Severity Of Sleep-related Breathing Disorders Research Articles

Variations in the sleep-related breathing disorder index on polysomnography between men with HIV and controls: a matched case-control study

BackgroundBoth sleep-related breathing disorders (SRBDs) and HIV infection can interfere with normal sleep architecture, and also cause physical and psychological distress. We aimed to understand the differences in the obstructive patterns, sleep architecture, physical and psychological distress when compared between people living with HIV (PLWH) and matched the severity of SRBDs controls.MethodsA comparative study using matched case-control design was conducted. Men with HIV infection (case group) were enrolled from 2016 to 2019. A control group with HIV seronegative men were matched for SRBDs severity, and were selected from sleep medicine center database for comparison.ResultsThe mean age of the 108 men (including 54 cases and 54 matched controls) was 33.75 years. Central-apnea index (CI) was higher in the case group rather than matched controls (mean CI, 0.34 vs. 0.17, p = 0.049). PLWH had a lower mean percentage of stage 3 sleep (10.26% vs. 13.94%, p = 0.034) and a higher percentage of rapid eye movement sleep (20.59% vs. 17.85%, p = 0.011) compared to matched controls. Nocturnal enuresis and sleepiness causing traffic accidents were more frequent complaint in PLWH compared to controls.ConclusionsEarly detected SRBDs and subtypes in PLWH to begin treatment for the underlying cause could reduce the risk of sleepiness-related traffic accidents.

Prevalences of sleep-related breathing disorders and severity factors in chronic spinal cord injury and abled-bodied individuals undergoing rehabilitation: a comparative study.

The objective of this study was to discern distinguishing characteristics of sleep-related breathing disorders in individuals with chronic spinal cord injury (CSCI) compared with participants without CSCI. Additionally, the study investigated factors associated with sleep-related breathing disorder severity. This is a cross-sectional analysis of 123 individuals without CSCI, 40 tetraplegics, and 48 paraplegics who underwent attended or partially supervised full polysomnography for suspected sleep-related breathing disorders in a rehabilitation center. Polysomnographic, transcutaneous capnography, and clinical data were collected and compared between the groups. Among tetraplegics, apnea-hypopnea index ≥ 30 events/h (67.5%, P = .003), central apnea (17.5%, P = .007), and higher oxygen desaturation index (80.0%, P = .01) prevailed. Sleep-related hypoventilation was present in 15.4% of tetraplegics and 15.8% of paraplegics, compared with 3.2% in participants without CSCI (P = .05). In the group without CSCI and the paraplegic group, snoring and neck circumference were positively correlated with obstructive sleep apnea (OSA) severity. A positive correlation between waist circumference and OSA severity was identified in all groups, and multivariate logistic regression analysis showed that loud snoring and waist circumference had the greatest impact on OSA severity. Severe OSA and central sleep apnea prevailed in tetraplegic participants. Sleep-related hypoventilation was more common in tetraplegics and paraplegics than in participants without CSCI. Loud snoring and waist circumference had an impact on OSA severity in all groups. We recommend the routine implementation of transcutaneous capnography in individuals with CSCI. We underscore the significance of conducting a comprehensive sleep assessment in the rehabilitation process for individuals with CSCI. Souza Bastos P, Amaral TLD, Yehia HC, Tavares A. Prevalences of sleep-related breathing disorders and severity factors in chronic spinal cord injury and abled-bodied individuals undergoing rehabilitation: a comparative study. J Clin Sleep Med. 2024;20(7):1119-1129.

Sleep-related breathing disorders in patients with heart failure with reduced and mildly reduced ejection fraction: main types and their dependence on heart failure etiology

Aim. To identify and study the nature of sleep-related breathing disorders (SBDs) in a cohort of hospitalized patients with heart failure (HF) with reduced and mildly reduced ejection fraction (EF), as well as to clarify the relationship between SBD type, etiology and severity of HF.Material and methods. The study included 117 patients with HF with reduced and mildly reduced ejection fraction hospitalized at the National Medical Research Center for Therapy and Preventive Medicine from 2019 to 2021. All patients underwent clinical and paraclinical examination, including cardiorespiratory sleep study. Patients were divided into three groups according to the type and severity of SBD: no or mild SBD, predominantly with obstructive sleep apnea (OSA) and predominantly with central sleep apnea (CSA). Severity of SBD and clinical data were compared between these groups.Results. A total of 5 patients (4,27%) did not have any SBDs, while 47 (40,17%) were diagnosed with CSA, and 65 (55,56%) — OSA of varying severity. The proportions of patients with moderate and severe CSA and OSA differed insignificantly and amounted to 35,9% (n=42) and 44,4% (n=52), respectively. There were following proportions of diseases related to HF: coronary artery disease (41,88%), nonischemic cardiomyopathy (26,5%), arrhythmogenic cardiomyopathy (15,38%) and other causes (16,24%) (hypertension, myocarditis, heart defects). We found that reduced EF <40%, end-diastolic volume >210 ml, and ventricular ectopy (>300 extrasystoles/day) were associated with CSA, and body mass index >30 kg/m2 was traditionally associated with OSA.Conclusion. More than half of HF patients with reduced and mildly reduced EF have SBDs. Decreased LVEF and ventricular ectopic activity are associated with CSA, while increased body mass index is associated with OSA. Consideration of SBD risk factors may improve patient phenotyping for individualized therapy.

Impact of Spina Bifida on Sleep Quality: Current Insights.

Spina bifida (SB) is one of the most common birth defects in children. The care for patients with SB continues to evolve, and there has been notable improvement in survival outcomes, degree of disability and quality of life for these children. However, patients with SB continue to remain at higher risk for sleep-related breathing disorders (SRBD), unexplained sudden death, and potential alterations in their sleep chronotype. Previous studies report on abnormalities in the spinal cord, brainstem function, and dysfunction of upper airway maintenance as the likely mechanisms behind SRBD that is commonly seen in SB. Most studies looking at prevalence of SRBD in SB have been retrospective studies. A recent prospective study identified a prevalence as high as 42% when a polysomnography (PSG) was completed on all patients regardless of symptomatology. Treatment options vary depending on the type and severity of SRBD and can range widely. Despite advances in care for patients with SB and SRBD, a subset of these patients with myelomeningocele (MMC) continue to experience sudden unexplained death. Studies continue to evaluate ways to stratify which of these patients may be at higher risk of this devastating outcome. Given that SRBD is potentially treatable, early assessment and intervention could become an integral part of a multidisciplinary treatment strategy to optimize long-term medical and neurodevelopmental outcomes for this patient population. By understanding the impact that SB may have on a patient's sleep quality, their biological chronotype and their potential of developing SRBD, a provider may help to optimize the care a patient with SB receives from birth into adulthood.

Sleep-Related Breathing Disorders in Multiple Sclerosis: Prevalence, Features and Associated Factors.

BackgroundMultiple sclerosis (MS) represents a risk factor for sleep disorders, but there are conflicting results about the prevalence and severity of sleep-related breathing disorders (SRBD) in MS. Most available data come from self-administered questionnaires.ObjectiveTo conduct a polysomnographic study in MS focused on SRBD, compared to a group of healthy controls (HC), also considering the neuroimaging findings. To evaluate the impact of SRBD on vigilance, fatigue and depression in MS.MethodsIn this cross-sectional, observational, instrumental study, 67 MS patients (men/women: 20/47; mean age: 50.6±8.2 years) underwent PSG and maintenance of wakefulness test. Findings were compared to 67 age-, sex-, BMI-matched HC, by using parametric (Student’s t-test) and nonparametric statistics (chi-squared test). A subgroup analysis was then performed, evaluating the influence of brainstem (mesencephalic, pontine and medullary) lesions at neuroimaging on instrumental and clinical data: MS patients with at least one brainstem lesion vs MS patients without vs HC.ResultsThe frequency of SRBD was comparable in MS patients and HC. No MS patient had a central apnea index ≥2/h. The respiratory disturbance index (RDI) did not correlate to clinical parameters such as fatigue and depression. Patients with MS were drowsier than HC (47% vs 26%, p = 0.019) and showed a worse sleep pattern, in terms of duration, efficiency and architecture.ConclusionOur study does not provide evidence of an association between MS-specific symptoms such as fatigue, sleepiness, depression and central or obstructive apneas, even in the presence of brainstem lesions.

Comparison of Frequency and Severity of Sleep-Related Breathing Disorders in Children with Simple Obesity and Paediatric Patients with Prader-Willi Syndrome.

Sleep-related breathing disorders (SRBDs) can be present in children with simple obesity and with Prader–Willi syndrome (PWS) and influence an individual diagnostic and treatment approach. We compared frequency and severity of SRBDs in children with simple obesity and with PWS, both without and on recombinant human growth hormone (rhGH) treatment, and correlation of SRBDs with insulin resistance tests. A screening polysomnography-polygraphy (PSG), the oral glucose tolerance test (OGTT) and homeostasis model assessment of insulin resistance (HOMA-IR) were analysed in three groups of patients—with simple obesity (group 1, n = 30, mean age 14.2 years), patients with PWS without the rhGH therapy (group 2, n = 8, mean age 13.0 years) and during the rhGH treatment (group 3, n = 17, mean age 8.9 years). The oxygen desaturation index (ODI) was significantly higher in groups 2 and 3, compared to group 1 (p = 0.00), and hypopnea index (HI) was higher in group 1 (p = 0.03). Apnea–hypopnea index (AHI) and apnea index (AI) results positively correlated with the insulin resistance parameters in groups 1 and 3. The PSG values worsened along with the increasing insulin resistance in children with simple obesity and patients with PWS treated with rhGH that may lead to a change in the patients’ care.

Sleep-disordered breathing and quality of life in patients with chronic cerebrovascular diseas

Introduction. Chronic cerebrovascular disease (CeVD) is usually accompanied by a decrease in the quality of life (QoL). A possible cause of decreased QoL is sleep-disordered breathing. Aim: to assess the frequency of sleep-related breathing disorders and QoL in patients with chronic CeVD. Materials and methods. The study included 100 patients (50 men and 50 women), with an average age of 65 (58; 74.5) years. Cognitive (MoCA-test) and affective disturbances (HADS), severity of daytime sleepiness and fatigue (the Berlin questionnaire to identify patients at risk for the sleep apnea syndrome) were assessed. QoL was evaluated using the SF-36 health survey. Sleep-disordered breathing (SDB) was verified using cardiorespiratory monitoring. The apnoea/hypopnoea index was also calculated. Results. On average, the cognitive impairment score was 25 (23, 27) points; the anxiety level was 6 (4; 9), depression level was 6 (3.5; 8), daytime sleepiness and fatigue were 4 (1.5; 7). QoL was reduced in the majority of patients. SDB was registered in 82% of patients. Multiple comparisons found no differences in QoL scores depending on the presence and severity of sleep-related breathing disorders. Patients with a history of stroke had higher scores for general health ( p = 0.06), mental health ( p = 0.01), and overall psychological health ( p = 0.04). The stroke patients were younger ( p = 0.02) and experienced less daytime sleepiness and fatigue ( p = 0.007). Women had lower QoL scores compared to men. At the same time, the women were older than the men ( p = 0.006) and had higher levels of anxiety ( p = 0.0008). Statistically significant correlations were found between the various QoL components and age, anxiety and depression levels, severity of daytime sleepiness and fatigue, and cognitive dysfunction, but not the apnoea/hypopnoea index. Conclusion. Patients with chronic ischaemic CeVD and SDB had reduced QoL; however, the mental health component remained slightly higher than the physical component. The main factors associated with a decrease in QoL were age, female gender, anxiety and depression levels, and excessive daytime sleepiness/fatigueo.

Sleep-related breathing disorders in patients with pulmonary hypertension

Abstract Introduction There are some evidences of sleep-related breathing disorders (SRBD) association with pulmonary hypertension (PH). Only limited information regarding the SRBD prevalence in pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) patients, is available. Purpose To estimate the features of SRBD and the asymmetric dimethylarginine (ADMA) level in PAH and CTEPH patients and their relationship with the severity of PH. Methods There were included 31 patients (45% male; 55% female) with a verified diagnosis of precapillary PH: 22.6% – with PAH; 9,7% with PAH associated with adult congenital heart disease; 64.5% – with CTEPH; 3.2% with PAH associated with connective tissue disease. Patients underwent a general clinical examination, questionnaires, a comprehensive assessment of respiratory function, a complete polysomnographic study, ECG and ECHO studies, assessment of clinical and biochemical blood tests, including an assessment of ADMA and NT-proBNP levels. Results SRBD of a predominantly obstructive nature were found in 74.2% of the examined: 38.7% were mild, 22.6% were moderate, 12.9% were severe. In 35% of patients, episodes of periodic breathing during sleep were recorded. There was no association SRBD with PH functional class and hemodynamic parameters. Moderate correlation was observed between the apnea-hypopnea index and remodeling indices of the heart chambers according to ECHO: for the end-diastolic size of the left ventricle (ρ=0.54; p=0.005); for an indicator of the ratio of the size of the ventricles (RV/LV) (ρ=−0.41, p=0.05). The presence of SRBD wasn't associated with the level of peripheral blood saturation according to pulse oximetry in sleep and during wakefulness. Negative moderate correlation was observed between NT-proBNP level and the average peripheral blood saturation at night in the entire examined group (ρ=−0.40; p=0.035). All patients showed an increase in ADMA, with no association between ADMA and SRBD severity. Conclusions The incidence of SRBD is extremely high in PAH and CTEPH patients. However, there no association between presence and severity of PH, including with right heart remodeling. But the severity of nocturnal hypoxemia is associated with an increase in NT-proBNP level, a proven marker of poor prognosis in PAH and CTEPH groups of patients. SRBD severity indices (apnea-hypopnea index and desaturation index) are associated with ECHO parameters characterizing remodeling of left heart chambers. Increasing ADMA level as a marker of endothelial dysfunction was related with PH severity, but not with SRBD. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Almazov National Medical Research Centre

0660 The Association Between Sleep-Related Breathing Disorders and Free Flap Reconstruction Surgery in Patients With Oral and Oropharyngeal Cancers During 6-Month Follow-Up

Abstract Introduction Little was known about the association between sleep-related breathing disorders (SRBDs) and oral and oropharynx cancers (OOCs). To clarify the impact of free flap reconstruction on SRBDs, we performed a pilot study to investigate the change of SRBDs severity in patients with OOC before and after flap reconstruction surgery. Methods This study recruited 15 patients who were newly diagnosed with OOCs and expected to receive free flap reconstruction surgery. For each participant, polysomnography tests were performed repeatedly at the time of pre-operative, post-operative 1-week, and post-operative 6-month periods. Results All the subjects were male. Median age was 56 years (range 37-68). Mean of body mass index (BMI) was 24.5 (SD 5.8). Pre-operative apnea-hypopnea index (AHI) was 21.1/hour (SD 20.1). During post-operative 1-week period, BMI was 24.1(SD 5.8) and AHI was 40.2/hour (SD 27.9). During post-operative 6-month period, BMI was 23.4 (SD 3.3) and AHI was 33.3/hour (SD 21.6). Comparison between pre-operative and post-operative 6-month periods, there was no significant difference in BMI, but AHI increased significantly (21.1/hour v.s. 33.3/hour, P = 0.01). Conclusion Our study showed that OOCs patients with free flap reconstruction surgery had significantly increased AHI level during post-operative 1-week period. The SRBDs severity became partial remission after 6 months. We recommend that the head and neck cancer team should pay attention to the SRBDs issues in OOCs patients with free flap reconstruction surgery. Support

Sleep-related breathing disorders in patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension

Background.The data evidence that in patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) nocturnal hypoxemia is associated with poor prognosis. Although, data regarding sleep-related breathing disorders (SRBD) prevalence and their association with pulmonary hypertension (PH) severity are scarce.Objective.To evaluate the prevalence and the structure of SRBD in patients with PAH and CTEPH and the relationship of SRBD with PH severity. Design and methods. In a prospective, single-center study we examined 31 patients (45 % male (n = 14)) with a verified diagnosis of precapillary PH: 22,6 % with IPAH; 9,7 % with PAH associated with congenital heart disease; 64,5 % with CTEPH; 3,2 % with PAH associated with connective tissue disease. Patients underwent a general clinical examination, questionnaires, respiratory tests, full videopolysomnography, electrocardiogram, and heart ultrasound (ECHO) examination, clinical and biochemical blood tests, including the assessment of ADMA and NT-proBNP levels.Results.No differences in SRBD pattern in patients with PAH and CTEPH were observed as well as with the severity of PH. A positive correlation was found between the apnea-hypopnea index (AHI) and the end-diastolic left ventricular dimension (ρ = 0,54; p = 0,005); the ventricular diameter ratio (RV/LV) negatively correlated with AHI (ρ = –0,41; p = 0,05). Low peripheral blood oxygen saturation negatively correlated with NT-proBNP level (ρ = –0,40; p = 0.035). ADMA level was increased in all patients, nevertheless no association between ADMA and SRBD severity was found (χ2= 2,97; p = 0,085).Conclusions.SRBD often occurs among patients with PAH and CTEPH, while the presence of SRBD is not associated with the severity of PH. The severity of SRBD is associated with left heart remodeling. The severity of nocturnal hypoxemia in our group is associated with the increased NT-proBNP level, which is consistent with the idea of a negative prognostic value of nocturnal hypoxemia in patients with PAH and CTEPH.

Vitamin D and pediatrics respiratory diseases

The better understanding of the global activity of vitamin D has led to an intense search for its involvement in non-skeletal diseases. This article presents an updated review of the relationship between vitamin D and pediatric respiratory pathology. A literature search was performed in PUBMED using free terms and MESH terms: vitamin D, asthma, respiratory system diseases, and bronchiolitis. Stu dies in human patients younger than 18 years and animals, published in English and Spanish until 2017 were included. 507 articles were found, of which 43 were included. Indirect evidence suggests a role of vitamin D and fetal lung maturation. In relation to pediatric pulmonary pathology, studies are scarce and inconclusive. Recent meta-analyses performed with individualized evaluation of the participants shows an important protective role of vitamin D supplementation in the prevention of severe asthma exacerbations and acute viral infections. In bronchiolitis, the results are contradictory, with no clear relationship between plasma levels and severity. There is not enough evidence to assess the benefits of vitamin D supplementation in cystic fibrosis and tuberculosis. A direct relationship between the severity of sleep-related breathing disorders and vitamin D plasma levels has recently been proposed, although the exact mechanisms involved in this association are unknown. Current information suggests that vitamin D supplementation may represent a cost-effective strategy in redu cing important causes of infant morbidity and mortality.

Sleep-Related Breathing Disorders in Chiari Malformation Type 1: A Prospective Study of 90 Patients.

The aim of the present study is to describe the prevalence of sleep disorders in a large group of patients with Chiari malformation type 1 (CM-1) and determine the presence of risk factors associated with these abnormalities. Prospective study with consecutive patient selection. We included 90 adult patients with CM-1, defined by the presence of a cerebellar tonsillar descent (TD) ≥3 mm. Clinical, neuroradiological studies, and nocturnal polysomnography (PSG) was carried out. In addition, patients were also subclassified into 2 CM subtypes: CM-1, with the obex above the foramen magnum (FM) and CM-1.5, in which along with a TD ≥3 mm, the obex was located below the FM. We observed a high prevalence (50%) of sleep-related breathing disorders (SRBDs) with predominant hypopnea. Only six patients showed a central apnea index of ≥5. Hypoventilation was observed in only three patients. SRBD severity was associated with male sex, older age, excess weight, and the presence of hydrocephalus. No differences in clinical or PSG parameters were found when comparing CM subtypes (CM-1 and CM-1.5). Sleep architecture study showed decreased sleep efficiency with an increase in arousal and waking after sleep onset. The presence of SRBDs was found to be associated with poorer sleep architecture parameters. This study confirms a high prevalence of SRBDs in patients with CM-1 and CM-1.5, with a predominant obstructive component. Nocturnal PSG recordings should be systematically conducted in these patients, especially those who are male, older, or overweight or those who present hydrocephalus.

Clinical features of obstructive sleep apnea syndrome in patients with acromegaly

To investigate the incidence of sleep-related breathing disorders (SRBDs) in patients with active acromegaly (AM), to specify risk factors influencing apnea/hypopnea index (AHI), and to reveal the specific features of obstructive sleep apnea (OSA) in patients with AM versus those with OSA without AM. Fifty patients with active AM were examined and divided into 3 groups: control group 1 did not differ from the study group in body mass index (BMI); control group 2 did not similar in AHI from the AM group. Polysomnography was done in all the patients. SRBDs were detected in 40 (80%) patients. Obstructive apnea was found in all cases. Correlation analysis revealed the relationships between AHI and gender (AHI was higher in the men), BMI, disease duration, and insulin-like growth factor 1 (GF-1). There were no correlations between AHI and gender, maximum adenoma size, and growth hormone levels. Compared with control group 1, the AM group had a statistically significantly higher median AHI [16 (1-92) and 4.7 (0-31.3) episodes per hour of sleep (p < 0.001)]. In control group 2, the median BMI was considerably higher than in the control group [29.2 (19.9-44.3) and 35 (24-56) kg/m2 (p < 0.001). The detection rate of SRBDs in patients with active AM was 80%, with obstructive disorders being prevalent. There was a positive relationship between SRBD severity and BMI, AM duration, IGF-1 level. Compared to the controls, the patients with AM developed SRBDs similar in severity with lower BMI; severer SRBDs were detected in the patients with active AM with the similar BMI.

At 68 years, unrecognised sleep apnoea is associated with elevated ambulatory blood pressure

After the age of 65 yrs the specific impact of unrecognised sleep-related breathing disorders (SRBD) on 24-h blood pressure (BP) levels remains under debate. We tested the cross-sectional relationship between the severity of obstructive sleep apnoea/hypopnoea (OSAH) and the increase of BP using ambulatory BP monitoring (ABPM) in the PROOF (PROgnostic indicator OF cardiovascular and cerebrovascular events study)-SYNAPSE (Autonomic Nervous System Activity, Aging and Sleep Apnea/Hypopnea study) cohort. 470 subjects (aged 68 yrs) neither treated for hypertension nor diagnosed for SRBD were included. All subjects underwent ABPM, and unattended at-home polygraphic studies. OSAH was defined by an apnoea/hypopnoea index (AHI) >15 · h(-1). The severity of the sleep apnoea was also quantified as the index of dips in oxyhaemoglobin saturation >3% (ODI). Results are expressed in per protocol analysis. Severe OSAH (AHI >30 · h(-1), 17% of subjects) was associated with a significant 5 mmHg increase in both diurnal and nocturnal systolic BP (SBP), and with a nocturnal 3 mmHg increase in diastolic BP (DBP). Systolic (mean SBP >135 mmHg) or diastolic (mean DBP >80 mmHg) hypertension were more frequently encountered in subjects suffering from moderate (AHI 15-30) or severe OSAH. After adjustment, the independent association between severe OSAH and 24-h systolic hypertension remained significant (OR 2.42, 95% CI 1.1-5.4). The relationship was further reinforced when SRBD severity was expressed using ODI >10 · h(-1). The impact of unrecognised SRBD on BP levels also exists at the age of 68 yrs. The hypoxaemic load appears to be the pathophysiological cornerstone for such a relationship.

Depressive symptoms and childhood sleep apnea syndrome

BackgroundThe relationship between sleep and mood regulation is well known, and some reports suggest a key role of sleep-related breathing disorders (SRBD) in the development of the symptomatology of depression, even if no conclusive data are actually found in the clinical literature. The aim of this study was to assess the relationship between SRBD and depressive symptoms in a population of school-aged children.MethodsThe study population comprised 94 children affected by SRBD and 107 healthy children. To identify the severity of SRBD, an overnight respiratory evaluation was performed. All subjects filled out the Italian version of the Children Depression Inventory (CDI) to screen for the presence of depressive symptoms.ResultsThe group with SRBD showed higher CDI scores than the group without SRBD, with a positive correlation found between CDI scores, apnea-hypopnea index, and oxygen desaturation index values. Logistic regression showed that an apnea-hypopnea index ≥ 3 and an oxygen desaturation index ≥ 1 could be risk factors for development of depressive symptoms. According to receiver-operating characteristic curve analysis, the cutoff point for the apnea-hypopnea index that could cause a pathological CDI score (≥19) was >5.66, and the cutoff point for the oxygen desaturation index was >4.2. The limitations of this study are that our data are derived from one single psychometric test and not from a complete psychiatric evaluation, and our subjects came from a small group in southern Italy.ConclusionOur results suggest the importance of mood assessment in children affected by SRBD.

Nightmares: An Under-Diagnosed and Undertreated Condition?

Nightmares: An Under-Diagnosed and Undertreated Condition?

What We Don't Know about Sleep-Related Breathing Disorders in the Elderly

IN THIS ISSUE OF SLEEP, SFORZA, ROCHE, AND COLLEAGUES 1 PRESENT CROSS-SECTIONAL DATA EXAMINING THE ASSOCIATION BETWEEN COGNITIVE function and sleep-related breathing disorders (SRBD) in 827 healthy elderly subjects. An extensive assessment including clinical interview, neurological examination, 12-lead ECG, ECG Holter, and magnetic resonance imaging excluded those with myocardial infarction, previously diagnosed sleep disorders, stroke, dementia, and other cardiac and neurological disorders from the cohort at study entry. Two years after enrollment, 827 (58.5% women, mean age 68 years) of the original cohort had one night of nocturnal unattended at home polygraphy, self-assessed cognitive difficulties in everyday life, depression, anxiety, and daytime sleepiness, and an extensive neuropsychological battery of primarily memory and executive function testing. Noteworthy findings were: (1) 53.8% prevalence of SRBD, defined as apnea + hypopnea index (AHI) > 15; (2) lack of day time sleepiness in the entire group with no significant difference in daytime sleepiness between those with and without SRBD; (3) little hypoxemia in those with SRBD, with no difference in minutes SaO 2 30) demonstrating the lowest scores, but no significant differences in other cognitive function tests; and (6) in multivariate models no significant or strong relationships between cognitive function and severity of SRBD. 1 This study is unique and important, largely because the find ings regarding the relationship between SRBD and cognitive function in healthy older adults were negative on almost every front, with the exception of a consistent deficit in episodic memory. The sample size, strength of the study design, methods, and analysis support the internal consistency and generalizability of the findings. The neuropsychological cognitive function battery was comprehensive, and the measures the investigators used are standard for detecting memory and executive function deficits. Inclusion of another measure of attention, such as the psychomotor vigilance task, may have increased sensitivity to decrements in attention. The approach to data analysis was thoughtful, with targeted bivariate and multivariate analyses to detect differences, if they existed. So here is what we know: in a large population-based sample of healthy 68-year-olds, a comprehensive measure of cognitive function showed that those with SRBD had the same cognitive function (except for a deficit in delayed recall) as those without SRBD. 1 Yet, much remains unknown about SRBD in the elderly. The biggest unknown is the long-term effect of SRBD on cognitive, everyday function, and other common comorbidities such as heart disease in older adults. It is possible that these healthy older adults without cardiac and neurological disease have recent onset SRBD and are thereby without consequent cognitive impairment of significance. We also do not know the earlier severity of SRBD in this sample, further complicating definitive conclusions about short- and long-term effects of SRBD in the elderly. Moreover, if this sample of healthy older adults has had SRBD most of their adult lives, what has protected them from

Do differences in sleep architecture exist between persons with type 2 diabetes and nondiabetic controls?

It has been shown previously that the suppression of slow-wave sleep (SWS) markedly reduced insulin sensitivity and led to an impairment of glucose tolerance. We hypothesized that a decreased amount of SWS is a feature peculiar to subjects with type 2 diabetes. A retrospective case-control study analyzed polysomnographic recordings and covariate data of 22 type 2 diabetic and 22 nondiabetic subjects [n = 44; 8 women, 36 men, aged 57.5 +/- 5.5 years, body mass index (BMI) 33.8 +/- 5.9 kg/m(2), apnea-hypopnea index (AHI) 29.6 +/- 22.2 episodes/hr] matched individually for sex, race, age, BMI, and severity of sleep-related breathing disorders (SRBD). We assessed differences in sleep architecture between the study group and the control group. Primary end points included the percentage of total sleep time spent in each sleep stage. Despite similar age and severity of SRBD, subjects with type 2 diabetes demonstrated a significantly decreased amount of SWS (3.9 +/- 5.95% vs 8.4 +/- 4.57%; p = 0.012), increased percentage time in rapid eye movement sleep (24.1 +/- 12.14% vs 13.8 +/- 6.96%; p = 0.005), and higher arousal index (44.3 +/- 19.53/hr vs 35.7 +/- 12.67/hr; p = 0.037) compared to nondiabetic controls. After adjustment for sex, BMI, AHI, and smoking, age and presence of type 2 diabetes were independent predictors of the decreased SWS percentage (p = 0.001). Variables in this model accounted for 34% of the variance in the SWS percentage in our cohort. Results demonstrated distinct differences in sleep architecture in our cohort with decreased amounts of SWS in type 2 diabetes. These findings suggest that polysomnographic recognition of altered sleep architecture may be partially implicated in the early detection of persons with type 2 diabetes.

Nocturnal Hypoxia and Arterial Lactate Levels in Sleep-Related Breathing Disorders

Lactate may be useful in pointing out the higher risk subgroups in sleep-related breathing disorders (SRBD) with various patterns of hypoxemia. We aimed to search whether morning and night lactate levels are related to apnea-hypopnea, hypoventilation, and hypoxemia in patients with SRBD and to compare it with patients without SRBD (No-SRBD). Eighty patients with suspected SRBD underwent polysomnography (PSG) testing. SRBD patients had obstructive sleep apnea syndrome with or without sleep-related hypoventilation/hypoxemic conditions. Patients without SRBD were in the control group. Measurements included pulmonary function testing, PSG, analysis of arterial blood gases, and arterial lactate before and after PSG. Arterial lactate was compared with SRBD and No-SRBD patients. Morning lactate was significantly higher in the SRBD group than the No-SRBD group (1.65 +/- 0.48 and 1.35 +/- 0.57 mmol/L, respectively) (P = 0.003). Lactate levels at night and the change overnight in lactate levels were not significantly different between groups. After an adjustment for age, gender, and body mass index, lactate levels before PSG were related to the apnea-hypopnea index (beta: 0.004, 95% CI: 0.000-0.008) and the rate of sleep-time spent under 90% oxygen saturation (T90%). The following morning lactate level was correlated with the T90% (beta: 0.005, 95% CI: 0.000-0.010). After an adjustment for lactate levels before PSG, lactate in the morning was correlated with T90% (beta: 0.004, 95% CI: 0.000-0.008). As a marker of tissue hypoxia, arterial lactate may be used to assess the severity of SRBD.

Tongue Base Ultrasound: A Diagnostic Tool for Predicting Obstructive Sleep Apnea

We assessed the value of an ultrasound (US) examination in the diagnostic workup of patients with sleep-related breathing disorders by correlating US measurements with known parameters for the presence and severity of obstructive sleep apnea. Forty-one male patients who complained of snoring and/or daytime somnolence participated. The diagnostic protocol included history-taking, physical examination, polysomnography, and transcervical US examination of the tongue. The US results were compared with all of the other parameters. The US imaging was reliable for demonstrating anatomic structures of the tongue base, discriminating between muscle, mucosa, and blood vessels. The lingual arteries were clearly visualized entering the tongue base at its lower lateral borders. There was a significant relationship between the severity of sleep-related breathing disorders (measured by polysomnography) and the width of the lower tongue base (measured as the distance between the lingual arteries). The distance between the lingual arteries also correlated with physical examination findings and patient complaints of daytime somnolence and the sensation of choking during the night. Tongue base width, measured by US, may influence the severity of obstructive sleep apnea. This is the first demonstration of the possible role of US examination, an inexpensive, noninvasive, and non-irradiating office procedure, in the diagnostic workup for sleep-related breathing disorders.