Association between Obstructive Sleep Apnea and Type 2 Diabetes Mellitus: A Dose-Response Meta-Analysis

[Relationship between obstructive sleep apnea and type 2 diabetes mellitus]

INTRODUCTION

The association between obstructive sleep apnea (OSA) and glucose metabolism remains controversial. This study investigates the relationship between OSA and incident type 2 diabetes (DM) and prediabetes (preDM), as well as the effect of long-term CPAP (continuous positive airway pressure) treatment.

METHODS

Follow-up study in a retrospective clinical cohort of patients with OSA and randomly selected controls. Data on incident DM and preDM as well as CPAP were obtained from hospital records. The relationship between baseline OSA and incident DM was examined using COX regression models.

RESULTS

Three hundred and fifty-six patients, 169 with OSA and 187 controls were followed for a median of 98 months; 47 patients (13.2%) developed DM and 43 (12.1%) developed preDM. The 5-year cumulative incidence of DM was 10.7% (6.5-13.9%). 87% of subjects with preDM in the baseline sample progressed to incident DM. It is shown that body mass index (BMI), nocturnal hypoxia and apnea hypopnea index (AHI) are risk factors for the development of DM and that CPAP reduces this risk.

CONCLUSIONS

Patients with OSA have a higher risk of developing DM. The risk factors involved are BMI, nocturnal hypoxia and AHI. Regular long-term CPAP use was associated with a decreased risk.

[Diabetes and obstructive sleep apnoea: A case-control study]

INTRODUCTION

Obstructive sleep apnoea (OSA) and diabetes mellitus (DM) are very prevalent diseases frequently associated. Their coexistence is independently associated with an increased prevalence of cardiovascular comorbidities. As this association is underdiagnosed, it is necessary to optimise clinical suspicion by studying independent predictors of DM or prediabetes (preDM) in patients with OSA.

METHOD

A simple randomised case-control study, matched for sex, body mass index (BMI) and age, aimed to study the association of OSA with DM and preDM and to identify independent predictors for both diseases in people with OSA.

RESULTS

We included 208 cases with OSA and 208 controls without OSA. In the former, 18.8% had DM compared to only 10.1% in the latter (P=.00). Prevalence of preDM was 41.8% vs. 10.6%, respectively (P=.00). One hundred and twenty-four cases (59.6%) reported excessive daytime sleepiness (EDS) (Epworth scale, 10.5±3.1) vs. 24.5% of the control group (Epworth scale, 6.6±2.9). Apnoea-hypopnoea index (AHI) and O2 desaturation indices (IDO, CT90 and CT80) were significantly higher in the case group. The risk of MD was related to age, nocturnal hypoxaemia and EDS. The risk of pre-MD was related to BMI and AHI.

CONCLUSIONS

OSA is associated with DM and preDM. Age, nocturnal hypoxaemia and EDS are predictors of DM. BMI and AHI are predictors of pre-MD.

Sleep and cardiovascular disease

This review centres around the recent evidence in examining the intersection of sleep and cardiovascular disease (CVD). Sleep in this review will be further subdivided to consider both sleep quantity and quality along and will also consider some of the more common sleep disorders, such as insomnia and obstructive sleep apnoea, in the context of CVD. Sleep disorders have been further explored in several specific populations which are both at risk of sleep disorders and CVD. Secondly, the review will present some of the risk factors for CVD that are affected by sleep and sleep disorders which include hypertension, diabetes, and obesity. It will also examine the potential underlying mechanisms including inflammation, appetite control, endocrine, and genetic processes that are affected by sleep and sleep disorders leading to increased risk of CVD development. In addition, we will consider the observed bi-directional relationships between sleep and cardiovascular risk factors. For example, obesity, a risk factor for CVD can be affected by sleep, but in turn can increase the risk of certain sleep disorder development which disrupts sleep, leading to further risk of obesity development and increased CVD risk. Finally, the review will explore emerging evidence around lifestyle interventions that have included a sleep component and how it impacts the management of CVD risk factor. The need for increased awareness of the health effects of poor sleep and sleep disorders will be discussed alongside the need for policy intervention to improve sleep to facilitate better health and well-being.

Genetic association between coffee/caffeine consumption and the risk of obstructive sleep apnea in the European population: a two-sample Mendelian randomization study

BACKGROUND

The association between coffee/caffeine consumption and obstructive sleep apnea (OSA) risk remains unclear.

PURPOSE

To determine the relationship between coffee/caffeine consumption and the risk of OSA, using the Mendelian randomization (MR) method in the European population.

METHODS

Two sets of coffee consumption-associated genetic variants were, respectively, extracted from the recent genome-wide meta-analysis (GWMA) and genome-wide association study (GWAS) of coffee consumption. Taking other caffeine sources into account, genetic variants associated with caffeine consumption from tea and plasma caffeine (reflecting total caffeine intake) were also obtained. The inverse variance weighted (IVW) technique was utilized as the primary analysis, supplemented by the MR-Egger, weighted-median, and MR-Pleiotropy RESidual Sum and Outlier (PRESSO) techniques. Leave-one-out (LOO) analysis was performed to assess whether the overall casual estimates were driven by a single SNP. Additional sensitivity analyses were performed using similar methods, while the genetic variants associated with confounders, e.g., body mass index and hypertension, were excluded.

RESULTS

The IVW method demonstrated that coffee consumption GWMA (OR: 1.065, 95% CI 0.927-1.224, p = 0.376), coffee consumption GWAS (OR: 1.665, 95% CI 0.932-2.977, p = 0.086), caffeine from tea (OR: 1.198, 95% CI 0.936-1.534, p = 0.151), and blood caffeine levels (OR: 1.054, 95% CI 0.902-1.231, p = 0.508) were unlikely to be associated with the risk of OSA. The other three methods presented similar results, where no significant associations were found. No single genetic variant was driving the overall estimates by the LOO analysis. These findings were also supported by the sensitivity analyses with no confounding genetic variants.

CONCLUSION

Our study found no association between coffee/caffeine consumption and the risk of OSA.

Redefining Comorbid Insomnia and Sleep Apnea: The Association of Sleep Breathing Impairment and Insomnia with Incident Diabetes

Rationale: Obstructive sleep apnea (OSA) is a prevalent sleep disorder that is frequently comorbid with insomnia and often accompanied by metabolic diseases such as type 2 diabetes. Although the apnea-hypopnea index (AHI) is currently the diagnostic criterion for gauging the severity of OSA, the AHI has not consistently predicted incident diabetes. Objectives: To test whether a combined insomnia-OSA (COMISA) phenotype based on comorbid insomnia and sleep breathing impairment index (COMISA-SBII) predicts incident diabetes and to compare the association with an AHI definition of COMISA (COMISA-AHI) in the MrOS (Osteoporotic Fractures in Men) study. Methods: The study samples came from participants in the MrOS sleep study without diabetes at their baseline examination. The SBII was derived as the product of the duration of each respiratory event (apnea and hypopnea) and the accompanying desaturation area from baseline unattended polysomnography. A subgroup of individuals classified as having comorbid insomnia (difficulties falling asleep, waking up in the middle of the night and/or early morning awakenings >15 times per month, and daytime impairments) and sleep breathing impairment (greater than 50th percentile of SBII) were identified at baseline. The primary outcome was incident diabetes during the follow-up visits. Cox proportional models were built to assess the adjusted hazard ratios of COMISA-AHI and COMISA-SBII. Prediction model performances of incident diabetes were compared across different models. Results: A total of 2,365 men (mean age, 76 yr) without diabetes at baseline were included. During a median follow-up of 10.0 years, diabetes developed in 181. After adjusting for demographic characteristics, comorbidities, and behavioral risk factors, participants with COMISA-SBII had a higher risk of incident diabetes (hazard ratio, 1.82; 95% confidence interval, 1.15-2.89) than those without sleep disorders (those with an SBII ⩽13.17 and no insomnia). The result remained significant in the risk competing model. Compared with COMISA-AHI, the addition of COMISA-SBII to a crude model with established risk factors significantly improved the predictive value of incident diabetes. Conclusions: COMISA-SBII, but not COMISA-AHI, predicted incident diabetes after accounting for multiple covariates in a cohort of older men. A comorbid insomnia phenotype based on SBII plus insomnia symptoms may be an important clinical subtype.

Global Prevalence of Obstructive Sleep Apnea in the Elderly and Related Factors: A Systematic Review and Meta-Analysis Study

PURPOSE

The aims of current meta-analysis was to combine data and statistics on the global prevalence of OSA and related factors in older adults.

DESIGN

A systematic review and meta-analysis.

METHODS

To find related studies, various databases were searched including Embase, PubMed, Scopus, Web of Science (WoS), MagIran, and SID (two local databases) using appropriate keywords, MeSH and controlled vocabulary, with no time limitation up to June, 2021. Heterogeneity of studies was evaluated using I2, and Egger's regression intercept was used to detect publication bias.

FINDINGS

39 studies with a total sample size of 33,353 people were included. The pooled prevalence of OSA in older adults was 35.9% (95% confidence interval: 28.7%-43.8%; I2 = 98.81%). Considering the high heterogeneity of included studies, subgroup analysis was conducted and yielded the most prevalent in Asia continent with 37.0% (95% CI: 22.4%-54.5%; I2 = 97.32%). However, heterogeneity was remained at high level. In the majority of studies, OSA was significantly and positively related to obesity, increased BMI, age, cardiovascular diseases, diabetes, and daytime sleepiness.

CONCLUSIONS

Results of this study showed that global prevalence of OSA in older adults is high and is significantly related to obesity, increased BMI, age, cardiovascular diseases, diabetes, and daytime sleepiness. These findings can be used by experts working on the diagnosis and management of OSA in the geriatric population. These findings can be used by experts on the diagnosis and treatment of OSA in the older adults. Due to high heterogeneity, findings should be interpreted with great caution.

Characterization of sleep apnea among a sample of adults from Samoa

Sleep apnea is a public health concern around the world, but little research has been dedicated to examining this issue in low- and middle-income countries, including Samoa. Using data collected through the Soifua Manuia ("Good Health") study, which aimed to investigate the impact of the body mass index (BMI)-associated genetic variant rs373863828 in CREB3 Regulatory Factor ( CREBRF ) on metabolic traits in Samoan adults, we examined the sample prevalence and characteristics of sleep apnea using data collected with a validated home sleep apnea device (WatchPAT, Itamar). A total of 330 participants (sampled to overrepresent the obesity-risk allele of interest) had sleep data available. Participants (53.3% female) had a mean (SD) age of 52.0 (9.9) years and BMI of 35.5 (7.5) kg/m 2 and 36.3% of the sample had type 2 diabetes. Based on the 3% and 4% apnea hypopnea indices (AHI) and the 4% oxygen desaturation index (ODI), descriptive analyses revealed that many participants had potentially actionable sleep apnea defined as >5 events/hr (87.9%, 68.5%, and 71.2%, respectively) or clinically actionable sleep apnea defined as ≥15 events/hr (54.9%, 31.5%, and 34.5%, respectively). Sleep apnea was more severe in men; for example, clinically actionable sleep apnea (≥15) based on the AHI 3% definition was observed in 61.7% of men and 48.9% of women. Correction for non-representational sampling related to the CREBRF obesity-risk allele resulted in only slightly lower estimates. Across the AHI 3%, AHI 4%, and ODI 4%, multiple linear regression revealed associations between a greater number of events/hr and higher age, male sex, higher body mass index, higher abdominal-hip circumference ratio, and geographic region of residence. Our study identified a much higher frequency of sleep apnea in Samoa compared with published data from other studies, but similar predictors. Continued research addressing generalizability of these findings, as well as a specific focus on diagnosis and affordable and equitable access to treatment, is needed to alleviate the burden of sleep apnea in Samoa and around the world.

Shorter respiratory event duration is related to prevalence of type 2 diabetes

BACKGROUND

Obstructive sleep apnea (OSA) is a heterogeneous sleep disorder often comorbid with metabolic diseases, and type 2 diabetes (T2DM) is one of them. Although apnea hypopnea index (AHI) is currently the diagnostic criteria for OSA severity, a controversial relationship between AHI and T2DM has been found. On the other hand, the duration of apnea-hypopnea events has been shown to be a useful metric for predicting mortality. This study aimed to test whether average respiratory event duration was associated with prevalence of T2DM.

METHODS

Patients referred to the sleep clinic were recruited in the study. Baseline clinical characteristics and polysomnography parameters including average respiratory event duration were collected. The association of average respiratory event duration with the prevalence of T2DM was evaluated by univariate and multivariate logistic regression analyses.

RESULTS

A total of 260 participants were enrolled, and 92 (35.4%) had T2DM. Univariate analysis revealed that age, body mass index (BMI), total sleep time, sleep efficiency, history of hypertension, and shorter average respiratory event duration were associated with T2DM. In multivariate analysis, only age and BMI remained significant. While average respiratory event duration was insignificant in multivariate analysis, subtype event analysis showed that shorter average apnea duration was both significant in univariate (OR, 0.95; 95% CI, 0.92-0.98) and multivariate analyses (OR, 0.95; 95% CI, 0.91-0.99). Neither average hypopnea duration nor AHI was associated with T2DM. Significant association (OR, 1.19; 95% CI, 1.12-1.25) was observed between shorter average apnea duration and lower respiratory arousal threshold after multivariate adjustment. However, causal mediation analysis revealed no mediating effect of arousal threshold on average apnea duration and T2DM.

CONCLUSION

The average apnea duration may be a useful metric in the diagnosis of OSA comorbidity. Shorter average apnea duration indicating poor sleep quality and augmented autonomic nervous system responses might be the potential pathological mechanisms leading to T2DM.

The role of ferroptosis in chronic intermittent hypoxia-induced lung injury

PURPOSE

Chronic intermittent hypoxia (CIH) causes lung injury but the mechanism is unclear. Ferroptosis is a novel form of programmed cell death. In this research, we attempted to explore the role of ferroptosis in CIH-induced lung injury both in vitro and in vivo.

METHODS

Sprague-Dawley rats were randomly separated into control group, CIH group and CIH + ferrostatin-1 group (CIH + Fer-1). Rats in the CIH group and CIH + Fer-1 group were exposed to intermittent hypoxia for 12 weeks. Human bronchial epithelial cell line (BEAS-2B) was cultivated for 24 h in either conventional culture medium or under CIH conditions. Fer-1 was applied to observe its treatment effects. Histological changes were evaluated by Hematoxylin-eosin (HE) staining and masson staining. The expression levels of Acyl-CoA synthetase long-chain family member 4 (ACSL4), glutathione peroxidase 4 (GPX4), interleukin-6 (IL-6) and tumour necrosis factor α (TNFα) were detected via qRT-PCR or Western blot. Cell counting kit-8 (CCK-8) was used to assess cell viability. The apoptotic rate and reactive oxygen species (ROS) was calculated by flow cytometry.

RESULTS

Histology showed that CIH treatment induced lung injury and pulmonary fibrosis in lung tissue. After Fer-1 treatment, the pathological changes caused by CIH alleviated. The mRNA and protein levels of GPX4 decreased significantly in lung tissues of CIH-treated rats and BEAS-2B, (p < 0.05). The mRNA and protein levels of ACSL4 increased significantly in lung tissues of CIH-treated rats and BEAS-2B, (p < 0.05). The mRNA levels of IL-6 and TNFα in BEAS-2B increased after CIH treatment, (p < 0.05). Cell viability decreased, apoptosis rate and ROS increased in CIH-treated BEAS-2B, (p < 0.05). Cotreatment with Fer-1 reversed CIH-induced apoptosis, cell viability, ROS accumulation, mRNA and protein levels of GPX4, ACSL4, IL-6 and TNFα both in vitro and in vivo (p < 0.05).

CONCLUSIONS

Ferroptosis occurred in CIH-induced lung injury, both in vitro and in vivo. The ferroptosis inhibitor Fer-1 alleviated cell injury and ferroptosis in CIH-treated BEAS-2B and lung tissues of rats.

Sleep Apnea and Cardiovascular Risk in Patients with Prediabetes and Type 2 Diabetes

Obstructive sleep apnea (OSA) is a common but largely undiagnosed clinical condition, which is turning into a serious public health issue. Of note is that its prevalence is gradually increasing in parallel with the obesity and type 2 diabetes mellitus (T2DM) epidemics. The aim of this article is to comprehensively review the literature in order to evaluate the cardiovascular (CV) risk among patients with OSA and prediabetes or T2DM. OSA seems to be an independent risk factor for the development as well as the progression of T2DM, whereas it is associated with T2DM-related macrovascular and microvascular complications. OSA may also act as a potential risk factor for the presentation and development of CV disease, such as hypertension, coronary artery disease, heart failure, pulmonary hypertension, atrial fibrillation and other cardiac arrythmias, as well as stroke. OSA and T2DM also share common pathophysiological mechanisms leading to atherosclerosis. Considering that the coexistence of OSA and T2DM is an independent and cumulative risk factor for CV mortality, more so than the two diseases separately, clinicians and healthcare professionals should be aware of and screen for OSA in patients with T2DM. Notably, targeted therapy for both conditions seems to substantially improve CV prognosis.

Type 2 diabetes

Type 2 diabetes accounts for nearly 90% of the approximately 537 million cases of diabetes worldwide. The number affected is increasing rapidly with alarming trends in children and young adults (up to age 40 years). Early detection and proactive management are crucial for prevention and mitigation of microvascular and macrovascular complications and mortality burden. Access to novel therapies improves person-centred outcomes beyond glycaemic control. Precision medicine, including multiomics and pharmacogenomics, hold promise to enhance understanding of disease heterogeneity, leading to targeted therapies. Technology might improve outcomes, but its potential is yet to be realised. Despite advances, substantial barriers to changing the course of the epidemic remain. This Seminar offers a clinically focused review of the recent developments in type 2 diabetes care including controversies and future directions.

The critical issue linking lipids and inflammation: Clinical utility of stopping oxidative stress

The formation of an atheroma begins when lipoproteins become trapped in the intima. Entrapped lipoproteins become oxidized and activate the innate immune system. This immunity represents the primary association between lipids and inflammation. When the trapping continues, the link between lipids and inflammation becomes chronic and detrimental, resulting in atherosclerosis. When entrapment ceases, the association between lipids and inflammation is temporary and healthy, and the atherogenic process halts. Therefore, the link between lipids and inflammation depends upon lipoprotein retention in the intima. The entrapment is due to electrostatic forces uniting apolipoprotein B to polysaccharide chains on intimal proteoglycans. The genetic transformation of contractile smooth muscle cells in the media into migratory secretory smooth muscle cells produces the intimal proteoglycans. The protein, platelet-derived growth factor produced by activated platelets, is the primary stimulus for this genetic change. Oxidative stress is the main stimulus to activate platelets. Therefore, minimizing oxidative stress would significantly reduce the retention of lipoproteins. Less entrapment decreases the association between lipids and inflammation. More importantly, it would halt atherogenesis. This review will analyze oxidative stress as the critical link between lipids, inflammation, and the pathogenesis of atherosclerosis. Through this perspective, we will discuss stopping oxidative stress to disrupt a harmful association between lipids and inflammation. Numerous therapeutic options will be discussed to mitigate oxidative stress. This paper will add a new meaning to the Morse code distress signal SOS-stopping oxidative stress.

Identification of Gene Coexpression Modules and Prognostic Genes Associated with Papillary Thyroid Cancer

Thyroid cancer is a great part of the endocrine tumor with an increasing incidence. Papillary thyroid carcinoma (PTC) is the most common subtype. With the enormous pace taken in the microarray technology, bioinformatics is applied in data mining more frequently. Weighted gene coexpression network analysis (WGCNA) can perform analysis combining clinic information. We performed WGCNA for prognostic genes associated with PTC. From the GEO profile, we got ten modules. We identified a key module that was closest to patients’ survival time. Then, we screened five hub genes (ATRX, BOD1L1, CEP290, DCAF16, and NEK1) from the key module based on the clinical information from TCGA. These five genes not only significantly differ between the normal and tumor groups but have prognostic value. The receiver operating characteristic (ROC) curve indicated that they had the potential to serve as prognostic genes. We performed next-generation sequencing using the PTC tissue to get more convincing evidence. Besides, we established a new signature and verified it through K-M plots and ROC. The signature could be an independent factor for the prognosis of PTC, and we built a nomogram to carry out a quantitative study. In a word, the hub genes we explored in the study deserved more basic and clinical research.

X-Ray Cephalometric Analysis of the Effects of Angle Class II and III Malocclusion on the Upper Airway Width and Hyoid Position between Parents and Children of Uygur Nationality

Objective

The objective of this paper is to analyze the effect of angle class II and III malocclusion on the sagittal diameter of the upper airway between parents and children of Uygur nationality and to compare the degree of influence.

Methods

29 Uygur adolescents with malocclusion and their fathers (mothers) were selected as our subjects via X-ray cephalometric radiograph to analyze the difference between the upper airway sagittal dimension and normal occlusion and compare the influence of malocclusion on the upper airway between parents and children.

Results

Compared with normal group, the vertical distance from the hyoid point to orbital-ear plane (H-FH) and vertical distance from hyoid point to the mandibular plane (H-MP) in angle class II malocclusion elevated signally, while the vertical distance from hyoid point to anterior cervical plane (H-VL), PNS-UPW, H-FH, and H-MP decreased significantly; compared with normal group: the distance between the posterior nasal spine and the upper pharynx wall (PNS-UPW), H-FH, and H-MP in angle class III malocclusion visually reduced, while PAS, and horizontal distance from the hyoid point and center point of sella turcica to orbital-ear foot (H-S), increased markedly. The impact of class II malocclusion on parents' U-MPM was greater than their children.

Conclusion

The oropharyngeal space of upper airway becomes smaller and hyoid shifts downwards due to class II malocclusion. Class III malocclusion results in decreased nasopharyngeal gap with hyoid to shift upward. The influence of class II malocclusion on the upper pharyngeal tract of parents was greater than their children.

Brazilian Thoracic Association Consensus on Sleep-disordered Breathing

Sleep is essential for the proper functioning of all individuals. Sleep-disordered breathing can occur at any age and is a common reason for medical visits. The objective of this consensus is to update knowledge about the main causes of sleep-disordered breathing in adult and pediatric populations, with an emphasis on obstructive sleep apnea. Obstructive sleep apnea is an extremely prevalent but often underdiagnosed disease. It is often accompanied by comorbidities, notably cardiovascular, metabolic, and neurocognitive disorders, which have a significant impact on quality of life and mortality rates. Therefore, to create this consensus, the Sleep-Disordered Breathing Department of the Brazilian Thoracic Association brought together 14 experts with recognized, proven experience in sleep-disordered breathing.