Cardiovascular consequences of obese and nonobese obstructive sleep apnea

Association of Obstructive Sleep Apnea on Heart Failure and Its Risk Factors: A Two-Step Mendelian Randomization Study

INTRODUCTION

Recent studies have indicated that obstructive sleep apnea (OSA) is linked to a higher likelihood of heart failure (HF). However, the causal connection between the two conditions is uncertain. We aimed to investigate the causal association of OSA with HF and its risk factors.

METHODS

The OSA summary statistics are derived from the FinnGen database, including 38,998 cases and 336,659 controls. HF summary statistics come from HERMES, the UK Biobank, and the FinnGen database. A two-sample mendelian randomization (MR) analysis was conducted to examine the causality of OSA on HF risk. Furthermore, the mediator effect of potential risk factors was assessed by a two-step MR.

RESULTS

The results of MR analysis demonstrated that genetically determined OSA is causal associated with the higher likelihood of HF (HERME: odds ratio [OR] = 1.222; 95% confidence interval [CI]: 1.091, 1.369; p = 5.19 × 10-4) (FinnGen: OR = 1.233; 95% CI: 1.129, 1.346; p = 3.32 × 10-6) (UK Biobank: OR = 1.002; 95% CI: 1.000, 1.003; p = 0.014). Two-step MR analysis indicated that obesity, blood glucose, depression, and other CVDs have significant mediating effects on the causal effect between OSA and HF.

CONCLUSION

This MR study emphasizes the causal effect of OSA on HF risk. Adiposity traits play a major role in the process of OSA leading to HF. Considering the detrimental impact of OSA on HF, it becomes imperative to prioritize the prevention and management of HF in individuals afflicted with OSA. The foremost intervention strategy should revolve around effective obesity management.

Prognostic Implications of OSA in Acute Coronary Syndrome by Obesity Status

BACKGROUND

A close relationship exists between OSA and obesity. The impact of obesity on the prognostic significance of OSA in patients with acute coronary syndrome (ACS) remains unclear.

RESEARCH QUESTION

Do the effects of OSA on subsequent cardiovascular events in patients with ACS vary with obesity status?

STUDY DESIGN AND METHODS

This is a prospective cohort study. Patients 18 to 85 years of age and hospitalized for ACS were consecutively enrolled and underwent portable sleep monitoring after clinical stabilization. OSA was defined as an apnea hypopnea index ≥ 15 events/h. The primary end point was major adverse cardiovascular and cerebrovascular event (MACCE), including cardiovascular death, hospitalization for ACS, stroke, ischemia-driven revascularization, or hospitalization for heart failure.

RESULTS

Among 1,920 patients enrolled (84.5% men; mean age ± SD, 56.4 ± 10.5 years), 1,013 (52.8%) had OSA, and 718 (37.4%) were obese (BMI ≥ 28 kg/m²). During 2.9 years (1.5, 3.6) follow up, the incidence of MACCE was significantly higher in patients with obesity than in patients without obesity (hazard ratio [HR], 1.29; 95% CI, 1.06-1.58; P = .013). Although the prevalence of OSA was lower in patients without obesity than in those with obesity (43.9% vs 67.5%, P < .001), OSA independently predicted the incidence of MACCE only in patients without obesity (adjusted HR, 1.34; 95% CI, 1.03-1.75; P = .03), but not in patients with obesity (adjusted HR, 1.10; 95% CI, 0.78-1.55; P = .58). No significant interaction between obesity and OSA was noted (P for interaction = .35). The incremental risk associated with OSA in patients without obesity might be explained by more hospitalization for ACS and ischemia-driven revascularization.

INTERPRETATION

For patients with ACS, OSA was independently associated with an increased risk of subsequent events, particularly among patients without obesity. These findings highlight the importance of identifying OSA in nonobese patients with ACS.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT03362385; URL: www.

CLINICALTRIALS

gov.

Impact of sleep apnea and treatments on cardiovascular disease

Cardiovascular diseases (CVDs) are the leading causes of mortality worldwide, accounting for nearly 18 million deaths per year. Among other considerations, treating CVDs requires better understanding their risk factors. Sleep-disordered breathing, especially obstructive sleep apnea (OSA), is a likely contributor to several CVDs. We review key epidemiological data that addresses the link between OSA and cardiovascular outcomes such as hypertension, atrial fibrillation (AF), stroke, atherosclerosis, and heart failure (HF), and proposed pathophysiological mechanisms underlying this association. There are several biological pathways linking OSA and an increased propensity to cardiovascular diseases, and we discuss the evidence on the benefits of treatments of OSA on the prevalence of cardiovascular complications.

Respiratory disorders of Parkinson's disease

Parkinson's disease (PD) is characterized by the progressive loss of dopaminergic neurons in the substantia nigra, mainly affecting people over 60 yr of age. Patients develop both classic symptoms (tremors, muscle rigidity, bradykinesia, and postural instability) and nonclassical symptoms (orthostatic hypotension, neuropsychiatric deficiency, sleep disturbances, and respiratory disorders). Thus, patients with PD can have a significantly impaired quality of life, especially when they do not have multimodality therapeutic follow-up. The respiratory alterations associated with this syndrome are the main cause of mortality in PD. They can be classified as peripheral when caused by disorders of the upper airways or muscles involved in breathing and as central when triggered by functional deficits of important neurons located in the brainstem involved in respiratory control. Currently, there is little research describing these disorders, and therefore, there is no well-established knowledge about the subject, making the treatment of patients with respiratory symptoms difficult. In this review, the history of the pathology and data about the respiratory changes in PD obtained thus far will be addressed.

Time-dependence and comparison of regional and overall anthropometric features between Asian and Caucasian populations with obstructive sleep apnea: a cumulative meta-analysis

Background

Anthropometric measurements are simple and reachable tools for self-evaluating and screening patients with a high risk of obstructive sleep apnea (OSA). However, the accumulated relationship of obesity on the anthropometric characteristics of OSA is not well understood. The aim of the study was to show the time-dependent trend of OSA patients and compare overall and regional anthropometric between two ethnicities.

Methods

A cumulative meta-analysis was performed to assess obesity metrics in patients with and without OSA between Asians and Caucasians. We searched PubMed, Web of Science, Embase, and Scopus up to Jun 2020. Included studies used body mass index (BMI), neck circumference (NC), waist circumference (WC) and waist-to-hip ratio (WHR) as measures of anthropometric features in the adult OSA population and controls, utilized in-lab polysomnography or home sleep testing with apnea-hypopnea index (AHI) or respiratory disturbance index (RDI) classification, reported ethnicity/race, and were published in English. Any studies lacking one of these criteria or sufficient data were excluded.

Results

Forty studies with a total of 19,142 subjects were investigated. Comparison of changes between patients with and without OSA showed that OSA patients had a higher BMI [mean difference (MD) 3.12, 95% confidence interval (CI): 2.51–3.73], NC (MD 3.10, 95% CI: 2.70–3.51), WC (MD 9.84, 95% CI: 8.42–11.26) and waist-hip ratio (MD 0.04, 95% CI: 0.03–0.05) than the control subjects. The accumulated time-dependent increase in population with OSA was significantly apparent with all anthropometric features. BMI increased from 2000 (MD 0.50) to 2012 (MD 3.08–3.48) and remained stable afterwards (MD 2.70–3.17), NC increased from 2000 (MD 0.40) to 2013 (MD 3.09) and remained stable afterwards too (MD 3.06–3.21). WC increased from 2000 (MD 2.00) to 2012 (MD 9.37–10.03) and also remained stable afterwards (MD 8.99–9.84). WHR was stable from 2000 to 2004 with an MD of 0.01 and then stable from 2007 onwards with an increased MD of 0.03–0.04. Compared with Caucasian patients, Asian patients had lower obesity relevant variates.

Conclusions

BMI, NC, WC and WHR are associated with OSA in both ethnic groups. Anthropometry for overall and regional obesity could facilitate differentiation of patients with OSA from individuals without OSA by ethnicity.

Obstructive Sleep Apnea in Children and Adolescents and the Risk of Major Adverse Cardiovascular Events: A Nationwide Cohort Study in Taiwan

STUDY OBJECTIVES

This study has investigated the risk of major adverse cardiovascular events (MACEs), including acute myocardial infarction, coronary artery disease, peripheral artery disease, and acute stroke, among children and adolescents (age younger than 20 years) with obstructive sleep apnea (OSA).

METHODS

In this study, the population-based National Health Insurance Research Database of Taiwan was used to identify patients in whom OSA had been first diagnosed between 2000 and 2015. Children and adolescents with OSA (n = 6,535) were included with 1:3 ratio by age, sex, and index year of control participants without OSA (n = 19,605). The Cox proportional regression model was used to evaluate the risk of MACEs in this cohort study.

RESULTS

After a 15-year follow-up, the incidence rate of MACEs was higher in the OSA cohort when compared with the non-OSA control cohort (15.97 and 8.20 per 100,000 person-years, respectively). After adjusting for covariates, the risk of MACEs among children and adolescents with OSA was still significantly higher (hazard ratio = 2.050; 95% confidence interval = 1.312-3.107; P = .010). No MACEs were found in the children and adolescents with OSA who received continuous airway positive pressure treatment or pharyngeal surgery.

CONCLUSIONS

This study found a significantly higher risk of MACEs in children and adolescents with OSA. These findings strongly suggest that clinicians should provide careful follow-up and medical treatment for children and adolescents with OSA.

Intermittent hypoxia in utero damages postnatal growth and cardiovascular function in rats

Obstructive sleep apnea (OSA) is common in pregnancy and may compromise fetal and even postnatal development. We developed an animal model to determine if maternal OSA could have lasting effects in offspring. Pregnant Sprague-Dawley rats were exposed to reduced ambient O₂ from 21 to 4-5%, approximately once per minute [chronic intermittent hypoxia (CIH)] for 8 h/day during gestation days 3-19. Similarly handled animals exposed to ambient air served as controls (HC). Offspring were studied for body growth and cardiovascular function for 8 postnatal weeks. Compared with HC, prenatal CIH led to growth restriction, indicated by smaller body weight and tibial length, and higher arterial blood pressure in both male and female offspring. Compared with same-sex HC, CIH males showed abdominal obesity (greater ratio of abdominal fat weight to body weight or tibial length), left ventricular (LV) hypertrophy (greater heart weight-to-tibial length ratio and LV posterior wall diastolic thickness), elevated LV contractility (increases in LV ejection fraction, end-systolic pressure-volume relations, and preload recruitable stroke work), elevated LV and arterial stiffness (increased end-diastolic pressure-volume relationship and arterial elasticity), and LV oxidative stress (greater lipid peroxide content). Compared with female CIH offspring, male CIH offspring had more profound changes in blood pressure (BP), cardiac function, myocardial lipid peroxidase (LPO) content, and abdominal adiposity. Rodent prenatal CIH exposure, mimicking human maternal OSA, exerts detrimental morphological and cardiovascular effects on developing offspring; the model may provide useful insights of OSA effects in humans. NEW & NOTEWORTHY Obstructive sleep apnea is common in human pregnancy. Following maternal exposure to chronic intermittent hypoxia, a hallmark of sleep apnea, both sexes of rat offspring showed growth retardation, with males being more vulnerable to hypertension and dysfunctional left ventricular changes. This model is useful to study detrimental effects of maternal obstructive sleep apnea on developing offspring in humans.

Definition and Importance of Autonomic Arousal in Patients with Sleep Disordered Breathing

Autonomic arousal at the end of sleep apnea events are not well-explored. We prospectively studied 20 patients with obstructive sleep apnea (OSA) and 24 healthy volunteers for 2 nights with cardiorespiratory polysomnography and continuous noninvasive blood pressure (Portapres). Recordings were scored visually for cortical and autonomic arousal. In the OSA group, 2151 cortical arousals and in the controls 1089 cortical arousals were scored. Respiratory arousal caused most frequently an increase of highest mean arterial blood pressure in patients and controls. A useful definition for autonomic arousal for OSA and controls based on blood pressure and heart rate analysis was developed.

Obstructive sleep apnea in adult patients: considerations for anesthesia and acute pain management

Obstructive sleep apnea (OSA) represents a challenge in the perioperative period for both physicians and the health care system alike. A number of studies have associated OSA with increased risk for postoperative complications. This is of particular concern in the face of this disease remaining vastly underdiagnosed. In this context, current guidelines and established concepts such as the use of continuous positive airway pressure or the level of postoperative monitoring, lack strong scientific evidence. Other interventions such as the use neuraxial/regional anesthesia may however offer added benefit. This review aims to address considerations for physicians in charge of OSA patients in the perioperative setting and to give an outlook for current and future research on this topic.

A comparative study on the clinical and polysomnographic pattern of obstructive sleep apnea among obese and non-obese subjects

OBJECTIVE:

This study was designed to compare the pattern of obstructive sleep apnea (OSA) among obese and nonobese subjects regarding clinical and polysomnographic data obtained for a polysomnographic study.

METHODS:

A cross-sectional retrospective descriptive study was conducted by analyzing polysomnographic data in 112 consecutive patients underwent a sleep study at our sleep laboratory from January 2009 to July 2010. Out of them, 81 were diagnosed to have OSA (apnea-hypopnoea Index ≥5). These patients were classified in two groups with body mass index (BMI) < 27.5 kg/m² as nonobese and BMI≥27.5 kg/m² as obese. Clinical as well as polysomnographic data were evaluated and compared between the two groups. Patients were also evaluated for other risk factors such as smoking, alcoholism, and use of sedatives. Data were subjected to statistical analysis (χ²-test, P value <0.05 considered to be significant). The Fisher Exact test was applied wherever the expected frequency for a variable was ≤5.

RESULTS:

Of 81 patients with OSA, 36 (44.4%) were nonobese with a mean BMI of 26.62 ± 2.29 kg/m² and 45 (55.6%) were obese with a mean BMI of 35.14 ± 3.74 kg/m². Mean AHI per hour was significantly more in the obese than in the nonobese group (50.09 ± 29.49 vs. 24.36 ± 12.17, P<0.001). The use of one or more sedatives was more in nonobese as compared to obese (58.3% vs. 24.4%, P=0.002). The obese group had significantly higher desaturation and arousal index (P<</i>0.001). The minimal oxygen saturation was lower in the obese than the nonobese group (68.5 ± 13.00 vs. 80.3 ± 7.40, P<</i>0.001) and was well below 90% in both groups. Overall, the OSA in nonobese patients was mild-to-moderate as compared to that of the obese and no significant differences were observed between them as regard to age, gender, mean neck circumference, excessive daytime sleepiness, adenoid or tonsillar enlargement, smoking, and remaining polysomnographic parameters.

CONCLUSION:

Obstructive sleep apnea can occur in nonobese persons though with less severity as compared to obese leading to a concept that OSA is not restricted to obese persons only and there is a high demand of its awareness regarding evaluation, diagnosis, and management in such individuals.

Metabolic syndrome correlates intracoronary stenosis detected by multislice computed tomography in male subjects with sleep-disordered breathing

BACKGROUND

Sleep-disordered breathing (SDB), especially obstructive sleep apnea (OSA), has frequent complications include hypertension, dyslipidemia and insulin resistance based on abdominal obesity or excess visceral fat (called Syndrome Z). OSA is a potential risk factor for cardiovascular diseases. The clinical characteristics of Japanese OSA subjects with OSA remain unclear. The present study investigated prevalence and predictive factors of intracoronary stenosis detected by multislice computed tomography (MSCT) in Japanese male subjects with SDB/OSA.

FINDINGS

The study (O-VFStudy) subjects were 39 Japanese men with SDB/OSA who underwent all-night cardiorespiratory monitoring with fully attended polysomnography, and moreover both fat computed tomography (CT) scan and 64-row MSCT coronary angiography. The prevalence of coronary stenosis in this selected population with SDB/OSA was 15%. Logistic regression analysis showed a significant relationship between age-adjusted CAD and metabolic syndrome (p < 0.05), but not serum adiponectin levels and nocturnal fall in adiponectin. Subjects with the metabolic syndrome had significantly higher prevalence of CAD (31.3 versus 4.3%, p = 0.033), and lower levels of serum adiponectin (4.5 ± 0.6 versus 6.4 ± 0.6 μg/mL, p = 0.014), compared with groups without the metabolic syndrome.

CONCLUSIONS

The present study describes that the prevalence of greater than 50% intracoronary stenotic lesions detected by MSCT was 15% and the metabolic syndrome was correlated with intracoronary stenosis detected by MSCT in Japanese SDB/OSA subjects.

TRIAL REGISTRATION

UMIN 000002997https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000003633&language=E.

Obesity overview: epidemiology, health and financial impact, and guidelines for qualification for surgical therapy

The aim of this article is to describe the context in which this issue of Gastrointestinal Endoscopy Clinics of North America is established. The authors review the current worldwide dimensions and trends of the obesity epidemic; associated mortality and comorbid diseases including diabetes, cancer, cardiovascular disease and obstructive sleep apnea; the financial impact of obesity; and current national and international guidelines for referral and qualification for surgical treatment of obesity.