Obesity and obstructive sleep apnea: pathogenic mechanisms and therapeutic approaches

Prioritising patients for publicly funded bariatric surgery in Queensland, Australia

OBJECTIVES

This study reports the development and pilot application of the Bariatric Surgery Assessment and Prioritisation Tool (BAPT) for use in a public health system. The BAPT was designed as a patient prioritisation instrument to assess patients with excessive weight and type 2 diabetes suitable for bariatric surgery. We assessed whether the instrument successfully identified those who gained the greatest benefits including weight loss, diabetes remission, reduction in comorbidities, and health-related quality of life (HR-QoL).

METHODS

The BAPT instrument was applied to score 292 patients referred for bariatric surgery in Queensland between 2017 and 2020 based on their, body mass index, diabetes status, surgical risk (e.g. pulmonary embolism) and comorbidities (e.g. non-alcoholic steatohepatitis). These data were collected at referral and at 12-months post-surgery for 130 patients and stratified by BAPT scores. Outcomes included clinical and HR-QoL.

RESULTS

Patients' BAPT scores ranged from 12 to 78 (possible range 2-98). Those with higher scores tended to be younger (p < 0.001), have higher BMI (p < 0.001) or require insulin to manage diabetes (p < 0.01). All patients lost similar percentages of body weight (20-25%, p = 0.73) but higher-scoring patients were more likely to discontinue oral diabetes medications (p < 0.001) and the improvement in glycated haemoglobin was four times greater in patients scoring 70-79 points compared to those scoring 20-29 (p < 0.05). Those who scored ≥ 50 on the BAPT were substantially more likely to obtain diabetes remission (57% vs 31%). BAPT scores of 40 and above tended to have greater improvement in HR-QoL.

CONCLUSIONS

The BAPT prioritised younger patients with higher BMIs who realised greater improvements in their diabetes after bariatric surgery. Higher-scoring BAPT patients should be prioritised for bariatric surgery as they have a greater likelihood of attaining diabetes remission.

Endoscopic duodenal-jejunal bypass liner treatment of moderate obstructive sleep apnoea-A pilot study

We aimed to assess the extent to which people with type 2 diabetes or pre-diabetes, obesity (BMI 30-45 kg/m2) and moderate obstructive sleep apnoea (OSA) requiring continuous positive airway pressure ventilation (CPAP) were able to discontinue CPAP following EndoBarrier-related weight loss. We assessed sleep and metabolic parameters before, during and after EndoBarrier in 12 participants with moderate OSA requiring CPAP (75% female, 8/12 [66%] type 2 diabetes, 4/12 [34%] prediabetes, mean ± SD age 52.6 ± 9.7 years, BMI 37.4 ± 3.5 kg/m2, median duration of OSA while on CPAP 9.0 [7.0-15.0] months). With EndoBarrier in-situ, mean ± SD Apnoea Hypopnoea Index (AHI) fell by 9.1 ± 5.0 events/h from 18.9 ± 3.8 to 9.7 ± 3.0 events/h (p < .001) with an associated reduction in symptoms of daytime sleepiness (mean Epworth Sleepiness Score) such that all the 12 participants no longer required CPAP according to National Institute for Health and Care Excellence criteria. After EndoBarrier removal, 10/12 (83%) patients attended follow-up and at 12 months after removal, AHI remained below 15 in 5/10 (50%) patients but in other five the AHI rose above 15 such that restarting CPAP was recommended as justified by their symptoms. Rather than restart CPAP, two patients lost the regained weight and their AHI dropped below 15 again. Thus, 7/10 (70%) of patients were able to remain off CPAP 12 or more months after EndoBarrier removal. These results demonstrate major benefit of EndoBarrier in moderate OSA, allowing all patients to discontinue CPAP during treatment, and with maintenance of improvement at follow-up in 70%. They confirm previously demonstrated metabolic improvements in diabetes and obesity.

The CORE syndrome: an overlap of severe asthma, obstructive sleep apnea, rhinosinusitis, and esophageal reflux

PURPOSE

Asthma, obstructive sleep apnea (OSA), rhinosinusitis, and esophageal reflux are conditions that may overlap, forming a syndrome known as CORE. Whenever clinical remission of severe asthma (SA) is not achieved, it is essential to investigate the presence of comorbidities, in particular the presence of OSA that may lead to the diagnosis of CORE syndrome.

METHODS

The study was conducted on naive patients with SA and concomitant rhinosinusitis and esophageal reflux, referred to our institute since 2018. Patients who did not experience clinical remission were investigated for OSA through a home sleep apnea test. Subsequently, for those diagnosed with OSA, continuous positive airway pressure (CPAP) was proposed and was re-evaluated after 12 months.

RESULTS

Six patients with CORE syndrome were enrolled. The mean apnea-hypopnea index (AHI) was 33.25 ± 20.13 events/h, oxygen desaturation index (ODI) was 28.95 ± 19.95 events/h, and time in bed with SaO2 < 90% (T90) was 26.40 ± 27.22% for which continuous positive airway pressure (CPAP) treatment was proposed but only 3 out of 6 patients accepted. After 12 months, all CPAP-treated patients manifested a significant reduction in daytime sleepiness (ESS score was 6.33 ± 3.8), an improvement in ACT score (+ 8 (+ 32%), + 9 (+ 36%), and + 14 (+ 56%) points), a discontinuation of oral corticosteroids (OCS), an absence of exacerbations, and an improvement of lung function leading to clinical remission of asthma.

CONCLUSION

Whenever facing SA patients, non-responders to therapy, it is important to suspect the presence of CORE syndrome; in particular, the detection and subsequent treatment of OSA would seem to improve the outcome of such patients.

Long-term systemic effects of metabolic bariatric surgery: A multidisciplinary perspective

Background

Obesity is a global health crisis with profound implications on various body systems, contributing to a series of comorbidities. Metabolic Bariatric Surgery (MBS) has emerged as an effective treatment option for severe obesity, with significant weight reduction and potential systemic physiological alterations.

Objectives

This narrative review aims to provide a comprehensive analysis of the long-term effects of MBS on a wide array of body systems, including the heart, liver, kidneys, reproductive system, skin, lungs, digestive tract, pancreas, and blood, as well as related cancers of these organs.

Methods

A systematic search was conducted in academic databases (PubMed, ISI Web of Science, and Scopus) for observational studies and reviews published between July 2000 and December 2023, investigating the association between MBS and the subsequent function of different organ systems. High-quality studies were prioritized to ensure reliable evidence synthesis.

Results

MBS has demonstrated favorable outcomes in reducing cardiovascular disease risk, improving cardiac function, and alleviating heart failure symptoms. It has also been associated with improved respiratory function, remission of obstructive sleep apnea, and reduced cancer incidence and mortality. Additionally, MBS has shown benefits in managing gastrointestinal disorders, enhancing glycemic control, and promoting pancreatic beta-cell regeneration in type 2 diabetes mellitus. However, some methods of MBS are associated with a higher risk of cholelithiasis, GERD, and pancreatic exocrine insufficiency.

Conclusion

MBS has far-reaching systemic effects beyond weight loss, offering potential long-term benefits for various organ systems and comorbidities associated with obesity. For many patients with severe obesity, the potential benefits of Metabolic and Bariatric Surgery (MBS) can outweigh the associated risks. However, careful evaluation by a qualified healthcare professional is crucial to determine candidacy and ensure a successful outcome. Further research is needed to fully elucidate the long-term impacts and tailor personalized treatment approaches.

Associations of Obstructive Sleep Apnea Risk with Obesity, Body Composition and Metabolic Abnormalities in School-Aged Children and Adolescents

The objective of this study is to explore the associations between obesity, body composition, and the self-reported risk of obstructive sleep apnea (OSA) and to examine whether the risk of OSA is related to metabolic abnormalities in children and adolescents aged 6-17 years. Utilizing data from the 2022 to 2023 Beijing Children and Adolescents Health Cohort baseline survey, 5000 school-aged participants were analyzed. OSA risk was assessed via the Pediatric Sleep Questionnaire, with anthropometric and body composition measurements taken. Metabolic markers included blood pressure, lipid levels, blood glucose, and uric acid. Associations were analyzed using logistic regression and generalized linear models. Results showed that 88.6% were low-risk and 11.4% were high-risk for OSA. Overweight (aOR 1.53, 95% CI 1.22-1.92), obesity (aOR 1.94, 95% CI 1.57-2.40), and abdominal obesity (aOR 1.59, 95% CI 1.31-1.93) significantly increased OSA risk. High fat mass was a critical factor, while muscle mass was not, especially in those who were overweight and obese. Associations of OSA risk with metabolic abnormalities were non-significant after adjusting for BMI. Our research highlights the significant associations of obesity and body composition with OSA risk, with child BMI influencing the relationship between OSA and metabolic abnormalities. Future research should explore causative relationships and the enduring impacts of OSA on metabolic health in children.

Associations between Chronic Medical Conditions and Persistent Dietary Supplement Use: The US Military Dietary Supplement Use Study

This longitudinal study examined associations between chronic medical conditions (CMCs) and persistent dietary supplement (DS) use. On two separate occasions, 1.3 ± 0.2 years apart, military service members (SMs) (n = 5778) completed identical questionnaires concerning their DS use in the past 6 months and their demographic and lifestyle characteristics. Medical conditions were obtained from a medical surveillance system six months before the first questionnaire and during the period between questionnaires. Diagnoses were grouped into 19 major (largely systemic) and 9 specific CMCs. Conditions diagnosed in both periods (CMCs) were examined in relation to DS use reported on both questionnaires (persistent DS use). After adjustment for demographic and lifestyle factors, higher odds of persistent DS use were found in 7 of the 19 major CMCs and 5 of the 9 specific CMCs. SMs with a CMC had 1.25 (95% confidence interval [95%CI] = 1.10-1.41) higher adjusted odds of persistent DS use. The three specific CMCs with the highest adjusted odds of persistent DS use were anxiety (odds ratio [OR] = 2.30, 95%CI = 1.36-3.89), depression (OR = 2.12, 95%CI = 1.20-3.73), and gastroesophageal reflux disease (OR = 2.02, 95%CI = 1.02-4.04). Among DS categories, participants with a CMC had higher adjusted odds of persistent vitamins or mineral use (OR = 1.31, 95% CI = 1.12-1.53). Participants with CMCs had a higher prevalence of persistent DS use, especially individual vitamin and mineral use.

Exploring the Shared Genetic Architecture Between Obstructive Sleep Apnea and Body Mass Index

Purpose

The reciprocal comorbidity of obstructive sleep apnea (OSA) and body mass index (BMI) has been observed, yet the shared genetic architecture between them remains unclear. This study aimed to explore the genetic overlaps between them.

Methods

Summary statistics were acquired from the genome-wide association studies (GWASs) on OSA (Ncase = 41,704; Ncontrol = 335,573) and BMI (Noverall = 461,460). A comprehensive genome-wide cross-trait analysis was performed to quantify global and local genetic correlation, infer the bidirectional causal relationships, detect independent pleiotropic loci, and investigate potential comorbid genes.

Results

A positive significant global genetic correlation between OSA and BMI was observed (r g = 0.52, P = 2.85e-122), which was supported by three local signal. The Mendelian randomization analysis confirmed bidirectional causal associations. In the meta-analysis of cross-traits GWAS, a total of 151 single-nucleotide polymorphisms were found to be pleiotropic between OSA and BMI. Additionally, we discovered that the genetic association between OSA and BMI is concentrated in 12 brain regions. Finally, a total 134 expression-tissue pairs were observed to have a significant impact on both OSA and BMI within the specified brain regions.

Conclusion

Our comprehensive genome-wide cross-trait analysis indicates a shared genetic architecture between OSA and BMI, offering new perspectives on the possible mechanisms involved.

A Systematic Review of Risk factors for Sleep Apnea

Background

Sleep apnea, a prevalent global health issue, is characterized by repeated interruptions in breathing during sleep. This systematic review aggregates global data to outline a comprehensive analysis of its associated risk factors.

Purpose

The systematic review underscores the global prevalence of sleep apnea and the universal importance of its early detection and management by delineating key risk factors contributing to its development.

Material and Methods

We conducted a thorough systematic review of international medical databases up to July 31, 2023, including PubMed, Medline, and Cochrane Library, to ensure a wide-ranging collection of data reflective of various populations.

Results

The systematic review identifies several risk factors such as obesity, age, gender, neck circumference, family history, smoking, alcohol use, underlying medical conditions, and nasal congestion, highlighting their prevalence across diverse demographics globally.

Conclusion

Emphasizing lifestyle modifications and proactive interventions, our findings advocate for global health strategies to mitigate the risk of sleep apnea and enhance sleep health worldwide.

Health Inequalities in the Diagnosis and Treatment of Obstructive Sleep Apnea in Children and Adults

Our understanding of the prevalence of obstructive sleep apnea (OSA) in the United States is confounded by significant inequalities in diagnosis and treatment based on gender, race and socioeconomic status. Health literacy and cultural norms contribute to these inequities. Large gaps in data exist, as certain populations like Native Americans, Pacific Islanders, and sexual minorities have been sparsely studied, or not at all. Future research should aim to develop more inclusive diagnostic strategies to address OSA in diverse populations.

Obstructive Sleep Apnea Among Obese Children in Tabuk City, Saudi Arabia

Introduction Obstructive sleep apnea (OSA) is prevalent among children, impacting their well-being. Obesity and related morbidity may lead to serious health disorders. In obese children, OSA may be a risk factor for systemic diseases that negatively affect their quality of life. This study explored the correlation between obesity and OSA among children aged five to 14 years in Tabuk, Saudi Arabia. Methods This cross-sectional study employed an online questionnaire for the parents of 517 children, assessing sociodemographic variables, medical history, and OSA symptoms. The data analysis used Statistical Product and Service Solutions (SPSS; IBM SPSS Statistics for Windows, Armonk, NY) software, employing descriptive and inferential statistics. Results The children were predominantly male (281, 54.4%) and from Tabuk (405, 78.3%), with 158 (30.6%) classified as obese. Symptoms such as snoring (191, 36.9%), daytime fatigue (195, 37.7%), and impact on daily activities (79, 15.3%) were prevalent. OSA scores significantly correlated with BMI categories (p < 0.001), family history of OSA (p < 0.001), and medical conditions including diabetes, hypertension, and high cholesterol (p < 0.05). Correlations showed weak positive associations of age (ρ = 0.159) and height (ρ = 0.229) with OSA score, whereas a strong correlation existed between weight (ρ = 0.531) and OSA score (p < 0.001). Conclusion Obesity demonstrated a strong association with OSA severity among children in Tabuk. Higher BMI categories, a family history of OSA, and certain medical conditions correlated significantly with increased OSA scores. Although age and height displayed weaker associations, weight emerged as a major contributing factor to OSA severity. These findings emphasize the importance of addressing obesity in managing pediatric OSA, advocating for early interventions to mitigate its impact on children's health and well-being.

Phthalate metabolites and sex steroid hormones in relation to obesity in US adults: NHANES 2013-2016

Background

Obesity and metabolic syndrome pose significant health challenges in the United States (US), with connections to disruptions in sex hormone regulation. The increasing prevalence of obesity and metabolic syndrome might be associated with exposure to phthalates (PAEs). Further exploration of the impact of PAEs on obesity is crucial, particularly from a sex hormone perspective.

Methods

A total of 7780 adult participants in the National Health and Nutrition Examination Survey (NHANES) from 2013 to 2016 were included in the study. Principal component analysis (PCA) coupled with multinomial logistic regression was employed to elucidate the association between urinary PAEs metabolite concentrations and the likelihood of obesity. Weighted quartiles sum (WQS) regression was utilized to consolidate the impact of mixed PAEs exposure on sex hormone levels (total testosterone (TT), estradiol and sex hormone-binding globulin (SHBG)). We also delved into machine learning models to accurately discern obesity status and identify the key variables contributing most to these models.

Results

Principal Component 1 (PC1), characterized by mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) as major contributors, exhibited a negative association with obesity. Conversely, PC2, with monocarboxyononyl phthalate (MCNP), monocarboxyoctyl phthalate (MCOP), and mono(3-carboxypropyl) phthalate (MCPP) as major contributors, showed a positive association with obesity. Mixed exposure to PAEs was associated with decreased TT levels and increased estradiol and SHBG. During the exploration of the interrelations among obesity, sex hormones, and PAEs, models based on Random Forest (RF) and eXtreme Gradient Boosting (XGBoost) algorithms demonstrated the best classification efficacy. In both models, sex hormones exhibited the highest variable importance, and certain phthalate metabolites made significant contributions to the model's performance.

Conclusions

Individuals with obesity exhibit lower levels of TT and SHBG, accompanied by elevated estradiol levels. Exposure to PAEs disrupts sex hormone levels, contributing to an increased risk of obesity in US adults. In the exploration of the interrelationships among these three factors, the RF and XGBoost algorithm models demonstrated superior performance, with sex hormones displaying higher variable importance.

Preoperative Assessment of a Patient Undergoing Bariatric Surgery

Over the past few decades, obesity rates in the United States have risen drastically, and with this, there has been a rising demand for bariatric surgery. As such, anesthesiologists need to be familiar with the challenges presented by patients seeking bariatric surgery. Obesity causes pathophysiologic changes which may affect decision-making during the management of these patients. Patients seeking bariatric surgery also have a long, prescribed preoperative course that offers anesthesiologists the opportunity to be involved earlier during the pre-surgical evaluation and optimization process.

Approach the Patient With Obstructive Sleep Apnea and Obesity

Obstructive sleep apnea (OSA) and obesity are highly prevalent and bidirectionally associated. OSA is underrecognized, however, particularly in women. By mechanisms that overlap with those of obesity, OSA increases the risk of developing, or having poor outcomes from, comorbid chronic disorders and impairs quality of life. Using 2 illustrative cases, we discuss the relationships between OSA and obesity with type 2 diabetes, dyslipidemia, cardiovascular disease, cognitive disturbance, mood disorders, lower urinary tract symptoms, sexual function, and reproductive disorders. The differences in OSA between men and women, the phenotypic variability of OSA, and comorbid sleep disorders are highlighted. When the probability of OSA is high due to consistent symptoms, comorbidities, or both, a diagnostic sleep study is advisable. Continuous positive airway pressure or mandibular advancement splints improve symptoms. Benefits for comorbidities are variable depending on nightly duration of use. By contrast, weight loss and optimization of lifestyle behaviors are consistently beneficial.

Effect of physical activity on sleep problems in sedentary adults: a scoping systematic review

This systematic review was steered forward with the aim of analyzing how different forms of exercise could influence the objective and subjective sleep outcome among sedentary adults with sleep problems. A pre-detailed study protocol (PROSPERO ID: CRD42021229649) was used to search for RCTs through five databases. The methodological quality of the included RCTs was assessed by PEDro and studies were included if they scored > 5. Effect size of all outcome measures were calculated using Cohen's d. Of the 4154 studies, 19 studies met the inclusion criteria and underwent quality assessment using 11-point PEDRO scale. 9 studies with PEDro score > 5 were finally included in this systematic review out of which, participants of 4 studies had insomnia (nrange = 37-48, agerange = 44-60 years), 3 studies had poor sleep quality (nrange = 80-275, agerange = 52-70 years) and 2 studies had obstructive sleep apnea syndrome (nrange = 26-68, agerange = 51 years). Majority of studies revealed that physical activity seems to have greater improvement with a large effect size on subjective sleep outcomes among sedentary adults with sleep problems like insomnia, poor sleep quality and OSAS, whereas limited studies and non-significant results were observed on objective sleep outcomes. Physical activity improves sleep outcomes especially among sedentary middle-aged and older adults. More research is needed to examine the effect of physical activity programs on objective sleep outcomes especially in younger sedentary adults with different sleep problems.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-023-00494-w.

Association of obesity with mild traumatic brain injury symptoms, inflammatory profile, quality of life and functional outcomes: a TRACK-TBI Study

OBJECTIVES

Obesity is associated with chronic inflammation, which may impact recovery from mild traumatic brain injury (mTBI). The objective was to assess the role of obesity in recovery of symptoms, functional outcome and inflammatory blood biomarkers after mTBI.

METHODS

TRACK-TBI is a prospective study of patients with acute mTBI (Glasgow Coma Scale=13-15) who were enrolled ≤24 hours of injury at an emergency department of level 1 trauma centres and followed for 12 months. A total of 770 hospitalised patients who were either obese (body mass index (BMI) >30.0) or healthy mass (BMI=18.5-24.9) were enrolled. Blood concentrations of high-sensitivity C reactive protein (hsCRP), interleukin (IL) 6, IL-10, tumour necrosis factor alpha; Rivermead Post-Concussion Symptoms Questionnaire (RPQ), Quality of Life After Brain Injury and Glasgow Outcome Score-Extended reflecting injury-related functional limitations at 6 and 12 months were collected.

RESULTS

After adjusting for age and gender, obese participants had higher concentrations of hsCRP 1 day after injury (mean difference (MD)=0.65; 95% CI: 0.44 to 0.87, p<0.001), at 2 weeks (MD=0.99; 95% CI: 0.74 to 1.25, p<0.001) and at 6 months (MD=1.08; 95% CI: 0.79 to 1.37, p<0.001) compared with healthy mass participants. Obese participants had higher concentrations of IL-6 at 2 weeks (MD=0.37; 95% CI: 0.11 to 0.64, p=0.006) and 6 months (MD=0.42; 95% CI: 0.12 to 0.72, p=0.006). Obese participants had higher RPQ total score at 6 months (MD=2.79; p=0.02) and 12 months (MD=2.37; p=0.049).

CONCLUSIONS

Obesity is associated with higher symptomatology at 6 and 12 months and higher concentrations of blood inflammatory markers throughout recovery following mTBI.

Determination of the risk of obstructive sleep apnea syndrome in individuals aged 18 years and above

OBJECTIVE

This study aimed to increase awareness by determining the risk of obstructive sleep apnea syndrome in individuals aged 18 years and above.

METHODS

The study is a descriptive and cross-sectional study. A total of 633 individuals aged 18 years and above participated in the study. The data were collected online from individuals in the form of describing the demographic characteristics of individuals and with the Berlin survey. The IBM SPSS statistics 26.0 program was used in the analysis of the data.

RESULTS

In this study, 38.9% of individuals were found to be at high risk for obstructive sleep apnea syndrome. A significant relationship was found between the risk of obstructive sleep apnea syndrome and gender, age, body mass index, education level, chronic obstructive pulmonary disease, diabetes, hypertension, presence of cardiovascular diseases, and smoking (p<0.05).

CONCLUSION

The results of this study showed that male gender, increasing age, obesity, presence of chronic disease, and smoking increase the risk of obstructive sleep apnea syndrome. Defining the risk of obstructive sleep apnea syndrome, especially in risky groups, will be effective in planning health care, increasing the effectiveness of treatment, and improving the quality of life. It is recommended to include this diagnosis in health care protocols and to expand its use in order to plan and repeat trainings that will emphasize its importance.

Characteristics and Mechanism of Upper Airway Collapse Revealed by Dynamic MRI During Natural Sleep in Patients with Severe Obstructive Sleep Apnea

Purpose

Upper airway collapse during sleep in patients with obstructive sleep apnea (OSA) is a complex and dynamic phenomenon. By observing and analyzing the dynamic changes in the upper airway and its surrounding tissues during airway obstruction, we aim to reveal dynamic characteristics in different obstruction patterns, and the relationship between anatomical features during normal breathing and dynamic characteristics of airway obstruction.

Patients and Methods

Dynamic MRI was performed in 23 male patients (age range 26-63) with severe OSA diagnosed by overnight polysomnography, and obstruction events were identified from their images. Dynamic changes in parameters of the upper airway and surrounding tissues were measured to assess the key characteristics in different obstruction patterns.

Results

We categorized airway obstruction into four types based on the obstruction location and motion characteristics of tissues during collapse, and detailed the alterations in the airway and surrounding tissues under each obstruction pattern. In all 112 obstruction events extracted from the dynamic images of 23 patients, type A (retropalatal obstruction caused by the soft palate separated from the tongue), BI, BII (both retropalatal obstructions caused by the soft palate attached to the tongue, and C (retropalatal and retroglossal obstruction caused by the soft palate and the tongue), accounted for 28.6%, 44.6%, 12.5%, and 14.3% respectively. In severe OSA patients with tongue and palatal obstruction related to type B or C, the more posterior hyoid position, shorter distance between tongue and uvula, and wider retropalatal space, the larger the tongue displacement and deformation during collapse, and the greater the reduction in airway space.

Conclusion

There are multiple airway obstruction patterns, each with its own anatomical characteristics and behaviors during collapse. Hyoid position, tongue and uvula distance, and retropalatal space play an important role in airway collapse and should be paid more attention in the treatment of OSA.

Pediatric pulmonology year in review 2022: Sleep medicine

Pediatric pulmonology publishes original research, review articles, and case reports on a wide variety of pediatric respiratory disorders. In this article, we summarized the past year's publications in sleep medicine and reviewed selected literature from other journals in this field. We focused on original research articles exploring aspects of sleep-disordered breathing in patients with underlying conditions such as asthma, neuromuscular disorders, and Down syndrome. We also explored sleep-disordered breathing risk factors, monitoring, diagnosis, and treatment; and included recent recommendations for drug-induced sleep endoscopy and ways to monitor and improve PAP adherence remotely.

Snoring might be a warning sign for metabolic syndrome in nonobese Korean women

Metabolic syndrome (MetS) is an underlying cause of various diseases and is strongly associated with mortality. In particular, it has been steadily increasing along with changes in diet and lifestyle habits. The close relationship between sleep apnea and MetS is well established. In addition, these two diseases share a common factor of obesity and have a high prevalence among obese individuals. Nevertheless, the association can vary depending on factors, such as race and sex, and research on the relatively low obesity rates among East Asians is lacking. This study aimed to investigate the association between snoring and MetS in nonobese Koreans. A total of 2478 participants (827 men and 1651 women) were enrolled in the Korean National Health and Nutrition Examination Survey from 2019 to 2020. We used the National Cholesterol Education Program Adult Treatment Panel III criteria for MetS and a snoring questionnaire. Logistic regression analysis was used to measure the association between MetS and various confounding factors according to age and sex in participants with body mass index (BMI) < 23 kg/m2. MetS was significantly higher in participants with snoring than in those without snoring (26.9% vs. 19.6%; p = 0.007). In multivariate logistic regression analysis, age (odds ratio [OR] 1.070, 95% confidence interval [CI] 1.059-1.082, p < .001), sex (OR 1.531, 95% CI 1.139-2.058, p = 0.005), and snoring (OR 1.442, 95% CI 1.050-1.979, p = 0.024) were significantly associated with MetS in patients with a BMI < 23 kg/m2. Finally, regression analysis showed that snoring was significantly associated with MetS in women with a BMI of less than 23 kg/m2, especially with younger ages (40-49 years, OR 4.449, 95% CI 1.088 to 18.197, p = 0.038). Snoring was closely associated with MetS in women aged 40-50 years with a BMI of less than 23 kg/m2 compared to other participants. However, the association was not found in women aged 60 and over. Therefore, sufficient consideration should be given to the possibility of MetS when snoring is present in nonobese middle-aged Asian women.

The Medical Burden of Obesity and Overweight in the US Military: Association of BMI with Clinically Diagnosed Medical Conditions in United States Military Service Members

BACKGROUND

A high BMI is associated with various medical conditions, notably type 2 diabetes, cardiovascular disease, and mental health disorders. In the US military, BMI increased linearly between 1975 and 2015.

OBJECTIVE

This cross-sectional study investigated the associations between BMI and a comprehensive range of clinically diagnosed medical conditions (CDMCs) in US military service members (SMs).

METHODS

A stratified random sample of SMs (n=26,177) completed an online questionnaire reporting their height, weight, and demographic/lifestyle characteristics. Medical conditions for 6 mo before questionnaire completion were obtained from a comprehensive military electronic medical surveillance system and grouped into 39 CDMCs covering both broad (largely systemic) and specific medical conditions. BMI was calculated as weight/height2 (kg/m2). The prevalence of CDMCs was compared among normal weight (<25.0 kg/m2), overweight (25.0-29.9 kg/m2), and obese (≥30 kg/m2) SMs.

RESULTS

After multivariable adjustment for demographic/lifestyle characteristics, higher BMI was associated with higher odds of a diagnosed medical condition in 30 of 39 CDMCs, with all 30 displaying dose-response relationships. The 5 major CDMCs with the largest odds ratios comparing obese to normal weight were endocrine/nutritional/metabolic diseases (OR=2.67, 95%CI=2.24-3.15), nervous system diseases (odds ratio [OR]=2.59, 95%CI=2.32-2.90), circulatory system diseases (OR=2.56, 95%CI=2.15-3.06), musculoskeletal system diseases (OR=1.92, 95%CI=1.76-2.09), and mental/behavioral disorders (OR=1.69, 95%CI=1.51-1.90). Compared with normal weight SMs, overweight or obese SMs had a higher number of CDMCs (1.8±1.9 vs. 2.0±2.0 and 2.5±2.3, mean ± standard deviation, respectively, P<0.01).

CONCLUSIONS

In a young, physically active population, higher BMI was associated with a host of medical conditions, even after adjustment for demographic/lifestyle characteristics. The US Department of Defense should improve nutrition education and modify other factors that contribute to overweight and obesity. This study demonstrates that the medical burden of obesity is substantial in overweight and obese SMs.

OSA Is Associated With the Human Gut Microbiota Composition and Functional Potential in the Population-Based Swedish CardioPulmonary bioImage Study

BACKGROUND

OSA is a common sleep-breathing disorder linked to increased risk of cardiovascular disease. Intermittent upper airway obstruction and hypoxia, hallmarks of OSA, have been shown in animal models to induce substantial changes to the gut microbiota composition, and subsequent transplantation of fecal matter to other animals induced changes in BP and glucose metabolism.

RESEARCH QUESTION

Does OSA in adults associate with the composition and functional potential of the human gut microbiota?

STUDY DESIGN AND METHODS

We used respiratory polygraphy data from up to 3,570 individuals 50 to 64 years of age from the population-based Swedish Cardiopulmonary bioimage Study combined with deep shotgun metagenomics of fecal samples to identify cross-sectional associations between three OSA parameters covering apneas and hypopneas, cumulative sleep time in hypoxia, and number of oxygen desaturation events with gut microbiota composition. Data collection about potential confounders was based on questionnaires, onsite anthropometric measurements, plasma metabolomics, and linkage with the Swedish Prescribed Drug Register.

RESULTS

We found that all three OSA parameters were associated with lower diversity of species in the gut. Furthermore, in multivariable-adjusted analysis, the OSA-related hypoxia parameters were associated with the relative abundance of 128 gut bacterial species, including higher abundance of Blautia obeum and Collinsella aerofaciens. The latter species was also independently associated with increased systolic BP. Furthermore, the cumulative time in hypoxia during sleep was associated with the abundance of genes involved in nine gut microbiota metabolic pathways, including propionate production from lactate. Finally, we observed two heterogeneous sets of plasma metabolites with opposite association with species positively and negatively associated with hypoxia parameters, respectively.

INTERPRETATION

OSA-related hypoxia, but not the number of apneas/hypopneas, is associated with specific gut microbiota species and functions. Our findings lay the foundation for future research on the gut microbiota-mediated health effects of OSA.

Obstructive sleep apnea and orofacial myofunctional aspects in obesity

PURPOSE

This study aimed to evaluate the quality of sleep, presence of obstructive sleep apnea (OSA), and its relationship with the presence of snoring, cephalometric characteristics, degree of collapse of the upper airways, and orofacial myofunctional profile in obese and overweight individuals.

METHODS

All participants completed polysomnography, as well as sleep and snoring questionnaires. We further performed orofacial, otorhinolaryngological, and anthropometric evaluations on all participants.

RESULTS

A total of 102 adults, comprising 29 obese, 21 overweight, and 52 eutrophic individuals of both sexes participated in this study. We observed a high prevalence of snoring in both obese and overweight (100%), and in 65% of eutrophic individuals. Among the obese subjects 58% had a severe degree of OSA, whereas 4% of eutrophic subjects presented a risk for OSA development. Sleep quality was related to body mass index (BMI) and cervical and abdominal circumference. All obese and overweight individuals presented with orofacial myofunctional alterations such as facial asymmetry, alteration of the maxilla-jaw relationship, inadequate tongue posture, changes in masticatory pattern and swallowing, and inadequate general orofacial myofunctional condition. Airway obstructions at the retropalatal and retrolingual levels > 75% were observed in at least 48% of the individuals.

CONCLUSION

Obese and overweight individuals presented a higher risk for the development of OSA compared with eutrophic patients, and obese individuals presented a greater severity of OSA. The higher the BMI and greater the cervical and abdominal circumferences, the higher the prevalence of OSA, worse the quality of sleep, and more serious orofacial myofunctional characteristics in this population.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Pharmacotherapy for obstructive sleep apnea: targeting specific pathophysiological traits

INTRODUCTION

The pathophysiology of obstructive sleep apnea (OSA) is multi-factorial and complex. Varying OSA's pathophysiological traits have been identified, including pharyngeal collapsibility, upper airway muscle reactivity, arousal threshold, and regulation of the ventilatory drive. Being CPAP of difficult tolerance and other interventions reserved to specific subpopulations new pharmacological treatments for OSA might be resolutive.

AREAS COVERED

Several existing and newly developed pharmacological drugs can impact one or more endotypes and could therefore be proposed as treatment options for sleep disordered breathing. With this review we will explore different pathophysiological traits as new targets for OSA therapy. This review will summarize the most promising pharmacological treatment for OSA accordingly with their mechanisms of action on upper airway collapsibility, muscle responsiveness, arousal threshold, and loop gain.

EXPERT OPINION

Only understanding the pathophysiological traits causing OSA in each patient and placing the disease in the framework of patient comorbidities, we will be able to evolve interventions toward OSA. The development of new drug's combinations will permit different approaches and different choices beside conventional treatments. In the next future, we hope that sleep specialists will select the treatment for a specific patient on the base of its pathophysiology, defining a precision medicine for OSA.

Pulmonary Function Test and Obstructive Sleep Apnea Hypopnea Syndrome in Obese Adults: A Retrospective Study

Objective

We explore risk factors related to severe obstructive sleep apnea (OSA) in obese patients, including pulmonary ventilation function, diffusion function, and impulse oscillometry (IOS) data.

Methods

The medical records of 207 obese patients who were prepared to undergo bariatric surgery in a hospital from May 2020 to September 2021 were retrospectively reviewed. Polysomnography (PSG), pulmonary ventilation function, diffusion function, and IOS parameters were collected according to the ethical standards of the institutional research committee (registration number: KYLL-202008-144). Logistic regression analysis was used to analyze the related independent risk factors.

Results

There were significantly statistical difference in a number of pulmonary ventilation and diffusion function parameters among the non-OSAHS group, the mild-to-moderate OSA group, and the severe OSA group. However, only airway resistance parameters R5%, R10%, R15%, R20%, R25%, and R35% increased with increasing OSA severity and were positively correlated with apnea hypopnea index (AHI). Age (P = 0.012, 1.104 (1.022, 1.192)), body mass index (P< 0.0001, 1.12 (1.057, 1.187)), gender (P = 0.003, 4.129 (1.625, 10.49)), and R25% (P = 0.007, 1.018 (1.005, 1.031)) were independent risk factors for severe OSA. In patients aged 35 to 60, RV/TLC (P = 0.029, 1.272 (1.025, 1.577)) is an independent risk factor for severe OSA.

Conclusion

R25% was an independent risk factor for severe OSA in obese individuals, while RV/TLC was also an independent risk factor in those aged 35 to 60. Pulmonary function tests (PFTs), particularly IOS levels, are recommended to assess severe OSA in obese patients.

Health Complications of Obesity: 224 Obesity-Associated Comorbidities from a Mechanistic Perspective

Obesity is associated with a wide range of comorbidities that transverse multiple specialties in clinical medicine. The development of these comorbidities is driven by various mechanistic changes including chronic inflammation and oxidative stress, increased growth-promoting adipokines, insulin resistance, endothelial dysfunction, direct loading and infiltrative effect of adiposity, heightened activities of the renin-angiotensin-aldosterone system and sympathetic nervous system, impaired immunity, altered sex hormones, altered brain structure, elevated cortisol levels, and increased uric acid production, among others. Some of the comorbidities might develop secondary to one or more other comorbidities. Considering the obesity-associated comorbidities in the context of the mechanistic changes is helpful in understanding these conditions and in guiding treatment and future research.

Long-term trends in body mass index throughout upper airway stimulation treatment: does body mass index matter?

STUDY OBJECTIVES

Upper airway stimulation is a surgical option for patients with obstructive sleep apnea who fail other forms of noninvasive treatment. Current guidelines recommend a baseline body mass index (BMI) below 32 kg/m2 for eligibility. In this study, we identify trends in BMI before and after upper airway stimulation to characterize the influence of BMI on treatment success.

METHODS

Patients underwent upper airway stimulation implantation between 2016 and 2021. Sleep study data were collected from preoperative and most recent postoperative sleep study. BMI data were collected and compared across the following time points: preoperative sleep study (BMI-1), initial surgeon consultation (BMI-2), surgery (BMI-3), titration polysomnogram (BMI-4), and second postoperative sleep study (BMI-5). Patients were categorized into groups (BMI ≥32 [BMI32], 25 ≤ BMI <32 [BMI25], BMI <25 [BMI18]) based BMI-1, and clinical outcomes were compared.

RESULTS

253 patients were included. The BMI32 group showed a significant decrease in BMI between BMI-1 and BMI-3 (33.9 vs 32.2; P < .001) and a significant increase in BMI between BMI-3 and BMI-5 (32.2 vs 33.0; P = .047). Apnea-hypopnea index improvement and treatment success rate were not significantly different between groups. On univariate and multivariable logistic regression, a lower BMI-5 was significantly predictive of treatment success (odds ratio: 0.88; 95% confidence interval: 0.79-0.97; P = .016). BMI-5 was also significantly associated with improvement in apnea-hypopnea index (P = .002). Other BMI time points were not associated with measures of treatment success.

CONCLUSIONS

Reduced BMI after upper airway stimulation implantation, as opposed to baseline BMI, predicted treatment success. These findings may guide patient counseling, with implications for long-term adherence and therapy success.

CITATION

Renslo B, Virgen CG, Sawaf T, et al. Long-term trends in body mass index throughout upper airway stimulation treatment: does body mass index matter? J Clin Sleep Med. 2023;19(6):1061-1071.

A Prospective Study on Obstructive Sleep Apnea, Clinical Profile and Polysomnographic Variables

Background: Obstructive sleep apnea (OSA) is characterized by recurring episodes of pharyngeal collapse, which can partially or completely block airflow during sleep and cause cardiorespiratory and neurological imbalances. Therefore, the purpose of this study was to assess OSA and the relationship between AHI and polysomnographic characteristics in OSA patients. Methodology: A prospective study was conducted at the Department of Pulmonology and Sleep Medicine for two years. All 216 participants underwent polysomnography, and 175 of them were reported to have OSA (AHI ≥ 5), while 41 of them did not (AHI < 5). ANOVA and Pearson's correlation coefficient test were performed. Results: In terms of the study population's average AHI, Group 1 had 1.69 ± 1.34, mild OSA had 11.79 ± 3.55, moderate OSA had 22.12 ± 4.34, and severe OSA was found to have 59.16 ± 22.15 events/hour. The study group's average age was 53.77 ± 7.19 out of 175 OSA patients. According to AHI, the BMI for mild OSA was 31.66 ± 8.32 kg/m², for moderate OSA, it was 30.52 ± 3.99 kg/m², and for severe OSA, it was 34.35 ± 8.22 kg/m². The average number of oxygen desaturation events and snoring duration were 25.20 ± 18.63 and 24.61 ± 28.53 min, respectively. BMI (r = 0.249, p < 0.001), average oxygen saturation (r = -0.387, p < 0.000), oxygen desaturation (r = 0.661, p < 0.000), snoring time (r = 0.231, p < 0.002), and the number of snores (r = 0.383, p < 0.001) were the polysomnographic variables that showed significant correlations with AHI in the study group. Conclusions: In this study, a substantial prevalence of obesity and a high OSA frequency were found in men. Our research showed that individuals with obstructive sleep apnea experience nocturnal desaturations. Polysomnography is the primary test for early detection of this treatable condition.

Five-year Transitions of Symptom Subtypes in Untreated Obstructive Sleep Apnea

Objectives

It is unknown if symptom subtypes of obstructive sleep apnea (OSA) transition over time and what clinical factors may predict transitions.

Methods

Data from 2,643 participants of the Sleep Heart Health Study with complete baseline and 5-year follow-up visits were analyzed. Latent Class Analysis on 14 symptoms at baseline and follow up determined symptom subtypes. Individuals without OSA (AHI<5) were incorporated as a known class at each time point. Multinomial logistic regression assessed the effect of age, sex, body mass index (BMI) and AHI on specific class transitions.

Results

The sample consisted of 1,408 women (53.8%) and mean (SD) age 62.4 (10.5) years. We identified four OSA symptom subtypes at both baseline and follow-up visits: minimally symptomatic, disturbed sleep, moderately sleepy and excessively sleepy . Nearly half (44.2%) of the sample transitioned to a different subtype from baseline to follow-up visits; transitions to moderately sleepy were the most common (77% of all transitions). A five-year older age was associated with a 6% increase in odds to transit from excessively sleepy to moderately sleepy [OR (95% CI) = 1.06 (1.02, 1.12)]. Women had 2.35 times higher odds (95% CI: 1.27, 3.27) to transition from moderately sleepy to minimal symptoms . A 5-unit increase in BMI was associated with 2.29 greater odds (95% CI: 1.19, 4.38) to transition from minimal symptoms to excessively sleepy .

Interpretation

While over half of the sample did not transition their subtype over 5 years, among those who did, the likelihood of transitioning between subtypes was significantly associated with a higher baseline age, higher baseline BMI and with women, but was not predicted by AHI.

Clinical Trials

Sleep Heart Health Study (SHHS) Data Coordinating Center, (SHHS) https://clinicaltrials.gov/ct2/show/NCT00005275 , NCT00005275.

Statement of significance

There is very little research assessing symptom progression and its contributions to clinical heterogeneity in OSA. In a large sample with untreated OSA, we grouped common OSA symptoms into subtypes and assessed if age, sex, or BMI predicted transitions between the subtypes over 5 years. Approximately half the sample transitioned to a different symptom subtype and improvements in symptom subtype presentation were common. Women and older individuals were more likely to transition to less severe subtypes, while increased BMI predicted transition to more severe subtype. Determining whether common symptoms like disturbed sleep or excessive daytime sleepiness occur early in the course of the disease or as a result of untreated OSA over an extended period can improve clinical decisions concerning diagnosis and treatment.

A First Look at Childhood Abuse in Women with Obstructive Sleep Apnea

Study objectives. Women who experienced childhood sexual abuse have higher rates of obesity, a risk factor for obstructive sleep apnea (OSA). We assessed if prior childhood sexual abuse was more common in women with OSA vs. control, with possible mediation by obesity. Methods . We studied 21 women with OSA (age mean±s.d. 59±12 years, body mass index (BMI) 33±8 kg/m 2 , respiratory event index [REI] 25±16 events/hour, Epworth Sleepiness Scale [ESS] 8±5) and 21 women without OSA (age 53±9 years, BMI 25±5 kg/m 2 , REI (in 7/21 women) 1±1 events/hour, ESS 5±3). We evaluated four categories of trauma (general trauma, physical, emotional, and sexual abuse) with the early trauma inventory self-report-short form (ETISR-SF). We assessed group differences in trauma scores with independent samples t-tests and multiple regressions. Parametric Sobel tests were used to model BMI as a mediator for individual trauma scores predicting OSA in women. Results. Early childhood sexual abuse reported on the ETISR-SF was 2.4 times more common in women with vs. without OSA ( p =0.02 for group difference). Other trauma scores were not significantly different between women with and without OSA. However, BMI was a significant mediator ( p =0.02) in predicting OSA in women who experienced childhood physical abuse. Conclusions. Childhood sexual abuse was more common in a group of women with OSA than those without OSA. Additionally, BMI was a mediator for OSA of childhood physical but not sexual abuse. There may be physiological impacts of childhood trauma in women that predispose them to OSA.

Sex Differences in 90-Day Functional Outcomes for Acute Ischemic Stroke Patients With Obstructive Sleep Apnea

Background Obstructive sleep apnea (OSA) is characterized by repeated episodes of either full or partial obstruction of the upper airway. OSA is an independent risk factor for acute ischemic stroke (AIS) and a contributor to other key risk factors. OSA may damage endothelial and brain tissues and worsen outcomes following AIS. We aimed to evaluate the impact of sex differences on 90-day functional outcomes following AIS in an OSA population, as measured by the modified Rankin Scale (mRS) score. Methodology We performed a retrospective study of patients with OSA and AIS from the Houston Methodist Hospital Outcomes-Based Prospective Endpoints in Stroke (HOPES) Registry from 2016 to 2022. Patients with charts that noted a diagnosis of OSA before AIS or within the 90 days following AIS were included. A multivariable logistic regression model was constructed adjusting for demographics, first admit National Institutes of Health Stroke Scale (NIHSS), and comorbidities on the binary outcome. The odds ratios (ORs) and 95% confidence intervals (CIs) were reported, providing likelihood estimates of a shift to higher mRS for a given comparison between females (reference category) and males. Statistical significance was defined as two-tailed p-values <0.05 for all tests. Results From the HOPES registry, 291 females and 449 males were found to have OSA. Males had a higher proportion of comorbid conditions such as atrial fibrillation (15% vs. 9%, p = 0.014) and intracranial hemorrhage compared to females (6% vs. 2%, p = 0.020). The multivariate logistic regression model showed that males were at two times higher risk for developing poor functional outcomes at 90 days (OR = 2.35, 95% CI = 1.06-5.19), p < 0.001). Conclusions Males were found to have two times higher risk for developing poor functional outcomes at 90 days. This may be due to more severe oxygen desaturation, increased susceptibility to oxidative stress, and greater frequency of full airway obstruction in males. Greater emphasis on early diagnosis and treatment of OSA may be necessary to reduce the disproportionate incidence of poor functional outcomes, particularly among apneic male stroke survivors.

Using Machine-Learning to Predict Sleep-Disordered Breathing Diagnosis From Medical Comorbidities and Craniofacial Features

Objectives This paper attempts to use machine-learning (ML) algorithms to predict the presence of sleep-disordered breathing (SDB) in a patient based on their body habitus, craniofacial anatomy, and social history. Materials and methods Data from a group of 69 adult patients who attended a dental clinic for oral surgeries and dental procedures in the last 10 years was used to train machine-learning models to predict whether a subject is likely to have SDB based on input information such as age, gender, smoking history, body mass index (BMI), oropharyngeal airway (Mallampati assessment), forward head posture (FHP), facial skeletal pattern, and sleep quality. Logistic Regression (LR), K-nearest Neighbours (kNN), Support Vector Machine (SVM) and Naïve Bayes (NB) were selected as these are the most frequently used supervised machine-learning models for classification of outcomes. The data was split into two sets for machine training (80% of total records) and the remaining was used for testing (validation). Results Initial analysis of collected data showed overweight BMI (at 25 or above), periorbital hyperchromia (dark circle eyes), nasal deviation, micrognathia, convex facial skeletal pattern (class 2) and Mallampati class 2 or above have positive correlations with SDB. Logistic Regression was found to be the best performer amongst the four models used with an accuracy of 86%, F1 score of 88% and area under the ROC curve (AUC) of 93%. LR also had 100% specificity and 77.8% sensitivity. Support Vector Machine was the second-best performer with an accuracy of 79%, F1 score of 82% and AUC of 93%. k-Nearest Neighbours and Naïve Bayes performed reasonably well with F1 scores of 71% and 67%, respectively. Conclusions This study demonstrated the feasibility of using simple machine-learning models as a credible predictor of sleep-disordered breathing in patients with structural risk factors for sleep apnoea such as craniofacial anomalies, neck posture and soft tissue airway obstruction. By utilising higher-level machine-learning algorithms, it is possible to incorporate a broader range of risk factors, including non-structural features like respiratory diseases, asthma, medication use, and more, into the prediction model.

Determinants of awake oropharyngeal volume reduction between sitting and supine positions in children evaluated for snoring

Pharyngeal collapsibility is a major determinant of obstructive sleep apnea (OSA) pathophysiology, but its anatomical predictors in children are largely unknown. We hypothesised that anatomical (tonsillar hypertrophy, narrow palate, nasal obstruction, dental/skeletal malocclusion, obesity) and OSA-related (apnea-hypopnea index, AHI) parameters could be related to a measure of awake pharyngeal collapsibility. We performed acoustic pharyngometry in children evaluated for suspected OSA, allowing us to measure the reduction of oropharyngeal volume in supine versus sitting position normalised for the volume in supine position (ΔV%), a measure of pharyngeal collapsibility. In addition to polysomnography and a clinical examination (anatomical parameters), acoustic rhinometry was used to assess nasal obstruction. A total of 188 snoring children were included, 118 (63%) of whom were obese and 74 (39%) of whom had moderate to severe OSA (AHI ≥5/h). The median (25th-75th percentiles) ΔV% in the whole population was 20.1% (4.7; 43.3). ΔV% was independently and positively associated with AHI (p = 0.023), z-score of BMI (p = 0.001), tonsillar hypertrophy (p = 0.007), narrow palate (p = 0.035), and African (p < 0.001) ancestry. By contrast, ΔV% was not modified by dental or skeletal malocclusion, Friedman palate position class or nasopharyngeal obstruction. Tonsillar hypertrophy, obesity, narrow palate and African ancestry are independently associated with an increase in pharyngeal collapsibility in snoring children, thus increasing the risk of OSA. Increased pharyngeal compliance in African children may explain the increased risk of residual OSA after adenotonsillectomy observed in this population.

Effect of the Implementation of a Structured Diet Management Plan on the Severity of Obstructive Sleep Apnea: A Systematic Review

PURPOSE OF REVIEW

The prevalence of obstructive sleep apnea (OSA) is increasing worldwide, in line with the increase in obesity prevalence. Taken into consideration the low compliance rates to continuous positive airway pressure (CPAP) treatment, and since obesity is a risk factor for OSA, these patients should receive additional counseling for weight loss through a diet plan. The aim of this review is to examine the role of a structured diet management plan on OSA severity, nocturnal oxygen indices, and subjective sleep parameters.

RECENT FINDINGS

Τhis systematic review of the literature resulted in four studies and demonstrated that severity of OSA, assessed by the apnea-hypopnea index, is reduced by a dietary management plan when delivered through an educational program. Moreover, nocturnal oxygenation is improved, as well as subjective sleep parameters, when initiating a diet on top of CPAP use. In summary, the present systematic review reports on the beneficial effects of a structured diet management plan in patients with OSA. Although CPAP remains the gold standard of OSA treatment, a specific dietary plan should be sought when managing patients with OSA. Nevertheless, still the evidence is low, and further research on this field is needed to reduce the burden of OSA.

Respiratory complications of obesity: from early changes to respiratory failure

Obesity is a significant and increasingly common cause of respiratory compromise. It causes a decrease in static and dynamic pulmonary volumes. The expiratory reserve volume is one of the first to be affected. Obesity is associated with reduced airflow, increased airway hyperresponsiveness, and an increased risk of developing pulmonary hypertension, pulmonary embolism, respiratory tract infections, obstructive sleep apnoea and obesity hypoventilation syndrome. The physiological changes caused by obesity will eventually lead to hypoxic or hypercapnic respiratory failure. The pathophysiology of these changes includes a physical load of adipose tissue on the respiratory system and a systemic inflammatory state. Weight loss has clear, well-defined benefits in improving respiratory and airway physiology in obese individuals.

Altered cerebral blood flow and white matter during wakeful rest in patients with obstructive sleep apnea: a population-based retrospective study

OBJECTIVES

To explore changes in cerebral blood flow (CBF) and white matter during wakeful rest in patients with obstructive sleep apnea (OSA).

METHODS

The subjects comprised OSA patients and age- and sex-matched non-sleep apnea (NSA) subjects from December 2020 to December 2021. All subjects underwent structural and arterial spin labeling MRI examinations using a 3.0 T MRI scanner. Intergroup differences in regional and global CBF and white matter hyperintensities (WMHs) were analyzed.

RESULTS

In this study, 100 (74 males) of 750 (439 males) subjects were diagnosed with OSA, so the prevalence of OSA in the general population was 13.3% (100/750), with 16.9% (74/439) in males and 8.4% (26/311) in females. Excluding four patients with incomplete imaging data, 96 OSA patients and 103 age- and sex-matched NSA subjects were included. At global level, OSA patients showed significantly decreased CBF values in gray matter and whole brain compared to NSA subjects (gray matter: p = 0.010; whole brain: p = 0.021). No significant difference in CBF values was found in WM between the two groups (p = 0.250). At regional level, compared with NSA subjects, patients with OSA exhibited significantly decreased regional CBF values mainly in right parietal lobe and right temporal lobe. Moreover, OSA patients had significantly higher WMHs burden than NSA subjects (p = 0.017).

CONCLUSIONS

OSA patients exhibit decreased global and regional CBF values and increased WMHs burden.

ADVANCES IN KNOWLEDGE

These findings provide a basis for exploring neuropathological changes of OSA and for early and appropriate treatment.

Three-dimensional orthodontic imaging in children across the age spectrum and correlations with obstructive sleep apnea

STUDY OBJECTIVES

To determine baseline facial convexity measurements in children with obstructive sleep apnea (OSA) across the age spectrum.

METHODS

Polysomnogram, stereophotogrammetry, and biometric data were collected from children aged 0-18 years who were being investigated for OSA. Analyses evaluated differences in facial convexity according to OSA severity and other sleep parameters, while adjusting for age, ethnicity, and sex.

RESULTS

Ninety-one children, aged 0.05-16.02 years, met the inclusion criteria for this study. Initial analysis showed that the logarithm of age had a significant effect on facial convexity (P = 8.3·10-7) with significant effects of sex (P = 1.3·10-2), while excluding OSA. Ordinal logistic regression taking into consideration age, sex, weight, height, and ethnicity with OSA severity categorized as obstructive apnea-hypopnea index negative, mild, moderate, or severe showed that facial convexity was associated with OSA severity (P = 2.2·10-3); an increasing obtuse angle of convexity increased the tendency to be classified as having severe OSA.

CONCLUSIONS

Using three-dimensional imaging, we found an added impact of infancy on changes of facial convexity with age. While modeling could describe facial convexity without any OSA-associated sleep parameters, differences in facial convexity were present among groups with different levels of OSA severity adjusted for growth (age, weight, and height), sex, and ethnicity. The method provides a safer and cheaper alternative to other medical imaging techniques in children and holds potential for future use in studies of craniofacial structure.

CITATION

Tyler G, Machaalani R, Waters KA. Three-dimensional orthodontic imaging in children across the age spectrum and correlations with obstructive sleep apnea. J Clin Sleep Med. 2023;19(2):275-282.

Nasopharyngeal luminal change on cervical radiography in brachycephalic dogs without respiratory signs

This study aimed to prospectively assess nasopharyngeal luminal changes in brachycephalic dogs without respiratory signs using cervical radiography. Forty brachycephalic dogs without cardiopulmonary diseases were included. The nasopharyngeal luminal change was calculated on inspiratory and expiratory cervical lateral radiographs. The median nasopharyngeal luminal change was 21.6% (range, 0.3-85.6%). In five dogs, a nasopharyngeal luminal change of >50% was identified. There was no correlation between nasopharyngeal luminal changes and age, sex, body weight, or body condition score. These results suggest that brachycephalic dogs without cardiopulmonary diseases may be over-diagnosed with partial pharyngeal collapse. Further studies comparing nasopharyngeal luminal changes between clinically healthy brachycephalic dogs and dogs with respiratory signs are warranted.

Automatic scoring of drug-induced sleep endoscopy for obstructive sleep apnea using deep learning

BACKGROUND

Treatment of obstructive sleep apnea is crucial for long term health and reduced economic burden. For those considered for surgery, drug-induced sleep endoscopy (DISE) is a method to characterize location and pattern of sleep-related upper airway collapse. According to the VOTE classification system, four upper airway sites of collapse are characterized: velum (V), oropharynx (O), tongue (T), and epiglottis (E). The degree of obstruction per site is classified as 0 (no obstruction), 1 (partial obstruction), or 2 (complete obstruction). Here we propose a deep learning approach for automatic scoring of VOTE obstruction degrees from DISE videos.

METHODS

We included 281 DISE videos with varying durations (6 s-16 min) from two sleep clinics: Copenhagen University Hospital and Stanford University Hospital. Examinations were split into 5-s clips, each receiving annotations of 0, 1, 2, or X (site not visible) for each site (V, O, T, and E), which was used to train a deep learning model. Predicted VOTE obstruction degrees per examination was obtained by taking the highest predicted degree per site across 5-s clips, which was evaluated against VOTE degrees annotated by surgeons.

RESULTS

Mean F1 score of 70% was obtained across all DISE examinations (V: 85%, O: 72%, T: 57%, E: 65%). For each site, sensitivity was highest for degree 2 and lowest for degree 0. No bias in performance was observed between videos from different clinicians/hospitals.

CONCLUSIONS

This study demonstrates that automating scoring of DISE examinations show high validity and feasibility in degree of upper airway collapse.

The HIF1α polymorphism rs2301104 is associated with obesity and obesity-related cytokines in Han Chinese population

AIMS

To evaluate the association between genetic polymorphisms of HIF1α and obesity and obesity-related cytokines in the Han Chinese population.

METHODS

The study consisted of 160 subjects with obesity and 166 age- and gender-matched healthy controls. We genotyped three tag single nucleotide polymorphisms (SNPs) of HIF1α by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based genotyping technology. Plasma cytokine concentrations were determined on the Luminex platform. The genetic associations were analysed statistically.

RESULTS

Obese subjects had significant obesity-related metabolic abnormalities, including hyperglycaemia, insulin resistance, and abnormalities in blood lipids, liver enzymes, and uric acid levels. SNP analysis of HIF1α revealed that the allele and genotype frequencies of rs2301104 were significantly associated with obesity. Our results suggest that the minor allele C of rs2301104 might be a protective mutation of obesity, and CC/CG genotypes of rs2301104 could be protective genotype of obesity. We also found that subjects with CC/CG genotypes of rs2301104 had significantly lower levels of IL-6, TNF-α, IL-1β, IL-8, and IL-10 than subjects with GG genotypes.

CONCLUSIONS

This is the first study to report an association between HIF1α polymorphisms and obesity and obesity-related cytokines in a Han Chinese population. These results require replication in larger populations but suggest that HIF1α may play an important role in obesity development.

Ambient Air Pollution Exposure and Sleep Quality in COPD

Rationale

Ambient air pollution exposure is associated with respiratory morbidity among individuals with chronic obstructive pulmonary disease (COPD), particularly among those with concomitant obesity. Although people with COPD report high incidence of poor sleep quality, no studies have evaluated the association between air pollution exposure, obesity, and sleep disturbances in COPD.

Methods

We analyzed data collected from current and former smokers with COPD enrolled in the Subpopulations and Intermediate Outcome Measures in COPD -Air Pollution ancillary study (SPIROMICS AIR). Socio-demographics and anthropometric measurements were collected, and 1-year mean historical ambient particulate matter (PM2.5) and ozone concentrations at participants' residences were estimated by cohort-specific spatiotemporal modeling. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI), and regression models were constructed to determine the association of 1-year PM2.5 (1Yr-PM2.5) and 1-year ozone (1Yr-ozone) with the PSQI score, and whether obesity modified the association.

Results

In 1308 participants (age: 65.8±7.8 years, 42% women), results of regression analyses suggest that each 10µg/m3 increase in 1Yr-PM2.5 was associated with a 2.1-point increase in PSQI (P=0.03). Obesity modified the association between 1Yr-PM2.5 and PSQI (P=0.03). In obese and overweight participants, a 10µg/m3 increase in 1Yr-PM2.5 was associated with a higher PSQI (4.0 points, P<0.01, and 3.4 points, P<0.01, respectively); but no association in lean-normal weight participants (P=0.51). There was no association between 1 Yr-ozone and PSQI.

Conclusions

Overweight and obese individuals with COPD appear to be susceptible to the effects of ambient PM2.5 on sleep quality. In COPD, weight and ambient PM2.5 may be modifiable risk factors to improve sleep quality.

Gasotransmitter modulation of hypoglossal motoneuron activity

Obstructive sleep apnea (OSA) is characterized by sporadic collapse of the upper airway leading to periodic disruptions in breathing. Upper airway patency is governed by genioglossal nerve activity that originates from the hypoglossal motor nucleus. Mice with targeted deletion of the gene Hmox2, encoding the carbon monoxide (CO) producing enzyme, heme oxygenase-2 (HO-2), exhibit OSA, yet the contribution of central HO-2 dysregulation to the phenomenon is unknown. Using the rhythmic brainstem slice preparation that contains the preBötzinger complex (preBötC) and the hypoglossal nucleus, we tested the hypothesis that central HO-2 dysregulation weakens hypoglossal motoneuron output. Disrupting HO-2 activity increased the occurrence of subnetwork activity from the preBötC, which was associated with an increased irregularity of rhythmogenesis. These phenomena were also associated with the intermittent inability of the preBötC rhythm to drive output from the hypoglossal nucleus (i.e. transmission failures), and a reduction in the input-output relationship between the preBötC and the motor nucleus. HO-2 dysregulation reduced excitatory synaptic currents and intrinsic excitability in inspiratory hypoglossal neurons. Inhibiting activity of the CO-regulated H2S producing enzyme, cystathionine-γ-lyase (CSE), reduced transmission failures in HO-2 null brainstem slices, which also normalized excitatory synaptic currents and intrinsic excitability of hypoglossal motoneurons. These findings demonstrate a hitherto uncharacterized modulation of hypoglossal activity through mutual interaction of HO-2/CO and CSE/H2S, and support the potential importance of centrally derived gasotransmitter activity in regulating upper airway control.

Endocrine disorders in obstructive sleep apnoea syndrome: A bidirectional relationship

Obstructive sleep apnoea (OSA) is a common disorder characterized by recurrent episodes of apnoea or hypopnea due to total or partial pharyngeal collapse and temporary upper airway obstruction during sleep. The prevalence of OSA is increasing and currently affects about 30% of men and 13% of women in Europe. Intermittent hypoxia, oxidative stress, systemic inflammation, and sleep fragmentation resulting from OSA can provoke subsequent cardiometabolic disorders. The relationships between endocrine disorders and OSA are complex and bidirectional. Indeed, several endocrine disorders are risk factors for OSA. Compared with the general population, the prevalence of OSA is increased in patients with obesity, hypothyroidism, acromegaly, Cushing syndrome, and type 1 and 2 diabetes. In some cases, treatment of the underlying endocrine disorder can improve, and occasionally cure, OSA. On the other hand, OSA can also induce endocrine disorders, particularly glucose metabolism abnormalities. Whether continuous positive airway pressure (CPAP) treatment for OSA can improve these endocrine disturbances remains unclear due to the presence of several confounding factors. In this review, we discuss the current state-of-the-art based on the review of the current medical literature for key articles focusing on the bidirectional relationship between endocrine disorders and OSA and the effects of treatment. Screening of OSA in endocrine patients is also discussed, as it remains a subject of debate.

Association of physical activity and heart rate variability in people with overweight and obesity: A systematic review

Background: Obesity is a major public health issue globally which is intrinsically linked to reduced heart rate variability (HRV). Physical inactivity and reduced resting HRV are linked to an increased risk of coronary heart disease, while athletes have a greater HRV. However, the exact correlation between physical activity and HRV remains uncertain. This systematic review aims to collect, report, and critically assess the current scientific literature about the association between physical activity and HRV in individuals with higher weight and obesity. Methods: A systematic search was carried out in electronic databases (Medline/PubMed, SCOPUS and CINAHL Plus) to retrieve studies that evaluated the relationship between physical activity and HRV in individuals with higher weight and obesity. Case-control, longitudinal/cohort, cross-sectional and observational studies were included. Using a critical narrative approach, information about the HRV, and physical activity was extracted and synthesized. The study was registered in PROSPERO: CRD42020208018 on October 9 2020. Results: After removing duplicates, 980 title/abstract records were checked for eligibility, and 12 papers were finally included in the narrative synthesis. The included studies contained physical activity as well as HRV in adults with higher weight or obesity with or without comorbidities. A negative relationship between moderate to vigorous physical activity and HRV indices had been found in two studies. There was also a negative relationship between sedentary time and HF (p = 0.049) and LF/HF (p = 0.036), as well as a positive relationship between sedentary time and LF (p = 0.014). Also dose-response association was found between vigorous exercise and higher SDNN, LF power, and HF power in one of the studies. Conclusions: This systematic review revealed a wide range of responses to physical activity and HRV; however, the current evidence uses a variety of approaches to objectively assess physical activity and measure HRV with different equipment.

Personalized Medicine and Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a common disease that is often under-diagnosed and under-treated in all ages. This is due to differences in morphology, diversity in clinical phenotypes, and differences in diagnosis and treatment of OSA in children and adults, even among individuals of the same age. Therefore, a personalized medicine approach to diagnosis and treatment of OSA is necessary for physicians in clinical practice. In children and adults without serious underlying medical conditions, polysomnography at sleep labs may be an inappropriate and inconvenient testing modality compared to home sleep apnea testing. In addition, the apnea-hypopnea index should not be considered as a single parameter for making treatment decisions. Thus, the treatment of OSA should be personalized and based on individual tolerance to sleep-quality-related parameters measured by the microarousal index, harmful effects of OSA on the cardiovascular system related to severe hypoxia, and patients' comorbidities. The current treatment options for OSA include lifestyle modification, continuous positive airway pressure (CPAP) therapy, oral appliance, surgery, and other alternative treatments. CPAP therapy has been recommended as a cornerstone treatment for moderate-to-severe OSA in adults. However, not all patients can afford or tolerate CPAP therapy. This narrative review seeks to describe the current concepts and relevant approaches towards personalized management of patients with OSA, according to pathophysiology, cluster analysis of clinical characteristics, adequate combined therapy, and the consideration of patients' expectations.

Obesity Pillars Roundtable: Body mass index and body composition in Black and Female individuals. Race-relevant or racist? Sex-relevant or sexist?

Background

Body mass index (BMI or weight in kilograms/height in meters2) is the most common metric to diagnose overweight and obesity. However, a body composition analysis more thoroughly assesses adiposity, percent body fat, lean body mass (i.e., including skeletal muscle), and sometimes bone mineral density. BMI is not an accurate assessment of body fat in individuals with increased or decreased muscle mass; the diagnostic utility of BMI in individuals is also influenced by race and sex.

Methods

Previous Obesity Pillars Roundtables addressed the diagnostic limitations of BMI, the importance of android and visceral fat (especially among those with South and East Asian ancestry), and considerations of obesity among individuals who identify as Hispanic, diverse in sexual-orientation, Black, Native American, and having ancestry from the Mediterranean and Middle East regions. This roundtable examines considerations of BMI in Black and female individuals.

Results

The panelists agreed that body composition assessment was a more accurate measure of adiposity and muscle mass than BMI. When it came to matters of race and sex, one panelist felt: "race is a social construct and not a defining biology." Another felt that: "BMI should be a screening tool to prompt further evaluation of adiposity that utilizes better diagnostic tools for body composition." Regarding bias and misperceptions of resistance training in female individuals, another panelist stated: "I have spent my entire medical career taking care of women and have never seen a woman unintentionally gain 'too much' muscle mass and bulk up from moderate strength training."

Conclusions

Conveying the importance of race and sex regarding body composition has proven challenging, with the discussion sometimes devolving into misunderstandings or misinformation that may be perceived as racist or sexist. Body composition analysis is the ultimate diagnostic equalizer in addressing the inaccuracies and biases inherent in the exclusive use of BMI.

Volume of parapharyngeal fat pad in obstructive sleep apnea syndrome: prognostic role for multilevel sleep surgery

STUDY OBJECTIVES

To evaluate the prognostic role of volume of parapharyngeal fat pad (VPPFP) after multilevel sleep surgery in patients with obstructive sleep apnea syndrome.

METHODS

This retrospective cohort study was conducted in 50 patients with moderate to severe obstructive sleep apnea syndrome who underwent polysomnography (preoperative and postoperative 6 months) and preoperative facial computed tomography with multilevel sleep surgery between May 2010 and February 2019. All patients had failed or refused positive airway pressure treatment.

RESULTS

Of the 50 patients with moderate to severe obstructive sleep apnea syndrome who underwent multilevel sleep surgery, 46 were male (92.0%) with mean ± standard deviation age of 41.2 ± 12.5 years. On the preoperative polysomnography, mean ± standard deviation of apnea-hypopnea index and CT90 (cumulative percentage of time spent at oxygen saturation less than 90%) were 43.4 ± 19.3 events/h and 5.6 ± 9.6%, respectively. The average VPPFP measured by facial computed tomography scan was 4.9 ± 1.9 cm3. Multiple linear regression analysis showed that VPPFP was significantly correlated (R2 = 0.38) with age (β = 0.05; 95% confidence interval [CI], 0.01-0.09) and body mass index (β = 0.31; 95% CI, 0.16-0.45). Surgical success rate was 38%, and VPPFP higher than 5.1 cm3 was significantly associated with surgical failure after covariate adjustment (P = .01; odds ratio = 0.09; 95% CI, 0.02-0.48). Postoperative apnea-hypopnea index was positively correlated (R2 = 0.40) with CT90 (β = 1.33; 95% CI, 0.74-1.92) and VPPFP (β = 3.52; 95% CI, 0.30-6.74).

CONCLUSIONS

VPPFP correlated with age and body mass index, and high VPPFP and CT90 were associated with high postoperative apnea-hypopnea index. VPPFP larger than 5.1 cm3 was a possible risk factor for surgical failure, which may inform a decision on multilevel sleep surgery as salvage therapy for positive airway pressure treatment.

CITATION

Kim BK, Park SI, Hong SD, Jung YG, Kim HY. Volume of parapharyngeal fat pad in obstructive sleep apnea syndrome: prognostic role for multilevel sleep surgery. J Clin Sleep Med. 2022;18(12):2819-2828.

Trends in the prevalence of metabolically healthy and unhealthy obesity in the US adult population: analysis of eight NHANES cross-sectional survey cycles, 1999-2014

OBJECTIVE

To exam the time trend of the prevalence of metabolically healthy obesity (MHO) in the US adult population.

DESIGN

Eight cross-sectional survey cycles.

SETTING

National Health and Nutrition Examination Survey (NHANES), 1999-2014.

PARTICIPANTS

16 459 NHANES participants aged 20 years and older.

PRIMARY OUTCOME MEASURE

MHO was defined as central obesity (waist circumference ≥102 cm for men and ≥88 cm for women) without any of the following conditions: elevated levels of blood pressure (≥130/85 mm Hg), glucose (≥100 mg/dL) and triglycerides (≥150 mm/dL); reduced levels of high-density lipoprotein cholesterol (<40 mg/dL for men and <50 mg/dL for women) or any medication use for high cholesterol, hypertension or diabetes.

RESULTS

The prevalence of central obesity significantly increased from 45.2% in 1999-2000 to 56.7% in 2013-2014 (p=0.003). Over the same period, MHO prevalence among those with central obesity only slightly and non-significantly increased from 11.0% to 15.7% (p=0.38). However, MHO prevalence among women increased significantly (p=0.04) from 7.1% to 13.7%. Female gender, a younger age, being Hispanic and non-Hispanic black and high education (some college or above) were significantly (p<0.05) associated with higher prevalence of MHO.

CONCLUSIONS

While the prevalence of central obesity in the US population has increased since 1999, the prevalence of MHO among those who are centrally obese remained fairly stable.

Relationship between lipids and sleep apnea: Mendelian randomization analysis

BACKGROUND

Lipids increase the risk of sleep apnea; however, the causality between them is still inconclusive.

AIM

To explore the causal relationship between serum lipids and sleep apnea using two-sample Mendelian randomization (MR) analysis.

METHODS

Single nucleotide polymorphism (SNP) data related to serum lipids were obtained from the Global Lipids Genetics Consortium study, which included 188578 individuals of European ancestry. Additionally, sleep apnea-related SNP data were collected from the United Kingdom Biobank study, which comprised 463005 individuals of European ancestry. Two-sample MR analysis was performed to assess the causality between serum lipids and sleep apnea based on the above public data.

RESULTS

Genetically predicted low-density lipoprotein (odds ratio [OR] = 0.99, 95% confidence interval [CI] = 0.99 to 1.00; P = 0.58), high-density lipoprotein (OR = 0.99, 95%CI = 0.99 to 1.00; P = 0.91), triglyceride (OR = 1.00, 95%CI = 0.99 to 1.00; P = 0.92), and total cholesterol (OR = 0.99, 95%CI = 0.99 to 1.00; P = 0.33) were causally unrelated to sleep apnea.

CONCLUSION

Our MR analysis suggests that genetically predicted serum lipids are not risk factors of sleep apnea.