cluster sampling approach for the city of Sao Paulo. Questionnaires that covered medical conditions and sexual and erection complaints were administered and polysomnographies and fasting blood samples were collected. The patient cohort of the current study of ED consisted of 467 men, aged 20-80 years at the time of their enrollment in EPISONO. The percentage of men who participated in EPISONO but refused to participate in our study was 2.3%.

RESULTS

The prevalence of ED complaints in the study cohort was 17.08% overall. ED complaints ranged from 7.3% in younger men (20-29 years old) to 63.25% in older men (>50years old) (adjusted odds ratio [OR]=21.65). The logistic regression model showed that both reduced time spent in REM sleep and fragmented sleep had significant effects as risk factors for ED complaints. Obesity (OR=1.8), low testosterone levels (OR=4.28), low quality of life (OR=4.4), an apnea-hypopnea index over 15 (OR=2.75), and obstructive sleep apnea syndrome (OR=2.13) were also significantly associated with a higher risk of ED complaints.

CONCLUSION

EPISONO study indicates that ED complaints are relatively common phenomena, especially among older men. Adequate sleep patterns and normal or high levels of testosterone, which serve as markers for sexual motivation, may be protective against ED. The prevalence of sleep apnea showed a strong impact on erectile function and subsequently negatively affects sexual activity.