The Association between Obstructive Sleep Apnea on Diabetic Kidney Disease: A Systematic Review and Meta-Analysis

Obstructive sleep apnea: Overlooked comorbidity in patients with diabetes

In this review article, we explore the interplay between obstructive sleep apnea (OSA) and type 2 diabetes mellitus (T2DM), highlighting a significant yet often overlooked comorbidity. We delve into the pathophysiological links between OSA and diabetes, specifically how OSA exacerbates insulin resistance and disrupts glucose metabolism. The research examines the prevalence of OSA in diabetic patients and its role in worsening diabetes-related complications. Emphasizing the importance of comprehensive management, including weight control and positive airway pressure therapy, the study advocates integrated approaches to improve outcomes for patients with T2DM and OSA. This review underscores the necessity of recognizing and addressing OSA in diabetes care to ensure more effective treatment and better patient outcomes.

Nocturnal hypoxemic burden and micro- and macrovascular disease in patients with type 2 diabetes

BACKGROUND

Micro- and macrovascular diseases are common in patients with type 2 diabetes mellitus (T2D) and may be partly caused by nocturnal hypoxemia. The study aimed to characterize the composition of nocturnal hypoxemic burden and to assess its association with micro- and macrovascular disease in patients with T2D.

METHODS

This cross-sectional analysis includes overnight oximetry from 1247 patients with T2D enrolled in the DIACORE (DIAbetes COhoRtE) study. Night-time spent below a peripheral oxygen saturation of 90% (T90) as well as T90 associated with non-specific drifts in oxygen saturation (T90non - specific), T90 associated with acute oxygen desaturation (T90desaturation) and desaturation depths were assessed. Binary logistic regression analyses adjusted for known risk factors (age, sex, smoking status, waist-hip ratio, duration of T2D, HbA1c, pulse pressure, low-density lipoprotein, use of statins, and use of renin-angiotensin-aldosterone system inhibitors) were used to assess the associations of such parameters of hypoxemic burden with chronic kidney disease (CKD) as a manifestation of microvascular disease and a composite of cardiovascular diseases (CVD) reflecting macrovascular disease.

RESULTS

Patients with long T90 were significantly more often affected by CKD and CVD than patients with a lower hypoxemic burden (CKD 38% vs. 28%, p < 0.001; CVD 30% vs. 21%, p < 0.001). Continuous T90desaturation and desaturation depth were associated with CKD (adjusted OR 1.01 per unit, 95% CI [1.00; 1.01], p = 0.008 and OR 1.30, 95% CI [1.06; 1.61], p = 0.013, respectively) independently of other known risk factors for CKD. For CVD there was a thresholdeffect, and only severly and very severly increased T90non-specific was associated with CVD ([Q3;Q4] versus [Q1;Q2], adjusted OR 1.51, 95% CI [1.12; 2.05], p = 0.008) independently of other known risk factors for CVD.

CONCLUSION

While hypoxemic burden due to oxygen desaturations and the magnitude of desaturation depth were significantly associated with CKD, only severe hypoxemic burden due to non-specific drifts was associated with CVD. Specific types of hypoxemic burden may be related to micro- and macrovascular disease.

Hypoxia-Induced Insulin Resistance Mediates the Elevated Cardiovascular Risk in Patients with Obstructive Sleep Apnea: A Comprehensive Review

Patients with obstructive sleep apnea (OSA) experience insulin resistance and its clinical consequences, including hypertriglyceridemia, reduced high density lipoprotein-associated cholesterol (HDL-c), visceral adiposity, hepatic steatosis, increased epicardial fat thickness, essential hypertension, glucose intolerance, increased risk for type 2 diabetes, chronic kidney disease, subclinical vascular damage, and increased risk for cardiovascular events. Obesity is a major contributor to OSA. The prevalence of OSA is almost universal among patients with severe obesity undergoing bariatric surgery. However, insulin resistance and its clinical complications occur in OSA patients irrespective of general obesity (body mass index). In OSA patients, apnea episodes during sleep induce oxyhemoglobin desaturation and tissue hypoxia. Insulin resistance is an adaptive response to tissue hypoxia and develops in conditions with limited tissue oxygen supply, including healthy subjects exposed to hypobaric hypoxia (high altitude) and OSA patients. Indicators of oxyhemoglobin desaturation have been robustly and independently linked to insulin resistance and its clinical manifestations in patients with OSA. Insulin resistance mediates the elevated rate of type 2 diabetes, chronic kidney disease, and cardiovascular disease unexplained with traditional cardiovascular risk factors present in OSA patients. Pathophysiological processes underlying hypoxia-induced insulin resistance involve hypoxia inducible factor-1 upregulation and peroxisome proliferator-activated receptor-gamma (PPAR- γ ) downregulation. In human adipose tissue, PPAR- γ activity promotes glucose transport into adipocytes, lipid droplet biogenesis, and whole-body insulin sensitivity. Silencing of PPAR- γ in the adipose tissue reduces glucose uptake and fat accumulation into adipocytes and promotes insulin resistance. In conclusion, tissue hypoxia drives insulin resistance and its clinical consequences in patients with OSA, regardless of body mass index.

Evaluation of bi-directional causal association between obstructive sleep apnoea syndrome and diabetic microangiopathy: a Mendelian randomization study

Background

The relationship between obstructive sleep apnea syndrome (OSAS) and diabetic microangiopathy remains controversial.

Objective

This study aimed to use bidirectional two-sample Mendelian Randomization (MR) to assess the causal relationship between OSAS and diabetic microangiopathy.

Methods

First, we used the Linkage Disequilibrium Score Regression(LDSC) analysis to assess the genetic correlation. Then, the bidirectional two-sample MR study was conducted in two stages: OSAS and lung function-related indicators (forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)) were investigated as exposures, with diabetic microangiopathy as the outcome in the first stage, and genetic tools were used as proxy variables for OSAS and lung function-related measures in the second step. Genome-wide association study data came from the open GWAS database. We used Inverse-Variance Weighted (IVW), MR-Egger regression, Weighted median, Simple mode, and Weighted mode for effect estimation and pleiotropy testing. We also performed sensitivity analyses to test the robustness of the results. Furthermore, we performed multivariate and mediation MR analyses.

Results

In the LDSC analysis, We found a genetic correlation between OSAS, FVC, FEV 1, and diabetic microangiopathy. In the MR analysis, based on IVW analysis, genetically predicted OSAS was positively correlated with the incidence of diabetic retinopathy (DR), diabetic kidney disease (DKD), and diabetic neuropathy (DN). In the subgroup analysis of DR, there was a significant causal relationship between OSAS and background diabetic retinopathy (BDR) and proliferative diabetic retinopathy (PDR). The reverse MR did not show a correlation between the incidence of diabetic microangiopathy and OSAS. Reduced FVC had a potential causal relationship with increased incidence of DR and PDR. Reduced FEV1 had a potential causal relationship with the increased incidence of BDR, PDR, and DKD. Multivariate MR analysis showed that the association between OSAS and diabetic microangiopathy remained significant after adjusting for confounding factors. However, we did not find the significant mediating factors.

Conclusion

Our results suggest that OSAS may be a cause of the development of diabetic microangiopathy, and OSAS may also be associated with a high risk of diabetic microangiopathy, providing a reference for a better understanding of the prevention of diabetic microangiopathy.

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.

Obstructive sleep apnea: Beyond the dogma of obesity!

Obstructive sleep apnea (OSA) has long been studied in patients with obesity and type 2 diabetes mellitus (T2DM), due to the fact that both disorders are commonly associated with an increased body mass index (BMI). However, a link between OSA and non-obese diabetic patients is still not very elaborated, nor heavily explored. In this review, we elucidate some proposed mechanisms for the link between OSA and diabetic patients both with and beyond obesity, shedding the light on the latter case. One such mechanism is oxidative stress, a phenomenon of reactive oxygen species (ROS) imbalance seen in both of the previously mentioned disorders. A plausible explanation for the OSA-induced ROS production is the repeating episodes of hypoxia and reperfusion and their effect on the mitochondrial electron transport chain. This paper explores the literature regarding ROS imbalance as the possible missing link between OSA and Diabetes Mellitus beyond obesity, while still mentioning other possible proposed mechanisms such as a dysregulated autonomic nervous system (ANS), as well as mechanical and craniofacial abnormalities. This paper also suggests a link between OSA and diabetic complications, while exploring the clinical progress made in treating the former disorder with anti-oxidant and hypo-glycemic drugs. If further investigated, these findings could help identify novel therapeutic interventions for the treatment of OSA and Diabetic patients.

Respiratory effort during sleep and the rate of prevalent type 2 diabetes in obstructive sleep apnoea

AIM

To determine the association between total sleep time (TST) spent in increased respiratory effort (RE) and the prevalence of type 2 diabetes in a large cohort of individuals with suspected obstructive sleep apnoea (OSA) referred for in-laboratory polysomnography (PSG).

MATERIALS AND METHODS

We conducted a retrospective cross-sectional study using the clinical data of 1128 patients. Non-invasive measurements of RE were derived from the sleep mandibular jaw movements (MJM) bio-signal. An explainable machine-learning model was built to predict prevalent type 2 diabetes from clinical data, standard PSG indices, and MJM-derived parameters (including the proportion of TST spent with increased respiratory effort [REMOV [%TST]).

RESULTS

Original data were randomly assigned to training (n = 853) and validation (n = 275) subsets. The classification model based on 18 input features including REMOV showed good performance for predicting prevalent type 2 diabetes (sensitivity = 0.81, specificity = 0.89). Post hoc interpretation using the Shapley additive explanation method found that a high value of REMOV was the most important risk factor associated with type 2 diabetes after traditional clinical variables (age, sex, body mass index), and ahead of standard PSG metrics including the apnoea-hypopnea and oxygen desaturation indices.

CONCLUSIONS

These findings show for the first time that the proportion of sleep time spent in increased RE (assessed through MJM measurements) is an important predictor of the association with type 2 diabetes in individuals with OSA.

Continuous Positive Airway Pressure Effect on Albuminuria Progression in Patients with Obstructive Sleep Apnea and Diabetic Kidney Disease: A Randomized Clinical Trial

Rationale: Obstructive sleep apnea (OSA) is associated with impaired glycemic control and a higher risk of vascular complications, such as diabetic kidney disease (DKD). However, the effect of apnea-hypopnea suppression on DKD progression is unclear. Objectives: To assess the effect of continuous positive airway pressure (CPAP) on the urinary albumin-to-creatinine ratio (UACR) in patients with DKD and OSA. Methods: In a 52-week, multicentric, open-label, parallel, and randomized clinical trial, 185 patients with OSA and DKD were randomized to CPAP and usual care (n = 93) or usual care alone (n = 92). Measurements and Main Results: UACR, estimated glomerular filtration rate, serum concentrations of creatinine and glycated hemoglobin, insulin resistance, lipid concentrations, sleepiness, and quality of life. A 52-week change in UACR from baseline did not differ significantly between the CPAP group and the usual-care group. However, in per-protocol analyses that included 125 participants who met prespecified criteria for adherence, CPAP treatment was associated with a great reduction in UACR (mean difference, -10.56% [95% confidence interval, -19.06 to -2.06]; P = 0.015). CPAP effect on UACR was higher in nonsleepy patients with more severe OSA, worse renal function, and a more recent diagnosis of DKD. CPAP treatment also improved glycemic control and insulin resistance, as well as sleepiness and health-related quality of life. Conclusions: In patients with OSA and DKD, the prescription of CPAP did not result in a statistically significant reduction in albuminuria. However, good adherence to CPAP treatment in addition to usual care may result in long-term albuminuria reduction compared with usual care alone. Clinical trial registered with www.clinicaltrials.gov (NCT02816762).

Association between positive airway pressure therapy adherence and health care resource utilization in patients with obstructive sleep apnea and type 2 diabetes in the United States

STUDY OBJECTIVES

There is a complex interplay between obstructive sleep apnea (OSA) and type 2 diabetes. There are minimal data regarding the effects of treating OSA with positive airway pressure (PAP) therapy on outcomes and health care resource utilization (HCRU) in patients with OSA and type 2 diabetes. We investigated the impact of PAP adherence on HCRU and costs in this population.

METHODS

A retrospective analysis was conducted with a cohort of OSA patient from a US administrative claims dataset linked to objective device data (AirView, ResMed Corp., San Diego, California). Propensity score matching was used to control for potential imbalance in baseline covariates between PAP-adherent and -nonadherent patients. Newly diagnosed patients with OSA aged ≥ 18 years with type 2 diabetes were included. PAP adherence was defined as meeting Centers for Medicare and Medicaid Services compliance criteria in all 8 90-day periods over 2 years. HCRU was based on the number of all-cause doctor visits, emergency room visits, inpatient hospitalizations, and PAP equipment and supplies.

RESULTS

In years 1 and 2 of PAP therapy, HCRU was significantly lower in adherent vs nonadherent patients (number/patient for emergency room visits 0.68 ± 1.47 vs 0.99 ± 1.91 [year 1], 0.69 ± 1.43 vs 0.95 ± 1.89 [year 2]; for hospitalizations 0.16 ± 0.58 vs 0.22 ± 0.62 [year 1], 0.15 ± 0.51 vs 0.21 ± 0.74 [year 2]; all P < .001). Changes in estimated total 24-month payments were higher for nonadherent patients ($2,282, 95% confidence interval: $1,368, $3,205).

CONCLUSIONS

Consistent use of PAP therapy over 2 years was associated with decreased HCRU in patients with OSA and type 2 diabetes, strongly suggesting a role for screening and treating OSA in type 2 diabetes.

CITATION

Sterling KL, Cistulli PA, Linde-Zwirble W, et al. Association between positive airway pressure therapy adherence and health care resource utilization in patients with obstructive sleep apnea and type 2 diabetes in the United States. J Clin Sleep Med. 2023;19(3):563-571.

The invisible costs of obstructive sleep apnea (OSA): Systematic review and cost-of-illness analysis

BACKGROUND

Obstructive sleep apnea (OSA) is a risk factor for several diseases and is correlated with other non-medical consequences that increase the disease's clinical and economic burden. However, OSA's impact is highly underestimated, also due to substantial diagnosis gaps.

OBJECTIVE

This study aims at assessing the economic burden of OSA in the adult population in Italy by performing a cost-of-illness analysis with a societal perspective. In particular, we aimed at estimating the magnitude of the burden caused by conditions for which OSA is a proven risk factor.

METHODS

A systematic literature review on systematic reviews and meta-analyses, integrated by expert opinion, was performed to identify all clinical and non-clinical conditions significantly influenced by OSA. Using the Population Attributable Fraction methodology, a portion of their prevalence and costs was attributed to OSA. The total economic burden of OSA for the society was estimated by summing the costs of each condition influenced by the disease, the costs due to OSA's diagnosis and treatment and the economic value of quality of life lost due to OSA's undertreatment.

RESULTS

Twenty-six clinical (e.g., diabetes) and non-clinical (e.g., car accidents) conditions were found to be significantly influenced by OSA, contributing to an economic burden ranging from €10.7 to €32.0 billion/year in Italy. The cost of impaired quality of life due to OSA undertreatment is between €2.8 and €9.0 billion/year. These costs are substantially higher than those currently borne to diagnose and treat OSA (€234 million/year).

CONCLUSIONS

This study demonstrates that the economic burden due to OSA is substantial, also due to low diagnosis and treatment rates. Providing reliable estimates of the economic impact of OSA at a societal level may increase awareness of the disease burden and help to guide evidence-based policies and prioritisation for healthcare, ultimately ensuring appropriate diagnostic and therapeutic pathways for patients.

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.

Effect of nocturnal hypoxemia on glycemic control among diabetic Saudi patients presenting with obstructive sleep apnea

BACKGROUND

Obstructive sleep apnea (OSA) is a prevalent disease that is associated with an increased incidence of type II diabetes mellitus (DM) if left untreated. We aimed to determine the association between glycosylated hemoglobin (HbA1c) levels and both nocturnal hypoxemia and apnea-hypopnea index (AHI) among a Saudi patients with OSA.

METHODS

A cross-sectional study that enrolled 103 adult patients diagnosed with DM and confirmed to have OSA by full night attended polysomnography between 2018 and 2021. Those who presented with acute illness, chronic obstructive pulmonary disease (COPD)/restrictive lung diseases causing sleep-related hypoxemia, or no available HbA1c level within 6 months before polysomnography were excluded from the study. Univariate and multivariate linear regression analyses between HbA1c levels and parameters of interest were tested.

RESULTS

Sixty-seven (65%) of the studied population had uncontrolled DM (HbA1c ≥7%). In univariate regression analysis, there was a significant positive association between HbA1c, and sleep time spent with an oxygen saturation below 90% (T90), female gender, and body mass index (BMI) (p<0.05) but not AHI, or associated comorbidities (p>0.05). In the multivariate analysis, HbA1c was positively associated with increasing T90 (p<0.05), and ODI (p<0.05), but not with AHI (p>0.05).

CONCLUSION

Nocturnal hypoxemia could be an important factor affecting glycemic control in patients with OSA suffering from DM irrespective of the severity of both diseases.

Relationship Between Diabetes-Related Complications and Sleep Complaints in Older Mexican Americans

INTRODUCTION/OBJECTIVE

The prevalence of Type 2 Diabetes Mellitus is increasing in the older American population, especially Mexican Americans. Sleep disorders are common in older adults with T2DM. This study examined the relationship between T2DM-related complications and sleep complaints in older Mexican Americans over 9 years of follow-up.

METHODS

Study included 310 participants aged 77 years or older with self-reported diabetes from the Hispanic Established Population for the Epidemiological Study of the Elderly (2007/08-2016).

RESULTS

Of the 310 participants, the mean age was 82.04 years. The cohort had significantly more females (69.03%) than males (30.97%). A substantial number of participants had trouble falling asleep (16.13%), waking up several times (36.45%), trouble staying asleep (15.16%), and feeling tired and worn out after waking up (12.90%). The percent of diabetes complications were 70.2% for circulation problems, 58.2% for eye disorders, 15.9% for kidney disease, and 4.4% for amputation. Participants who experienced sleep complaints for 15 or more days in a month were more likely to experience diabetic complications.

DISCUSSION

This study demonstrated a significant relationship between T2DM macro- and micro-vascular complications and increased risk of sleep disorders in older Mexican Americans.

Validation of the STOP questionnaire as a screening tool for OSA among different populations: a systematic review and meta-regression analysis

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is a sleep breathing disorder associated with adverse health outcomes, but it remains largely underdiagnosed. The STOP questionnaire is a simple tool for screening OSA and is widely used in various populations. The objective of this study was to determine the predictive parameters of the STOP questionnaire to detect OSA in sleep clinics, medical population, surgical population, commercial drivers, and the general population.

METHODS

Electronic databases were searched from January 2008 to April 2021. Pooled predictive parameters were recalculated using 2 × 2 contingency tables and random-effects meta-analyses were performed. The combined test characteristics at different OSA severities [any OSA (AHI≥5), moderate-to-severe OSA (AHI≥15), severe OSA (AHI≥30)] were used to compare the accuracy of the STOP questionnaire with polysomnography. The quality of the studies was evaluated using Cochrane Methods criteria.

RESULTS

Twenty-four studies met the inclusion criteria: 16 were in the sleep clinic population (n=8,132), four in medical population (n=1,023), two in the surgical population (n=258), and one study each on commercial drivers (n=85) and general population (n=4,770). A STOP score ≥2 showed excellent sensitivity to the different OSA severities for the sleep clinic population (>89%) and to severe OSA for the medical population (85.6%). In both populations, the STOP questionnaire also had excellent discriminative power to exclude severe OSA [negative predictive values (NPV) >84%]. The pooled sensitivity and NPV for the surgical population with moderate-to-severe OSA was 81% and 75%.

CONCLUSIONS

This meta-analysis suggests that the STOP questionnaire is a valid and effective screening tool for OSA among these population.

Is kidney a new organ target in patients with obstructive sleep apnea? Research priorities in a rapidly evolving field

The bidirectional relationship between sleep disordered breathing and chronic kidney disease (CKD) has recently gained a lot of interest. Several lines of evidence suggest the high prevalence of coexistent obstructive sleep apnea (OSA) in patients with CKD and end-stage renal disease (ESRD). In addition, OSA seems to result in loss of kidney function in some patients, especially in those with cardio-metabolic comorbidities. Treatment of CKD/ESRD and OSA can alter the natural history of each other; still better phenotyping with selection of appropriate treatment approaches is urgently needed. The aim of this narrative review is to provide an update of recent studies on epidemiological associations, pathophysiological interactions, and management of patients with OSA and CKD or ESRD.

Possible Preventative/Rehabilitative Role of Gliflozins in OSA and T2DM. A Systematic Literature Review-Based Hypothesis

Obstructive sleep apnoea (OSA) is characterized by frequent apnoea episodes during sleep due to upper airway obstruction. The present review summarizes current knowledge on inter-relationships between OSA and type 2 diabetes mellitus (T2DM) and suggests the former as a possible target for sodium-glucose co-transporter-2 inhibitors (SGLT-2i). Based on pathophysiological mechanisms underlying OSA onset and renal SGLT-2 effects, we suggest that SGLT-2i indications might expand beyond current ones, including glucose, lipids, uric acid, blood pressure, and body weight control as well as chronic heart failure and kidney disease prevention.

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.

Impact of inflammatory markers on the relationship between sleep quality and diabetic kidney disease

PURPOSE

Both poor sleep and diabetic kidney disease are closely associated with inflammation. However, the correlation between poor sleep and diabetic kidney disease has not been well clarified. Thus, the aim of this study was to determine the mediating role that inflammatory markers play in the pathogenic effect of poor sleep on the severity of diabetic kidney disease (DKD).

METHODS

A cross-sectional survey was conducted on 336 patients with type 2 diabetes (T2D). DKD was diagnosed according to the guidelines of the National Kidney Foundation-Kidney Disease Outcome Quality Initiative (NKF-K/DOQI). The Pittsburg Sleep Quality Index (PSQI) score was applied to assess patients for the quality of their sleep. Patients with a PSQI score of more than 5 were assigned to the poor sleep group, and the rest of the patients were assigned to the good sleep group. Circulating levels of six inflammatory biomarkers related to poor sleep and DKD were measured.

RESULTS

The prevalence of DKD was higher in patients with poor sleep quality than in those with good sleep quality (42% vs. 25%, P = 0.002). After adjustment, poor sleep quality (PSQI score OR 1.075 [95%CI 1.018-1.135], P = 0.009) remained independently associated with DKD. PSQI score was found to be positively related to fibroblast growth factor (FGF23), interleukin 6 (IL-6), P-selectin, and intercellular adhesion molecule-1 (ICAM-1) (P < 0.01), rather than fibrinogen and C-reactive protein (CRP) in linear regression models. As revealed by multiple mediation analysis, FGF23 and IL-6 mediated 26% and 23% of the relationship between PSQI score and urinary microalbumin (UMA), respectively. Similarly, the FGF23 and ICAM-1, instead of IL-6 and P-selectin, mediated 32% and 24% of the association between PSQI and estimated glomerular filtration rate (eGFR), respectively.

CONCLUSIONS

Poor sleep quality is independently associated with DKD. These results suggest that inflammatory markers contribute to a pathogenic connection between poor sleep and DKD.

Obstructive sleep apnea is associated with impaired renal function in patients with diabetic kidney disease

Obstructive sleep apnea (OSA) is a recognized risk factor for the development of diabetic kidney disease (DKD). Our objectives were to compare the urinary albumin-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) of patients with DKD according to OSA severity, and to evaluate the contribution of sleep parameters to their renal function. In a multicenter, observational, cross-sectional study, 214 patients with DKD were recruited. After a sleep study, UACR and eGFR were measured, as well as serum creatinine, fasting glucose, glycated hemoglobin, insulin resistance, lipid profile and C-reactive protein. UACR was higher in severe OSA patients (920 ± 1053 mg/g) than in moderate (195 ± 232 mg/g, p < 0.001) or mild OSA/non-OSA subjects (119 ± 186 mg/g, p < 0.001). At the same time, eGFR showed an OSA severity-dependent reduction (48 ± 23 vs. 59 ± 21 vs. 73 ± 19 ml/min per 1.73 m², respectively; p < 0.001). Apnea-hypopnea index (AHI and desaturation index (ODI) were identified as independent predictors for UACR and eGFR, respectively. Therefore, in patients with DKD under optimized treatment, severe OSA is associated with a higher UACR and a lower eGFR, reflecting an additional contribution to the impairment of their renal function, although no causality can be inferred.

Obstructive sleep apnea during rapid eye movement sleep in patients with diabetic kidney disease

STUDY OBJECTIVES

Although recent studies suggest that obstructive sleep apnea during rapid eye movement (REM) is associated with different cardiometabolic and neurocognitive risks compared with non-REM (NREM) sleep, there is no information on whether obstructive sleep apnea during REM and/or NREM sleep is independently associated with diabetic kidney disease (DKD).

METHODS

In this cross-sectional study, 303 patients with type 2 diabetes who were followed up at our diabetes outpatient clinic underwent all-night polysomnography. Logistic regression analysis was performed to determine the separate effects of obstructive sleep apnea during REM and/or NREM sleep (REM and/or NREM-apnea-hypopnea index [AHI]) and several other polysomnography parameters on DKD after adjustment for several known risk factors for DKD.

RESULTS

The median (interquartile range) AHI, REM-AHI, and NREM-AHI of the patients (age 57.8 ± 11.8 years, male sex 86.8%, hypertension 64.3%, and DKD 35.2%) were 29.8 (18.0-45.4), 35.4 (21.1-53.3), and 29.1 (16.3-45.4) events/h, respectively. REM-AHI quartiles, but not NREM-AHI quartiles, correlated independently and significantly with DKD (P = .03 for linear trend, odds ratio (OR), and 95% confidence interval for Q2: 3.14 (1.10-8.98), Q3: 3.83 (1.26-11.60), Q4: 4.97 (1.60-15.46), compared with Q1). In addition, categorical AHI (P = .01, OR, and 95% confidence interval for ≥ 15 to < 30: 1.54 (0.64-3.71), ≥ 30: 3.08 (1.36-6.94) compared with < 15), quartiles of AHI (P = .01), quartiles of lowest arterial oxyhemoglobin saturation (P < .01), quartiles of percentage of time spent with arterial oxyhemoglobin saturation < 90 (P < .01), and quartiles of mean arterial oxyhemoglobin saturation were independently associated with DKD.

CONCLUSIONS

Obstructive sleep apnea, especially during REM sleep, is a potential risk factor for DKD.

Multiple, objectively measured sleep dimensions including hypoxic burden and chronic kidney disease: findings from the Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Poor sleep may contribute to chronic kidney disease (CKD) through several pathways, including hypoxia-induced systemic and intraglomerular pressure, inflammation, oxidative stress and endothelial dysfunction. However, few studies have investigated the association between multiple objectively measured sleep dimensions and CKD.

METHODS

We investigated the cross-sectional association between sleep dimensions and CKD among 1895 Multi-Ethnic Study of Atherosclerosis Sleep Ancillary Study participants who completed in-home polysomnography, wrist actigraphy and a sleep questionnaire. Using Poisson regression models with robust variance, we estimated separate prevalence ratios (PR) and 95% CIs for moderate-to-severe CKD (glomerular filtration rate <60 mL/min/1.73 m² or albuminuria >30 mg/g) among participants according to multiple sleep dimensions, including very short (≤5 hours) sleep, Apnoea-Hypopnoea Index and sleep apnoea-specific hypoxic burden (SASHB) (total area under the respiratory event-related desaturation curve divided by total sleep duration, %min/hour)). Regression models were adjusted for sociodemographic characteristics, health behaviours and clinical characteristics.

RESULTS

Of the 1895 participants, mean age was 68.2±9.1 years, 54% were women, 37% were white, 28% black, 24% Hispanic/Latino and 11% Asian. Several sleep metrics were associated with higher adjusted PR of moderate-to-severe CKD: very short versus recommended sleep duration (PR=1.40, 95% CI 1.06 to 1.83); SASHB (Box-Cox transformed SASHB: PR=1.06, 95% CI 1.02 to 1.12); and for participants in the highest quintile of SASHB plus sleep apnoea: PR=1.28, 95% CI 1.01 to 1.63.

CONCLUSIONS

Sleep apnoea associated hypoxia and very short sleep, likely representing independent biological mechanisms, were associated with a higher moderate-to-severe CKD prevalence, which highlights the potential role for novel interventions.

Development and validation of a nomogram for predicting the risk of obstructive sleep apnea in patients with type 2 diabetes

Background

Obstructive sleep apnea (OSA) is highly prevalent among patients with type 2 diabetes mellitus (T2DM) in China, but few patients with clinical symptoms of OSA are referred for diagnostic polysomnography (PSG). Thus, this study aimed to develop and validate an easy-to-use nomogram that predicts the severity of OSA in patients with T2DM.

Methods

This retrospective study included consecutive patients with T2DM admitted to the Endocrinology Department, Third Affiliated Hospital of Soochow University between January 1, 2016 and December 31, 2019. OSA was diagnosed with PSG. Participants were randomly assigned to a training cohort (70%) and a validation cohort (30%). Demographic, anthropometric, and biochemical data were collected. A least absolute shrinkage and selection operator (LASSO) regression model was used to reduce data dimensionality and identify factors for inclusion in the nomogram (training cohort). Nomogram validation was performed in the validation cohort.

Results

The study included 280 participants in the training group and 118 participants in the validation group. OSA prevalence was 58.5%. LASSO regression identified waist-to-hip ratio (WHR), smoking status, body mass index (BMI), serum uric acid (UA), the homeostasis model assessment insulin resistance index (HOMA-IR), and history of fatty liver disease as predictive factors for inclusion in the nomogram. Discrimination and calibration in the training group (C-index =0.88) and validation group (C-index =0.881) were good. The nomogram identified patients with T2DM at risk for OSA with an area under the curve of 0.851 [95% confidence interval (CI), 0.788-0.900].

Conclusions

Our nomogram could be used to facilitate individualized prediction of OSA risk in patients with T2DM and help prioritize patients for diagnostic PSG.

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.

Correlation Between QTc Prolongation and Obstructive Sleep Apnea in Patients with Type 2 Diabetes Mellitus

BACKGROUND Obstructive sleep apnea (OSA) plays an important role in the progression of cardiovascular disease (CVD), and is a common symptom in patients with type 2 diabetes mellitus (T2DM). Prolongation of corrected QT interval (QTc) reflects ventricular arrhythmias and CVD. The aim of this study was to explore the relationship between OSA and QTc in T2DM patients and to evaluate the potential application of QTc in clinical practice. MATERIAL AND METHODS A total of 358 T2DM patients were involved in this study. OSA was diagnosed with apnea-hypopnea index ≥5 by full-night polysomnography and QTc was measured by a 12-lead electrocardiogram (ECG). Patients were grouped into 2 groups based on median QTc, and clinical data were studied. Logistic regression analysis was used to investigate the association between OSA and QTc with adjusted age, sex, body mass index (BMI), hypertension, total bilirubin (TBL), and smoking history. RESULTS Among 358 T2DM patients, 59.2% had OSA. Compared to those in the QTc <418 ms group, older patients, females, patients with higher BMI, and OSA patients in the QTc ≥418 ms group were more likely to have OSA (p<0.05). Correlation analysis suggested that OSA was associated with longer QTc (OR: 2.355, 95% CI: 1.529-3.626, p<0.001). For T2DM patients with QTc ≥418 ms, older patients (OR: 1.042, 95% CI: 1.042-1.064, p<0.001), females (OR: 2.36, 95% CI: 1.371-4.063, p<0.01), and patients with higher BMI (OR: 1.113, 95% CI: 1.037-1.195, p<0.01) were significantly more likely to have OSA. CONCLUSIONS In this cross-sectional study, we found that the presence and severity of OSA was associated with QTc prolongation in 358 patients with T2DM, and age, female sex, and BMI appear to be independent risk factors for OSA and CVD.

Associations of apnea hypopnea index and educational attainments with microvascular complications in patients with T2DM

PURPOSE

The relationship between obstructive sleep apnea (OSA) and diabetic microvascular complications (DMC) are controversial. Whether low education is associated with increased risk of DMC independently of poor lifestyles are currently unknown. The aim of this study is to explore the independent associations of different PSG index and educational attainment with risks of DR, DKD, and DPN.

METHODS

A cross-sectional study of 330 patients with T2DM who underwent overnight polysomnography (PSG) tests. Multivariable logistic regression analysis was performed to determine the associations of PSG index and educational attainments with DR, DKD, and DPN.

RESULTS

The prevalence rates of DMC were 30.6% for DR, 24.9% for DKD, and 64.6% for DPN. All PSG index (AHI, REM-AHI, NREM-AHI, the severity of OSAS, ODI, MAI, and lowest SaO₂) were not significantly associated with risks of DR, DKD, or DPN with adjustment for potential confounding factors. Subjects with increasing educational attainments showed significantly decreased prevalence rates of DR (42.6, 27.3, and 21.3%, p = 0.005), DKD (31.7, 25.3, and 14.7%, p = 0.035) and DPN (74.3, 63.6, and 53.3%, p = 0.015), respectively. Logistic regression analyses showed that educational attainment of primary or below showed significantly increased risks of DR (OR (95% CIs): 3.596 (1.453-8.899, p = 0.006)) and DKD (OR (95% CIs): 3.201 (1.244-8.242, p = 0.016)) as compared with that of college or above. There were significant trends of lower educational attainment with increased risks of DR and DKD (p values < 0.05).

CONCLUSION

PSG index were not significantly associated with DMC. But lower education was significantly associated with increased risks of DR and DKD, and strategies to prevent DMC for those with low education should be strengthened.

Male Patients on Peritoneal Dialysis Have a Higher Risk of Sleep Apnea

STUDY OBJECTIVES

Peritoneal dialysis (PD) is a renal replacement therapy. One concern is whether patients on PD have a higher risk of sleep apnea (SA) due to intra-abdominal pressure increase and worsened ultrafiltration capacity. Despite this concern, to date, whether the risk of SA differs between PD, hemodialysis (HD), and groups without uremia is still uncertain.

METHODS

In this retrospective cohort study, data were obtained from the National Health Insurance Research Database of Taiwan. This database enrolled almost all patients on dialysis in the country. A total of 7,645 incident patients on PD and 38,225 incident patients on HD were enrolled. In addition, 38,225 patients without uremia were selected as the comparison cohort. Individuals were monitored for the occurrence of SA until 2013.

RESULTS

The results showed that patients on PD, regardless of sex, all had a higher risk of SA than non-dialysis groups. In contrast, the risk of SA in patients on HD was not significantly different from that of patients without uremia. We also compared the risk of SA between patients on PD and HD directly. The results showed that male patients on PD had a significantly higher risk of SA risk than male patients on HD. However, the risk of SA did not differ between female patients on PD and HD.

CONCLUSIONS

Patients on PD should receive regular SA assessments and that an increased awareness and a higher index of suspicion for SA should be maintained in these patients, especially male patients.

Chronic kidney disease in patients with obstructive sleep apnea. A narrative review

Prevalence of both chronic kidney disease (CKD) and obstructive sleep apnea (OSA) is continuously increasing. Moreover, the prevalence of OSA increases as kidney function declines and is higher among patients with end-stage renal disease (ESRD). In addition, OSA is recognized as a potential nontraditional risk factor for development and progression of CKD. Continuous positive airway pressure (CPAP) plays a pivotal role in the management of OSA, eliminating patients' symptoms and improving their quality of life. Recent studies suggested that CPAP treatment may have beneficial effects on kidney function among patients with OSA. This narrative review summarizes the existing knowledge on the association between CKD and OSA, with emphasis on the epidemiology, the pathophysiology of the development of CKD in OSA and vice versa, as well as the effect of CPAP on renal function.

Risk of Incident Obstructive Sleep Apnea Among Patients With Type 2 Diabetes

OBJECTIVE

This study compared the incidence of obstructive sleep apnea (OSA) in patients with and without type 2 diabetes and investigated risk factors for OSA in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

A retrospective cohort study was performed to compare OSA incidence between adult patients with and without type 2 diabetes matched for age, sex, and BMI. Patients with a prevalent OSA diagnosis were excluded. The study cohort was derived from The Health Improvement Network (THIN), a U.K. primary care database, from 1 January 2005 to 31 December 2017.

RESULTS

There were 3,110 (0.88%) and 5,968 (0.46%) incident OSA cases identified in the 360,250 exposed and 1,296,489 unexposed patient cohorts, respectively. Adjusted incidence rate ratio (aIRR) of OSA in patients with type 2 diabetes compared with those without was 1.48 (95% CI 1.42-1.55; P < 0.001). In a multivariate regression analysis of patients with type 2 diabetes, significant predictors of OSA were diabetes-related foot disease (1.23 [1.06-1.42]; P = 0.005), being prescribed insulin in the last 60 days (1.58 [1.42-1.75]; P < 0.001), male sex (2.27 [2.09-2.46]; P < 0.001), being overweight (2.02 [1.54-2.64]; P < 0.001) or obese (8.29 [6.42-10.69]; P < 0.001), heart failure (1.41 [1.18-1.70]; P < 0.001), ischemic heart disease (1.22 [1.11-1.34]; P < 0.001), atrial fibrillation (1.23 [1.04-1.46]; P = 0.015), hypertension (1.32 [1.23-1.43]; P < 0.001), and depression (1.75 [1.61-1.91]; P < 0.001).

CONCLUSIONS

When considered alongside previous evidence, this study indicates that the association between type 2 diabetes and OSA is bidirectional. In addition to known predictors of OSA, diabetes-related foot disease and insulin treatment were identified as risk factors in patients with type 2 diabetes.

Obstructive sleep apnea and comorbidities: a dangerous liaison

Obstructive sleep apnea (OSA) is a highly prevalent disease, and is traditionally associated with increased cardiovascular risk. The role of comorbidities in OSA patients has emerged recently, and new conditions significantly associated with OSA are increasingly reported. A high comorbidity burden worsens prognosis, but some data suggest that CPAP might be protective especially in patients with comorbidities. Aim of this narrative review is to provide an update on recent studies, with special attention to cardiovascular and cerebrovascular comorbidities, the metabolic syndrome and type 2 diabetes, asthma, COPD and cancer. Better phenotypic characterization of OSA patients, including comorbidities, will help to provide better individualized care. The unsatisfactory adherence to CPAP in patients without daytime sleepiness should prompt clinicians to examine the overall risk profile of each patient in order to identify subjects at high risk for worse prognosis and provide the optimal treatment not only for OSA, but also for comorbidities.

Effect of Sleep-Disordered Breathing on Albuminuria in 273 Patients With Type 2 Diabetes

STUDY OBJECTIVES

Sleep-disordered breathing (SDB) can induce hyperglycemia, hypertension, and oxidative stress, conditions that are known to cause kidney damage. Therefore, SDB may exacerbate albuminuria, which is an established marker of early-stage kidney damage in patients with type 2 diabetes mellitus (T2DM). The association between SDB and albuminuria in patients with T2DM was investigated in this study.

METHODS

This cross-sectional study included 273 patients with T2DM who underwent portable sleep testing and measurement of urine albumin to creatinine ratio (UACR). The association between the severity of SDB and albuminuria was investigated. Patients were divided into three groups according to the respiratory event index (REI): the no or mild group (REI < 15 events/h), moderate (REI 15 to < 30 events/h), and severe (REI ≥ 30 events/h). Albuminuria was defined as UACR ≥ 3.4 mg/mmol creatinine. Logistic regression analysis for albuminuria included the categorical REI as the independent variable.

RESULTS

The median (interquartile range) REI of all patients (age 57.9 ± 11.9 years, mean ± standard deviation, male sex 81.7%, body mass index 26.7 [24.2-29.5] kg/m², estimated glomerular filtration rate 82 [65-97] mL/min/1.73 m²) was 13.0 (7.0-24.2) events/h. The REI, as a categorical variable, was significantly associated with albuminuria after adjustment for other risk factors for albuminuria; REI 15 to < 30 events/h: odds ratio (OR) 3.35, 95% confidence interval (95% CI), 1.68-6.67, P < .001; REI ≥ 30: OR 8.52, 95% CI, 3.52-20.63, P < .001). In addition, the natural logarithm-transformed REI of all patients also correlated significantly with albuminuria.

CONCLUSIONS

The severity of SDB is associated with albuminuria in patients with T2DM.

Update of pathophysiology and management of diabetic kidney disease

Diabetic kidney disease (DKD) is a major cause of morbidity and mortality in patients with diabetes mellitus and the leading cause of end-stage renal disease in the world. The most characteristic marker of DKD is albuminuria, which is associated with renal disease progression and cardiovascular events. Renal hemodynamics changes, oxidative stress, inflammation, hypoxia and overactive renin-angiotensin-aldosterone system (RAAS) are involved in the pathogenesis of DKD, and renal fibrosis plays the key role. Intensified multifactorial interventions, including RAAS blockades, blood pressure and glucose control, and quitting smoking, help to prevent DKD development and progression. In recent years, novel agents are applied for preventing DKD development and progression, including new types of glucose-lowering agents, pentoxifylline, vitamin D analog paricalcitol, pyridoxamine, ruboxistaurin, soludexide, Janus kinase inhibitors and nonsteroidal minerocorticoid receptor antagonists. In this review, recent large studies about DKD are also summarized.

Sleep Duration and Diabetic Kidney Disease

Aims: Abnormally short or long durations of sleep have been proposed as a risk factors for diabetes and its micro- and macro-vascular complications. However, the relationship between sleep duration and diabetic kidney disease (DKD) has not been well-characterized. Thus, we aimed to examine the association of sleep duration with DKD in two Asian populations. Methods: We included 1,258 persons (Malay, n = 403; Indian, n = 855) aged 40-80 years with diabetes from a population-based cross-sectional sample from Singapore. DKD was defined by low estimated glomerular filtration rate (eGFR <60 mL/min/1.73 m²) and albuminuria (urinary albumin-to-creatinine ratio ≥30 mg/g, only measured in Indian participants). Self-reported habitual sleep duration was categorized into 4 categories: very short (<5 h), short (5-6.9 h), normal (7-8 h) and long (>8 h). The associations of sleep duration with low eGFR and albuminuria were analyzed using multivariable logistic regression models adjusted for multiple potential confounders (including classic risk factors such as HbA1c and hypertension). Results: In total, 268 (21.3%) participants had low eGFR, and 271 (34.7% in Indians) had albuminuria. The number (%) of individuals with very short, short, normal, and long durations of sleep were 117 (9.3%), 629 (50.0%), 429 (34.1%), and 83 (6.6%), respectively. Long sleep duration was associated with a higher odds of renal insufficiency compared to normal sleep duration (OR [95% CI]: 2.31 [1.27-4.19]) on multivariable analysis. Similarly, both long and very short durations of sleep were associated with higher odds of albuminuria (OR [95%]: 2.44 [1.36, 4.38] and 2.37 [1.25, 4.50], respectively) in Indian participants (where data on albuminuria were available). Conclusions: Our study suggests that abnormally short or long durations of sleep were associated with DKD, manifesting as either a reduced eGFR or increased albuminuria. However, further longitudinal data would be required for confirmation.

The Relationship between Diabetes-Related Complications and Obstructive Sleep Apnea in Type 2 Diabetes

This study explored the relationship between obstructive sleep apnea (OSA) and the presence of any diabetes-related complications in type 2 diabetes and whether this was mediated by hypertension. Secondly, the relationship between OSA severity and estimated glomerular filtration rate (eGFR) was investigated. A total of 131 patients participated. OSA was diagnosed using a home monitor, and severity was measured by apnea-hypopnea index (AHI) and oxygen desaturation index (ODI). OSA was found in 75.6% of the participants, 40.5% with moderate-to-severe degree. Any diabetes-related complications (retinopathy, neuropathy, nephropathy, or coronary artery disease) were present in 55.5%, and 70.2% of the participants had hypertension. Mediation analysis indicated that, compared to those with mild or no OSA, those with moderate-to-severe OSA were 3.05 times more likely to have any diabetes-related complications and that this relationship was mediated by the presence of hypertension. After adjusting for confounders, ODI (B = -0.036, p = 0.041), but not AHI, was significantly associated with lower eGFR. In conclusion, moderate-to-severe OSA was related to the presence of any diabetes-related complications in type 2 diabetes, and the relationship was mediated by hypertension. The severity of intermittent hypoxia was associated with lower eGFR. Whether OSA treatment will delay or reduce diabetes-related complications should be investigated.

Association of obstructive sleep apnoea with the risk of vascular outcomes and all-cause mortality: a meta-analysis

OBJECTIVE

This study aimed to conduct a meta-analysis to explore and summarise the evidence regarding the association between obstructive sleep apnoea (OSA) and the subsequent risk of vascular outcomes and all-cause mortality.

METHODS

Electronic databases PubMed, Embase and the Cochrane Library were searched to identify studies conducted through May 2016. Prospective cohort studies that reported effect estimates with 95% CIs of major adverse cardiac events (MACEs), coronary heart disease (CHD), stroke, cardiac death, all-cause mortality and heart failure for different levels versus the lowest level of OSA were included.

RESULTS

A total of 16 cohort studies reporting data on 24 308 individuals were included. Of these, 11 studies reported healthy participants, and the remaining five studies reported participants with different diseases. Severe OSA was associated with an increased risk of MACEs (relative risk (RR): 2.04; 95% CI 1.56 to 2.66; P<0.001), CHD (RR: 1.63; 95% CI 1.18 to 2.26; P=0.003), stroke (RR: 2.15; 95% CI 1.42 to 3.24; P<0.001), cardiac death (RR: 2.96; 95% CI 1.45 to 6.01; P=0.003) and all-cause mortality (RR: 1.54; 95% CI 1.21 to 1.97; P<0.001). Moderate OSA was also significantly associated with increased risk of MACEs (RR: 1.16; 95% CI 1.01 to 1.33; P=0.034) and CHD (RR: 1.38; 95% CI 1.04 to 1.83; P=0.026). No significant association was found between mild OSA and the risk of vascular outcomes or all-cause mortality (P>0.05). Finally, no evidence of a factor-specific difference in the risk ratio for MACEs among participants with different levels of OSA compared with those with the lowest level of OSA was found.

CONCLUSIONS

Severe and moderate OSAs were associated with an increased risk of vascular outcomes and all-cause mortality. This relationship might differ between genders. Therefore, further large-scale prospective studies are needed to verify this difference.

The association of obstructive sleep apnea and renal outcomes-a systematic review and meta-analysis

BACKGROUND

The aim of this systematic review and meta-analysis was to summarize the association of obstructive sleep apnea (OSA) with renal outcome.

METHODS

Our study followed the PRISMA guidelines. Two independent reviewers searched for relevant articles in the databases of Pubmed, the Web of Science and CENTRAL, and conducted study selection and quality assessment. A random-effect model was used to estimate the effects.

RESULTS

total of 1240 articles were initially identified (Pubmed = 568, Web of Science = 640, CENTRAL = 32). After removal of duplicate articles (n = 415) and irrelevant articles (n = 788), 37 were selected for full-text review, and 18 were finally included in the analysis. Overall, patients diagnosed with OSA were found to have a higher odds ratio (OR) of a poorer renal outcome, with a pooled OR of 1.77 (95% C.I.: 1.37–2.29). The significant association between OSA and a poorer renal outcome was not affected by the medical condition of diabetes mellitus (DM). In addition, we found that OSA was consistently associated with higher albuminuria/proteinuria and a lower estimated glomerular filtration rate (eGFR), with a pooled OR of 1.84 (95% C.I.: 1.24–2.73) and 1.60 (95% C.I.: 1.19–2.16), respectively. A greater OSA severity was also found to be related to a higher OR, with a mild group OR of 1.45 (95% C.I.: 1.19–1.77) and a moderate and severe group OR of 2.39 (95% C.I.: 1.96–2.90).

CONCLUSIONS

Our study demonstrated that OSA is significantly associated with poorer renal function.

Obstructive Sleep Apnea and Diabetic Nephropathy

Obstructive sleep apnea (OSA), a condition with important implications for hypertension, diabetes, and cardiovascular disease, has been less researched for diabetes-associated microvascular disease. Such research is particularly important for developing countries (in particular, China and India), which are showing rapidly increasing prevalence of obesity, diabetes, and diabetic nephropathy (DN). In particular, independent association between OSA and DN needs more research inputs, keeping commonalty of risk factor profile for both diseases in mind. Finally, although weight loss remains the most effective strategy for OSA and also to some extent for DN, whether treatment with continuous positive airway pressure improves DN, similar to its positive effects on insulin resistance and glucose metabolism, remains to be established.

Sleep Apnea in Type 2 Diabetes

IN BRIEF Obstructive sleep apnea (OSA) alters glucose metabolism, promotes insulin resistance, and is associated with development of type 2 diabetes. Obesity is a key moderator of the effect of OSA on type 2 diabetes. However, chronic exposure to intermittent hypoxia and other pathophysiological effects of OSA affect glucose metabolism directly, and treatment of OSA can improve glucose homeostasis.

Sleep Optimization and Diabetes Control: A Review of the Literature

Pre-diabetes and diabetes occur secondary to a constellation of pathophysiological abnormalities that culminate in insulin resistance, which results in reduced cellular glucose uptake and increased glucose production. Although pre-diabetes and diabetes have a strong genetic basis, they are largely environmentally driven through lifestyle factors. Traditional lifestyle factors such as diet and physical activity do not fully explain the dramatic rise in the incidence and prevalence of diabetes mellitus. Sleep has emerged as an additional lifestyle behavior, important for metabolic health and energy homeostasis. In this article, we review the current evidence surrounding the sleep-diabetes association.