Obstructive sleep apnea and risk of type 2 diabetes mellitus: A systematic review and dose-response meta-analysis of cohort studies

A systematic review of the methodology for examining the relationship between obstructive sleep apnea and type two diabetes mellitus

Background

The association between obstructive sleep apnea (OSA) and type 2 diabetes mellitus (T2DM) has been explored in various studies, revealing inconsistent correlations that impact therapeutic effectiveness. This heterogeneity in findings requires further exploration to understand what may be driving this. Therefore, this study focuses on systematically reviewing the data, classification of variables, and analytical approach to understand if and how this may be contributing to the mixed findings. This review aims to provide insights that can enhance the generalisability of future research findings.

Methods

A comprehensive electronic search was conducted, including EMBASE, MEDLINE, PsycINFO, CINAHL, Web of Science Core Collection, Scopus and specialised sleep journals. The included studies were observational studies published in English from 2011 onwards, involving adults above 18 years with OSA and T2DM or prediabetes, and included a control group. Exclusions were pregnant women, interventional studies, randomised trials, systematic reviews, conference abstracts, case studies and studies without a control group or only with descriptive analysis.

Results

We reviewed 23 studies that met the inclusion criteria. Among cohort studies, 54% did not report attrition rates, and 52% did not detail methods for handling missing data in all studies. Nine studies (39%) predominantly included male participants. Objective measures were prevalent in assessing OSA, with 11 using home portable sleep monitors and four employing clinic polysomnography, though only three validated home sleep monitors. The apnea-hypopnea index was commonly used to define OSA severity, with six studies adapting the American Academy of Sleep Medicine criteria. Two studies utilised validated self-report questionnaires for OSA symptoms. T2DM diagnosis methods varied, with 17 studies using blood samples, two relying only on self-reporting, and four confirmed diagnosis via medical records.

Conclusions

The variability in sample characteristics, data quality, and variable coding may contribute to the mixed finding. This review identifies gaps in using the standardised measures, reporting attrition rates, handling missing data, and including both sexes. Addressing these issues is crucial to enhancing future research generalisability. Standardising diagnostic criteria, considering clinical and sociodemographic factors, and ensuring inclusivity in study populations are essential for advancing understanding and treatment strategies for OSA and T2DM.

Protocol registration

https://www.crd.york.ac.uk/prospero, identifier CRD42023397547.

Sleep Apnea and Atrial Fibrillation: Clinical Features and Screening Diagnostic Options

INTRODUCTION

Obstructive sleep apnea (OSA) is associated with an increased risk of hypertension, coronary artery disease, heart failure (HF), and atrial fibrillation (AF).

MATERIALS AND METHODS

A total of 179 patients aged 34-81 years were included in the study. The median age was 63 years (interquartile range: 56-69 years). Of these patients, 105 (58.7%) were men, and 74 (41.3%) were women; there were cases of paroxysmal (n = 99), persistent (n = 64), and permanent AF (n = 16). All patients underwent investigations including respiratory sleep monitoring, echocardiography, and 24 h Holter electrocardiography monitoring. Statistical analyses were performed using IBM SPSS Statistics 26.0.

RESULTS

OSA was detected in 131 (73.2%) patients. In patients with OSA, paroxysmal AF was commonest (n = 65), followed by persistent AF (n = 51) and permanent AF (n = 15). The patients with sleep apnea had increased body mass index (33.6 kg/m2; p = 0.02), waist circumference (114 cm; p < 0.001), and neck circumference (42 cm; p < 0.001) values. HF (OR 2.9; 95% CI: 1.4-5.9; p = 0.004) and type 2 diabetes (OR 3.6; 95% CI: 1.5-8.3; p = 0.001) were more common in patients with AF and OSA. The STOP-BANG scale (AUC = 0.706 ± 0.044; 95% CI: 0.619-0.792; p < 0.001) and the Berlin questionnaire (AUC = 0.699 ± 0.044; 95% CI: 0.614-0.785) had a higher predictive ability for identifying sleep apnea.

CONCLUSIONS

Patients with AF demonstrate a high prevalence of OSA and an increased association with cardiovascular comorbidities. The STOP-BANG scale and the Berlin questionnaire can be used to screen for OSA in patients with AF.

[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.

Sleep disorders and associated factors among medical students in the Middle East and North Africa: a systematic review and meta-analysis

Sleep disturbances like poor and insufficient sleep are common among medical students in the Middle East and North Africa (MENA) countries; however, the extent of medically defined sleep disorders (SDs) remains unclear. This meta-analysis determines SD prevalence and identifies associated factors among medical students in the MENA. PubMed, Web of Science, Google Scholar, and reference lists of included studies were searched (latest search: June 2022). Meta-analyses included 22 studies and were performed using random-effect models. Included studies used self-reported screening tools for assessing SDs and then estimated the proportion of participants at high risk of developing a SD. Central disorders of hypersomnolence were the most prevalent SD [prevalencepooled range: 30.9% (Jordan) to 62.5% (Saudi Arabia)], followed by insomnia disorders [prevalencepooled range: 30.4% (Jordan) to 59.1% (Morocco)], circadian rhythm sleep-wake disorders [prevalencepooled range: 13.5% (Jordan) to 22.4% (Saudi Arabia)], sleep-related breathing disorders [prevalencepooled range: 12.2% (Jordan) to 22.5% (Pakistan)], sleep-related movement disorders [prevalencepooled range: 5.9% (Egypt) to 30.6% (Saudi Arabia)], and parasomnias [prevalencepooled range: 5.6% (Jordan) to 17.4% (Saudi Arabia)]. Female sex, studying in the latter academic years, having anxiety, excessive internet use, and poor academic performance were significantly associated with SDs. SDs are prevalent among MENA medical students. Implementing student-centered interventions targeting high risk groups in medical schools should be considered to improve students' health and wellbeing.

REM-OSA as a Tool to Understand Both the Architecture of Sleep and Pathogenesis of Sleep Apnea-Literature Review

Sleep is a complex physiological state, which can be divided into the non-rapid eye movement (NREM) phase and the REM phase. Both have some unique features and functions. This difference is best visible in electroencephalography recordings, respiratory system activity, arousals, autonomic nervous system activity, or metabolism. Obstructive sleep apnea (OSA) is a common condition characterized by recurrent episodes of pauses in breathing during sleep caused by blockage of the upper airways. This common condition has multifactorial ethiopathogenesis (e.g., anatomical predisposition, sex, obesity, and age). Within this heterogenous syndrome, some distinctive phenotypes sharing similar clinical features can be recognized, one of them being REM sleep predominant OSA (REM-OSA). The aim of this review was to describe the pathomechanism of REM-OSA phenotype, its specific clinical presentation, and its consequences. Available data suggest that in this group of patients, the severity of specific cardiovascular and metabolic complications is increased. Due to the impact of apneas and hypopneas predominance during REM sleep, patients are more prone to develop hypertension or glucose metabolism impairment. Additionally, due to the specific function of REM sleep, which is predominantly fragmented in the REM-OSA, this group presents with decreased neurocognitive performance, reflected in memory deterioration, and mood changes including depression. REM-OSA clinical diagnosis and treatment can alleviate these outcomes, surpassing the traditional treatment and focusing on a more personalized approach, such as using longer therapy of continuous positive airway pressure or oral appliance use.

Cardiovascular Disease Outcomes Associated with Obstructive Sleep Apnea in Diabetics: A Systematic Review and Meta-Analysis

BACKGROUND

There is significant pathogenic and epidemiological overlap between diabetes and obstructive sleep apnea (OSA). This systematic review aimed to ascertain the association between OSA and cardiovascular disease (CVD) in a diabetic population.

METHODS

The study protocol was registered with PROSPERO (CRD42023404126). On 15 July 2023, a comprehensive search of the literature was performed in PubMed, EBSCO, Scopus, ProQuest, and Web of Science, using keywords and synonyms of OSA, diabetes, and CVD, coupled with specific terms for different CVDs. Only observational studies that reported CVD events in diabetics (with and without OSA) were included. The quality of the studies included in the analysis was assessed using the Newcastle-Ottawa Scale.

RESULTS

In the primary literature search, 8795 studies were identified, of which 9 met the inclusion criteria and included 17,796 participants. Eight studies were eligible for meta-analysis, and a pooled risk ratio (RR) of 1.29 (95% CI = 0.91-1.83) was found for developing CVD in diabetics with OSA at a 95% prediction interval of 0.30-5.60. The included studies showed significant heterogeneity with an I2 value of 91%.

CONCLUSION

These findings show the possible association between OSA and diabetes and their impact on CVDs. Identifying and managing OSA in individuals with diabetes at an early phase could potentially reduce the risk of CVDs and its related complications.

Legal action for access to resources inefficiently made available in health care systems in Brazil: a case study on obstructive sleep apnea

OBJECTIVE

Obstructive sleep apnea (OSA) is a highly prevalent chronic disease, associated with morbidity and mortality. Although effective treatment for OSA is commercially available, their provision is not guaranteed by lines of care throughout Brazil, making legal action necessary. This study aimed at presenting data related to the volume of legal proceedings regarding the access to diagnosis and treatment of OSA in Brazil.

METHODS

This was a descriptive study of national scope, evaluating the period between January of 2016 and December of 2020. The number of lawsuits was analyzed according to the object of the demand (diagnosis or treatment). Projections of total expenses were carried out according to the number of lawsuits.

RESULTS

We identified 1,462 legal proceedings (17.6% and 82.4% related to diagnosis and treatment, respectively). The projection of expenditure for OSA diagnosis in the public and private spheres were R$575,227 and R$188,002, respectively. The projection of expenditure for OSA treatment in the public and private spheres were R$2,656,696 and R$253,050, respectively. There was a reduction in the number of lawsuits between 2017 and 2019.

CONCLUSIONS

Legal action as a strategy for accessing diagnostic and therapeutic resources related to OSA is a recurrent practice, resulting in inefficiency and inequity. The reduction in the number of lawsuits between 2017 and 2019 might be explained by the expansion of local health care policies or by barriers in the journey of patients with OSA, such as difficulties in being referred to specialized health care and low availability of diagnostic resources.

Poorer sleep impairs brain health at midlife

Sleep is an emerging risk factor for dementia but its association with brain health remains unclear. This study included UK Biobank (n = 29,545; mean age = 54.65) participants at imaging visit with sleep measures and brain scans, and a subset (n = 14,206) with cognitive measures. Multiple linear regression analyses were conducted to study the associations between sleep and brain health. Every additional hour of sleep above 7 h/day was associated with 0.10-0.25% lower brain volumes. In contrast, a negative non-linear association was observed between sleep duration, grey matter, and hippocampal volume. Both longer (> 9 h/day) and shorter sleep (< 6 h/day) durations were associated with lower brain volumes and cognitive measures (memory, reaction time, fluid intelligence). Additionally, daytime dozing was associated with lower brain volumes (grey matter and left hippocampus volume) and lower cognitive measures (reaction time and fluid intelligence). Poor sleep (< 6 h/day, > 9 h/day, daytime dozing) at midlife was associated with lower brain health. Sleep may be an important target to improve brain health into old age and delay the onset of dementia.

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.

Mendelian randomization reveals no associations of genetically-predicted obstructive sleep apnea with the risk of type 2 diabetes, nonalcoholic fatty liver disease, and coronary heart disease

BACKGROUND

Obstructive sleep apnea (OSA) has been reported to affect cardiometabolic diseases. However, whether such association is causal is still unknown. Here, we attempt to explore the effect of OSA on type 2 diabetes (T2D), nonalcoholic fatty liver disease (NAFLD) and coronary heart disease (CHD).

METHODS

Genetic variants associated with OSA were requested from a published genome-wide association study (GWAS) and those qualified ones were selected as instrumental variables (IV). Then, the IV-outcome associations were acquired from T2D, NAFLD and CHD GWAS consortia separately. The Mendelian randomization (MR) was designed to estimate the associations of genetically-predicted OSA on T2D, NAFLD and CHD respectively, using the inverse-variance weighted (IVW) method. We applied the Bonferroni method to adjust the p-value. Besides, MR-Egger regression and weighted median methods were adopted as a supplement to IVW. The Cochran's Q value was used to evaluate heterogeneity and the MR-Egger intercept was utilized to assess horizontal pleiotropy, together with MR-PRESSO. The leave-one-out sensitivity analysis was carried out as well.

RESULTS

No MR estimate reached the Bonferroni threshold (p < 0.017). Although the odds ratio of T2D was 3.58 (95% confidence interval (CI) [1.06, 12.11], IVW-p-value = 0.040) using 4 SNPs, such causal association turned insignificant after the removal of SNP rs9937053 located in FTO [OR = 1.30 [0.68, 2.50], IVW p = 0.432]. Besides, we did not find that the predisposition to OSA was associated with CHD [OR = 1.16 [0.70, 1.91], IVW p = 0.560] using 4 SNPs.

CONCLUSION

This MR study reveals that genetic liability to OSA might not be associated with the risk of T2D after the removal of obesity-related instruments. Besides, no causal association was observed between NAFLD and CHD. Further studies should be carried out to verify our findings.

Non-dipping blood pressure pattern is associated with higher risk of new-onset diabetes in hypertensive patients with obstructive sleep apnea: UROSAH data

OBJECTIVE

Impairment of circadian blood pressure (BP) patterns has been associated with cardiovascular risks and events in individuals with hypertension and in general populations, which are more likely to be found in obstructive sleep apnea (OSA). The aim of this study was to investigate the association of non-dipping BP pattern with new-onset diabetes in hypertensive patients with OSA, based on Urumqi Research on Sleep Apnea and Hypertension (UROSAH) data.

MATERIALS AND METHODS

This retrospective cohort study included 1841 hypertensive patients at least 18 years of age, who were diagnosed with OSA without baseline diabetes and had adequate ambulatory blood pressure monitoring (ABPM) data at enrollment. The exposure of interest for the present study was the circadian BP patterns, including non-dipping and dipping BP pattern, and the study outcome was defined as the time from baseline to new-onset diabetes. The associations between circadian BP patterns and new-onset diabetes were assessed using Cox proportional hazard models.

RESULTS

Among 1841 participants (mean age: 48.8 ± 10.5 years, 69.1% male), during the total follow-up of 12172 person-years with a median follow-up of 6.9 (inter quartile range: 6.0-8.0) years, 217 participants developed new-onset diabetes with an incidence rate of 17.8 per 1000 person-years. The proportion of non-dippers and dippers at enrollment in this cohort was 58.8% and 41.2%, respectively. Non-dippers were associated with higher risk of new-onset diabetes compared with dippers (full adjusted hazard ratio [HR]=1.53, 95% confidence interval [CI]: 1.14-2.06, P=0.005). Multiple subgroup and sensitivity analyses yielded similar results. We further explored the association of systolic and diastolic BP patterns with new-onset diabetes separately, and found that diastolic BP non-dippers were associated with higher risk of new-onset diabetes (full adjusted HR=1.54, 95% CI: 1.12-2.10, P=0.008), whereas for systolic BP non-dippers, the association was nonsignificant after adjusted the confounding covariates (full adjusted HR=1.35, 95% CI: 0.98-1.86, P=0.070).

CONCLUSIONS

Non-dipping BP pattern is associated with an approximately 1.5-fold higher risk of new-onset diabetes in hypertensive patients with OSA, suggesting that non-dipping BP pattern may be an important clinical implication for the early prevention of diabetes in hypertensive patients with OSA.

Obstructive sleep apnea, prediabetes and progression of type 2 diabetes: A systematic review and meta-analysis

AIMS/INTRODUCTION

Obstructive sleep apnea (OSA) is related to prediabetes and diabetes. Whether patients with OSA have a higher risk of prediabetes/diabetes remains unclear. We aimed to carry out a meta-analysis of published studies to evaluate the relationships between OSA and prediabetes and diabetes, and the impact of the severity of OSA on diabetes.

MATERIALS AND METHODS

The PubMed, EMBASE and Cochrane databases were searched from January 2011 to July 2021. The associations between OSA and impaired fasting glucose, impaired glucose tolerance, impaired glucose regulation and diabetes mellitus were analyzed. We estimated the pooled odds ratios using fixed or random effects models. We included 25 studies comprising a total of 154,948 patients with OSA and risk factors for prediabetes/diabetes (20 and 16, respectively) in the analysis.

RESULTS

OSA was associated with a higher risk of impaired fasting glucose, impaired glucose tolerance, impaired glucose regulation and diabetes mellitus in the cohort studies and cross-sectional studies. The pooled odds ratios were 2.34 (95% confidence interval [CI] 1.16-4.72), 1.58 (95% CI 1.15-2.15), 1.65 (95% CI 1.12-2.42), 2.15 (95% CI 1.68-2.75) and 3.62 (95% CI 2.75-4.75), respectively. Subgroup analyses were based on the proportions of men and women. The results showed that OSA was a risk factor, and there was no significant difference between the two groups. The risk of diabetes increased with the severity of OSA.

CONCLUSIONS

The risk of developing prediabetes and diabetes was higher in patients with OSA.

Comparison of polysomnographic and cephalometric parameters based on positional and rapid eye movement sleep dependency in obstructive sleep apnea

The aim of this study is to investigate the differences in polysomnographic and cephalometric features according to positional and rapid eye movement (REM) sleep dependencies in obstructive sleep apnea patients. Standard polysomnography and cephalometric analyses were performed on 133 OSA patients. The subjects were categorized into positional and non-positional, and REM-related and not-REM-related OSA groups according to positional and REM sleep dependency on severity of sleep apnea. Polysomnographic and cephalometric parameters were compared between groups. Positional and REM-related OSA patients showed significantly lower non-supine apnea-hypopnea index (AHI), non-REM (NREM) AHI and overall AHI and higher NREM oxygen saturation (SpO₂) and mean SpO₂ compared to non-positional and not-REM-related OSA patients, respectively. Cephalometric features between positional and non-positional OSA patients did not show any significant differences. However, REM-related OSA patients showed significantly larger inferior oral airway space and shorter perpendicular distance between mandibular plane and anterior hyoid bone and the distance between uvula and posterior nasal spine, and narrower maximum width of soft palate than not-REM-related OSA patients. Positional and REM-related OSA patients have lower severity of sleep apnea, suggesting the possibility of lower collapsibility of the upper airway. REM sleep dependency was associated with anatomical factors, while positional dependency did not show such a tendency.

Economic evaluation of CPAP therapy for obstructive sleep apnea: a scoping review and evidence map

PURPOSE

To synthesize findings of economic evaluations investigating cost-effectiveness of continuous positive airway pressure (CPAP) for obstructive sleep apnea (OSA) and of strategies of organization of care related to CPAP therapy.

METHODS

Scoping review with searches conducted in MEDLINE, CRD, LILACS, and Embase in August 2020. Eligible studies were economic evaluations comparing CPAP to other alternative or assessing strategies of care for CPAP therapy. Results were presented narratively, and incremental cost-effectiveness ratios (ICER) were presented in evidence maps.

RESULTS

Of 34 studies, 3 concluded that CPAP is less costly and more effective when compared to usual care. Most studies indicated that CPAP is associated with better health outcomes, but at higher prices. ICER ranged from USD 316 to 98,793 per quality-adjusted life years (QALY) gained (median 16,499; IQR 8267 to 33,119). One study concluded that CPAP is more costly and less effective, when treatment is applied to all patients, regardless of disease severity. Variability of ICER was mainly due to definition of population and applied time horizons. When CPAP was compared to mandibular advancement device, ICER ranged from USD 21,153 to 361,028 (median 89,671; IQR 26,829 to 295,983), which represents the investment in CPAP therapy required to obtain one extra QALY. Three studies assessed the effects of organizing CPAP therapy in primary care, which was cost-effective or cost-saving.

CONCLUSIONS

Compared to usual care, CPAP is cost-effective after the second year of treatment, when indicated for moderate-to-severe OSA. CPAP therapy may be even more cost-effective by using different strategies of organization of care. These findings may inform decision making related to CPAP reimbursement in health systems.

CLINICAL TRIAL REGISTRATION NUMBER

Not applicable.

Obesity and Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is characterized by upper airway collapse during sleep. Chronic intermittent hypoxia, sleep fragmentation, and inflammatory activation are the main pathophysiological mechanisms of OSA. OSA is highly prevalent in obese patients and may contribute to cardiometabolic risk by exerting detrimental effects on adipose tissue metabolism and potentiating the adipose tissue dysfunction typically found in obesity. This chapter will provide an update on: (a) the epidemiological studies linking obesity and OSA; (b) the studies exploring the effects of intermittent hypoxia and sleep fragmentation on the adipose tissue; (c) the effects of OSA treatment with continuous positive airway pressure (CPAP) on metabolic derangements; and (d) current research on new anti-diabetic drugs that could be useful in the treatment of obese OSA patients.

Association Between Abdominal Adipose Tissue Distribution and Obstructive Sleep Apnea in Chinese Obese Patients

PURPOSE

Factors related to the occurrence of obstructive sleep apnea syndrome (OSAS) in obesity have not been fully clarified. The aim of this study was to identify the association between OSAS and abdominal fat distribution in a cohort of Chinese obese patients.

METHODS

This cross-sectional study collected demographic data of 122 obese patients who were admitted into the in-patient unit of the Department of Endocrinology, Shanghai Tenth People's Hospital from July 2018 to January 2021. OSAS was diagnosed based on the results of overnight polysomnography, and the abdominal fat distribution was measured by bioelectrical impedance analysis (BIA). Univariate and multivariate logistic regression analyses were used to investigate the association between OSAS and the distribution of abdominal fat.

RESULTS

(1) The mean age (SD) of the obese patients included was 32.44 (11.81) years old, and the overall incidence rate of OSAS was 51.06%. Twenty-four (25.53%) patients had mild OSAS, 10 (10.64%) had moderate OSAS, and 14 (14.89%) had severe OSAS. The apnea hypopnea index (AHI) of men was significantly higher than that of women (5.50, interquartile range (IQR) 3.80-30.6 vs. 4.2, IQR 1.4-12 events/h, p = 0.014). Meanwhile, men had a significantly higher visceral fat area when compared with women (180.29 ± 51.64 vs. 143.88 ± 53.42 cm², p = 0.002). (2) Patients with OSAS had a significantly higher waist circumference, fasting plasma glucose, 2 h postprandial plasma glucose, glycated hemoglobin, and visceral fat area than patients without OSAS (all p < 0.05). (3) AHI was significantly positively associated with BMI, neck circumference, waist circumference, and visceral fat area (r = 0.306, p = 0.003; r = 0.380, p < 0.001; r = 0.328, p = 0.002; r = 0.420, p < 0.001) but not with subcutaneous fat area (p = 0.094). Multivariate analysis demonstrated that abdominal fat area and fasting plasma glucose were independent risk factors for OSAS (odds ratio, 1.016; 95% confidence interval, 1.005-1,026, p = 0.005; odds ratio, 1.618; 95% confidence interval, 1.149-2.278, p = 0.006).

CONCLUSIONS

In obese patients, the abdominal visceral adipose deposit but not the subcutaneous fat area was associated with OSAS and was an independent risk factor for OSAS. Therefore, improving the distribution of abdominal fat may contribute to alleviating the severity of OSAS in obesity.

Diabetes and prediabetes in patients with heart failure and preserved ejection fraction

Aim

There is an association between heart failure with preserved ejection fraction (HFpEF) and insulin resistance, but less is known about the diabetic continuum, and in particular about pre‐diabetes, in HFpEF. We examined characteristics and outcomes of participants with diabetes or pre‐diabetes in PARAGON‐HF.

Methods and results

Patients aged ≥50 years with left ventricular ejection fraction ≥45%, structural heart disease and elevated N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) were eligible. Patients were classified according to glycated haemoglobin (HbA1c): (i) normal HbA1c, <6.0%; (ii) pre‐diabetes, 6.0%–6.4%; (iii) diabetes, ≥6.5% or history of diabetes. The primary outcome was a composite of cardiovascular (CV) death and total heart failure hospitalizations (HFH). Of 4796 patients, 50% had diabetes and 18% had pre‐diabetes. Compared to patients with normal HbA1c, patients with pre‐diabetes and diabetes more often were obese, had a history of myocardial infarction and had lower Kansas City Cardiomyopathy Questionnaire scores, while patients with diabetes had more clinical evidence of congestion, but similar NT‐proBNP concentrations. The risks of the primary composite outcome (rate ratio [RR] 1.59, 95% confidence interval [CI] 1.35–1.88), total HFH (RR 1.67, 95% CI 1.39–2.02) and CV death (hazard ratio [HR] 1.35, 95% CI 1.07–1.71) were higher among patients with diabetes, compared to those with normal HbA1c. Patients with pre‐diabetes had a higher risk (which was intermediate between that of patients with diabetes and those with normal HbA1c) of the primary outcome (HR 1.27, 95% CI 1.00–1.60) and HFH (HR 1.35, 95% CI 1.03–1.77), but not of CV death (HR 1.02, 95% CI 0.75–1.40). Patients with diabetes treated with insulin had worse outcomes than those not, and those with ‘lean diabetes’ had similar mortality rates to those with a higher body mass index, but lower rates of HFH.

Conclusion

Pre‐diabetes is common in patients with HFpEF and is associated with worse clinical status and greater risk of HFH. Clinical Trial Registration: ClinicalTrials.gov Identifier NCT01920711.

The Relationship Between Primary Sleep Disorders and Temporomandibular Disorders: An 8-Year Nationwide Cohort Study in South Korea

Background

While evidence is accumulating to propose a specific contribution of sleep disorders and low quality sleep in the pathogenesis of temporomandibular disorders (TMD), management of primary sleep disorders in the process of preventing and treating TMD still remains scientifically unsupported.

Objective

To investigate the association of primary sleep disorders with TMD risk in South Korea.

Patients and Methods

This study was based on the National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) of South Korea with 468,882 participants. After excluding participants diagnosed in 2002, those with a diagnosis of a primary sleep disorder in 2003–2005 were recruited. All participants diagnosed with TMD between January 1, 2006 and December 31, 2013 received follow-up. Cox proportional hazards regression was performed to determine the adjusted hazard ratios (aHR) and 95% confidence interval (CI) for TMD according to the presence or absence of a primary sleep disorder diagnosis.

Results

After adjusting for all covariates, primary sleep disorder patients had a 44% higher risk for TMD compared with non-sleep disorder participants (aHR 1.44, 95% CI 1.02–2.04). The incidence rate of TMD was nearly twice as high in participants with sleep disorders compared with those without (6.08 vs 3.27, per 10⁴ person-years). In subgroup analysis, an association was observed with those over 60 years old or who frequently exercised physically.

Conclusion

Primary sleep disorders could be an important independent risk factor for the initiation and maintenance of TMD. Patients with sleep disorders should be monitored for possible co-occurrence of TMD-related symptoms that could aggravate sleep disorders in turn.

Hemoglobin A1c in combination with fasting plasma glucose trumps fasting plasma glucose alone as predictive indicators for diabetes mellitus: an ambidirectional cohort study of Thai people with impaired fasting glucose

INTRODUCTION

This ambidirectional cohort study aimed to assess the performance of combining hemoglobin A1c (HbA1c) to fasting plasma glucose (FPG) for estimation of progression rate to diabetes mellitus (DM) and to explore the risk factors of DM in patients with impaired fasting glucose (IFG).

RESEARCH DESIGN AND METHODS

Patients with IFG were eligible for this study. IFG was defined as FPG of 100-125 mg/dL. Progression rates to DM were estimated using Kaplan-Meier analysis. Risk factors of DM were explored by Cox regression analysis.

RESULTS

3011 patients were enrolled with median follow-up time of 8 years (range: 6 months-29 years). Progression rates to DM in patients with FPG 100-109 mg/dL and 110-125 mg/dL were 2.64 and 4.79 per 100 person-years. After adjusting covariables, compared with patients with FPG 100-109 mg/dL plus normal HbA1c (<5.7%), hazard ratios (95% CI) of patients with FPG 110-125 plus normal HbA1c, FBG 100-109 plus abnormal HbA1c (5.7%-6.49%), and FPG 110-125 plus abnormal HbA1c were 5.89 (2.37 to 14.63), 16.30 (8.59 to 30.92), and 33.84 (16.41 to 69.78), respectively. Body mass index ≥27.5 kg/m², serum triglyceride level ≥150 mg/dL, family history of DM, and low level of high-density lipoprotein-cholesterol were independently associated with risk of DM in patients with IFG.

CONCLUSIONS

Patients with both IFG and abnormal HbA1c had higher risk of DM than patients with IFG alone. Therefore, performing HbA1c in combination with FPG helps to identify subgroups of people with IFG at highest risk of DM. These patients should have the highest priority in diabetes prevention programs, especially in countries with low and limited resources.

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

Materials and Methods

We screened four databases (PubMed, Embase, Cochran Library, and CNKI) for the observational studies about the OSA and T2DM. Studies were collected from database establishment to October 2020. We performed a traditional subgroup meta-analysis. What is more, linear and spline dose-response models were applied to assess the association between apnea-hypopnea index (AHI), an indicator to evaluate the severity of OSA, and the risk of T2DM. Review Manager, version 5.3, software and Stata 16.0 were used for the analysis.

Result

Seven observational studies were included in the research. We excluded a study in the conventional meta-analysis. In the subgroup analysis, mild-dose AHI increased the risk of T2DM (odds ratio = 1.23, 95% confidence interval = 1.06–1.41, P < 0.05). Moderate-dose AHI increased the risk of T2DM with a higher odds ratio (OR = 1.35, 95% CI = 1.13–1.61, P < 0.05). Moderate-to-severe-dose AHI increased the risk of T2DM with a higher odds ratio (OR = 2.14, 95% CI = 1.72–2.67, P < 0.05). Severe-dose AHI increased the risk of T2DM with a higher odds ratio (OR = 2.19 95% CI = 1.30–3.68, P < 0.05). Furthermore, the spline and linear dose-response meta-analysis results revealed that the risk of T2DM increased with increasing AHI values.

Conclusion

Through the dose-response meta-analysis, we found a potential dose-response relationship existed between the severity of OSA and the risk of T2DM. This relationship in our passage should be considered in the prevention of T2DM in the future.

The role of acetazolamide in sleep apnea at sea level: a systematic review and meta-analysis

STUDY OBJECTIVES

The recognition of specific endotypes as drivers of sleep apnea suggests the need of therapies targeting individual mechanisms. Acetazolamide is known to stabilize respiration at high altitude but benefits at sea level are less well understood.

METHODS

All controlled studies of acetazolamide in obstructive sleep apnea and/or central sleep apnea (CSA) were evaluated. The primary outcome was the apnea-hypopnea index.

RESULTS

Fifteen trials with a total of 256 patients were pooled in our systematic review. Acetazolamide reduced the overall apnea-hypopnea index (mean difference [MD] -15.82, 95% CI: -21.91 to -9.74, P < .00001) in central sleep apnea (MD -22.60, 95% CI: -29.11 to -16.09, P < .00001), but not in obstructive sleep apnea (MD -10.29, 95% CI: -33.34 to 12.77, P = .38). Acetazolamide reduced the respiratory related arousal index (MD -0.82, 95% CI: -1.56 to -0.08, P = .03), improved partial arterial of oxygen (MD 11.62, 95% CI: 9.13-14.11, P < .00001), mean oxygen saturation (MD 1.78, 95% CI: 0.53-3.04, P = .005), total sleep time (MD 25.74, 95% CI: 4.10-47.38, P = .02), N2 sleep (MD 3.34, 95% CI: 0.12-6.56, P = .04) and sleep efficiency (MD 4.83, 95% CI: 0.53-9.13, P = .03).

CONCLUSIONS

Acetazolamide improves the apnea-hypopnea index and several sleep metrics in central sleep apnea. The drug may be of clinical benefit in patients with high loop gain apnea of various etiologies and patterns. The existence of high heterogeneity is an important limitation in applicability of our analysis.

SYSTEMATIC REVIEW REGISTRATION

Registry: PROSPERO; Name: The effect of acetazolamide in patients with sleep apnea at sea level: a systematic review and meta analysis; URL: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020163316; Identifier: CRD42020163316.

Association between comorbid sleep apnoea-hypopnoea syndrome and prognosis of intensive care patients: a retrospective cohort study

OBJECTIVE

In this study, we investigated the association between comorbid sleep apnoea-hypopnoea syndrome (SAHS) and the prognosis of patients in an intensive care unit (ICU) to determine whether this relationship varies between different disease subgroups.

METHODS

We conducted a retrospective cohort study using publicly available information from the critical care database Medical Information Mart for Intensive Care III. Adults (≥18 years of age) who attended the ICU for the first time were enrolled. Demographic information and clinical data were obtained from each patient. The primary outcome was 30-day mortality after ICU admission, and the secondary outcomes were in-hospital and ICU mortality. Multivariate logistic regression and Cox regression analyses were used to examine the associations between SAHS comorbidities and the research outcomes. Propensity score matching was used to adjust for potential confounding variables.

RESULTS

Of the 32 989 patients enrolled, 1918 (5.81%) were diagnosed with SAHS as a comorbid condition. Patients with SAHS had a significantly lower 30-day mortality rate compared with those without SAHS (5.27% vs 13.65%, respectively; p<0.001). The frequency of chronic obstructive pulmonary disease, cerebral disease, cardiovascular disease, hypertension, diabetes mellitus and renal failure was significantly different between the two groups. Patients with SAHS demonstrated significantly longer survival compared with patients without SAHS. Multivariate Cox proportional hazards regression identified a significant relationship between SAHS and mortality within 30 days (adjusted HR=0.610, 95% CI 0.499 to 0.747, p<0.0001).

CONCLUSION

SAHS as a comorbid condition decreases the risk of 30-day mortality, in-hospital mortality and ICU mortality among ICU patients.

An umbrella review of systematic reviews and meta-analyses of observational investigations of obstructive sleep apnea and health outcomes

Purpose

The previous analysis of systematic reviews and meta-analyses have illustrated that obstructive sleep apnea (OSA) is correlated with multiple health outcomes. In the present research, our main aim was to execute an umbrella review to assess the available evidence for the associations between OSA and health outcomes.

Methods

Herein, a meta-analysis of previous observational investigations that have reported associations between OSA and health outcomes in all human populations and settings was performed. We used these studies to execute an umbrella review of available meta-analyses and systematic reviews.

Results

Sixty-six articles comprising 136 unique outcomes were enrolled in this analysis. Of the 136 unique outcomes, 111 unique outcomes had significant associations (p < 0.05). Only 7 outcomes (coronary revascularization after PCI, postoperative respiratory failure, steatosis, alaninetrans aminase (ALT) elevation, metabolic syndrome (MS), psoriasis, and Parkinson’s disease) had a high quality of evidence. Twenty-four outcomes had a moderate quality of evidence, and the remaining 80 outcomes had a weak quality of evidence. Sixty-nine outcomes exhibited significant heterogeneity. Twenty-five outcomes exhibited publication bias. Sixty-three (95%) studies showed critically low methodological quality.

Conclusion

Among the 66 meta-analyses exploring 136 unique outcomes, only 7 statistically significant outcomes were rated as high quality of evidence. OSA may correlate with an increased risk of coronary revascularization after PCI, postoperative respiratory failure, steatosis, ALT elevation, MS, psoriasis, and Parkinson’s disease.

Prevalence, Risk Factors, and Comorbidities of Obstructive Sleep Apnea Risk Among a Working Population in Kuwait: A Cross-Sectional Study

Background: Obstructive sleep apnea (OSA) affects a considerable proportion of adults globally and is associated with elevated morbidity and mortality. Given the lack of epidemiologic data on the burden of OSA in Kuwait, this study sought to estimate its prevalence, associated risk factors, and comorbid conditions among a working population in Kuwait. Methods: This was a cross-sectional study of a sample of working adults (n = 651) from public institutions in Kuwait. High/low risk for OSA was ascertained according to the Berlin Questionnaire criteria. Participants self-reported their coexisting health conditions. Associations were assessed using Poisson regression with robust variance estimation; adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) were estimated. Results: Overall, 20.0% (130/651) of participants were classified as being at high risk for OSA, with more male than female subjects being at high risk (24.0% [56/233] vs. 17.7% [74/418], P = 0.053), though this difference did not gain statistical significance. Moreover, a high risk for OSA was more common among older and obese subjects. Factors associated with increased prevalence of a high risk for OSA included current smoking status (aPR = 1.58, 95% CI: 1.02-2.06), longer hours spent watching television (1.76, 1.10-2.81), and lower self-perceived physical health (2.11, 1.15-3.87). However, decreasing trends in the prevalence of high risk for OSA were observed with frequent engagement in vigorous physical activity and longer nightly sleep duration. Compared to those at a low risk for OSA, the subjects at high risk for OSA were more likely to have insomnia disorder (2.83, 1.81-4.41), diabetes (1.94, 1.15-3.27), hypertension (3.00, 1.75-5.16), and depression (4.47, 1.80-11.08). Conclusion: This study estimated that 1/5 of working adults in Kuwait were at high risk for OSA, and the prevalence varied according to personal characteristics and lifestyle factors. Also, a high risk for OSA classification was associated with multiple comorbid health conditions.

Sleep Duration and Snoring at Midlife in Relation to Healthy Aging in Women 70 Years of Age or Older

PURPOSE

Both short and long sleep durations are associated with higher mortality. This study examined the association between sleep duration and overall health among those who survive to older ages.

PARTICIPANTS AND METHODS

In the Nurses' Health Study, participants without major chronic diseases in 1986 and survived to age 70 years or older in 1995-2001 were included. Habitual sleep duration and snoring were self-reported in 1986. Healthy aging was defined as being free of 11 major chronic diseases and having no cognitive impairment, physical impairment, or mental health limitations. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for healthy aging.

RESULTS

Of the 12,304 participants, 1354 (11.0%) achieved healthy aging. We observed a non-linear association between sleep duration and the odds of achieving healthy aging. Compared with women sleeping 7 hours per day, women with longer sleep duration were less likely to achieve healthy aging; there was also a suggestion of lower odds of healthy aging for shorter sleepers, although the associations did not reach statistical significance: the multivariate-adjusted ORs (95% CIs) of healthy aging for those sleeping ≤5, 6, 8, and ≥9 hours were 0.94 (0.70, 1.27), 0.88 (0.76, 1.02), 0.83 (0.72, 0.96), and 0.60 (0.43, 0.84), respectively. Similar non-linear associations were consistently observed for individual dimensions of healthy aging. Regular snoring was associated with 31% lower odds of healthy aging (95% CI: 0.54, 0.88), which was primarily due to lower odds of having no major chronic diseases.

CONCLUSION

Both short and long sleep durations as well as regular snoring at midlife were associated with lower odds of healthy aging in later life.

Systematic review of clinical practice guidelines to identify recommendations for sleep in type 2 diabetes mellitus management

INTRODUCTION

Sleep quality, quantity and timing have been shown to impact glycaemic control, with a role in insulin sensitivity, glucose tolerance and HbA1C levels, in both diabetic and non-diabetic populations. The aim of this study was to identify recommendations for sleep assessment and management in international clinical practice guidelines focused on type 2 diabetes mellitus management in adults.

STUDY DESIGN

Systematic Review.

METHODOLOGY

Clinical practice guidelines which focused on the management of type 2 diabetes mellitus in adults were included (n = 35). Two independent reviewers utilised the Appraisal of Guidelines for Research and Evaluation tool (AGREE) II and a third reviewer resolved any disagreements. Included guidelines were assessed for recommendations about sleep in diabetes management (n = 14). Data were extracted on sleep recommendations ,themes were generated from the extracted data and narrative syntheses were created.

RESULTS

From 1114 identified papers, 35 guidelines met the inclusion criteria. Fourteen of these guidelines included recommendations pertaining to sleep, which broadly fell into five categories; sleep assessment, sleep as a therapeutic target, sleep and co-morbidities of type 2 diabetes mellitus, shift work and sleep and driving. Recommendations varied across guidelines.

CONCLUSION

Few guidelines provided recommendations relating to assessment and management of sleep in type 2 diabetes care. Most of the recommendations were related to obstructive sleep apnoea. However, few guidelines discussed sleep as a therapeutic intervention for diabetes mellitus or described the potential importance of sleep quality and duration in glycaemic control. Prospero registration number: CRD42020142136.

The Association Between Obstructive Sleep Apnea Defined by 3 Percent Oxygen Desaturation or Arousal Definition and Self-Reported Cardiovascular Disease in the Sleep Heart Health Study

Background

Studies have established that OSA defined using a hypopnea definition requiring a ≥4% oxygen desaturation (AHI4%) is associated with cardiovascular (CVD) or coronary heart (CHD) disease. This study determined whether OSA defined using a hypopnea definition characterized by a ≥3% oxygen desaturation or an arousal (AHI3%A) is associated with CVD/CHD.

Methods

Data were analyzed from 6307 Sleep Heart Health Study participants who had polysomnography. Self-reported CVD included angina, heart attack, heart failure, stroke, previous coronary bypass surgery or angioplasty. Self-reported CHD included the aforementioned conditions but not stroke or heart failure. The association between OSA and CVD/CHD was examined using logistic regression models with stepwise inclusion of demographic, anthropometric, social/behavioral and co-morbid medical conditions. A parsimonious model in which diabetes and hypertension were excluded because of their potential to be on the causal pathway between OSA and CVD/CHD also was constructed.

Results

For CVD, the odds ratios and 95% confidence intervals for AHI3%A ≥30/hour were 1.39 (1.03-1.87) and 1.45 (1.09-1.94) in the fully adjusted and parsimonious models. Results for CHD were 1.29 (0.96-1.74) and 1.36 (0.99-1.85). In participants without OSA according to more stringent AHI4% criteria but with OSA using the AHI3%A definition, similar findings were observed.

Conclusion

OSA defined using an AHI3%A is associated with both CVD and CHD. Use of a more restrictive AHI4% definition will misidentify a large number of individuals with OSA who have CVD or CHD. These individuals may be denied access to therapy, potentially worsening their underlying CVD or CHD.