Moderate to severe obstructive sleep apnea during REM sleep as a predictor of metabolic syndrome in a Korean population

REM sleep obstructive sleep apnoea

Obstructive sleep apnoea (OSA) can occur in both rapid eye movement (REM) and non-REM sleep or be limited to REM sleep, when the upper airway is most prone to collapse due to REM sleep atonia. Respiratory events are usually longer and more desaturating in REM than in NREM sleep. The prevalence of REM OSA is higher in women than in men and REM OSA usually occurs in the context of mild-moderate OSA based on the apnoea-hypopnoea index calculated for the entire sleep study. Studies have highlighted some detrimental consequences of REM OSA; for example, its frequent association with systemic hypertension and a degree of excessive daytime sleepiness similar to that found in nonsleep-stage-dependent OSA. Moreover, REM OSA could increase cardiometabolic risk. Continuous positive airway pressure (CPAP) treatment aimed at preventing REM OSA should be longer than the 4 h usually considered as good compliance, since REM sleep occurs mostly during the second half of the night. Unfortunately, patients with REM OSA show poor adherence to CPAP. Alternative non-CPAP treatments might be a good choice for REM OSA, but data are lacking. This review summarises the available data on REM OSA and critically examines the weaknesses and strengths of existing literature.

Association between Rapid Eye Movement Obstructive Sleep Apnea and Metabolic Syndrome in a Japanese Population

Objective Rapid eye movement (REM) obstructive sleep apnea (OSA) is characterized by apnea and hypopnea events due to airway collapse occurring predominantly or exclusively during REM sleep. OSA is a potential risk factor for metabolic dysfunction. However, the association between REM OSA and risk of adverse health outcomes remains unclear. The present study investigated the association between REM OSA and metabolic syndrome (MetS), including the MetS components of hypertension, dyslipidemia, and hyperglycemia, in the Japanese population. Methods In total, 836 Japanese patients with mild to moderate OSA were enrolled in this study. We compared the prevalence of MetS, including hypertension, dyslipidemia, and hyperglycemia, between REM OSA and non-REM OSA via univariate analyses of descriptive statistics and logistic regression analyses. Results The prevalence of hypertension was 68.3% in the REM OSA group and 56.6% in the non-REM OSA group (p<0.05). In addition, the prevalence of metabolic syndrome was significantly higher (37.0%) in the REM OSA group than in the non-REM-OSA group (25.2%). Logistic regression analyses showed that the prevalence of hypertension and Mets was significantly greater in the REM OSA group than in the non-REM-OSA group. Conclusion Our findings suggest that patients with REM OSA, regardless of age, sex, and body mass index, are at a higher risk of developing hypertension and MetS than patients with non-REM OSA.

Rapid eye movement predominant obstructive sleep apnoea: prognostic relevance and clinical approach

PURPOSE OF REVIEW

Rapid eye movement (REM) obstructive sleep apnoea (OSA) is a stage-specific OSA, in which obstructive events occur primarily during REM sleep. This review discusses REM-OSA definitions, its cardiometabolic correlates, associated comorbidities and treatment, and addresses diagnostic ambiguities and therapeutic pitfalls.

RECENT FINDINGS

Current evidence indicates that REM-OSA is prevalent among younger age groups and women and is independently associated with cardiometabolic complications, particularly hypertension, metabolic complications such as insulin resistance and metabolic syndrome. However, currently, there is no consensus on the accepted diagnostic criteria for REM-OSA. Available data suggest that adherence to positive airway pressure (PAP) therapy in patients with REM-OSA is suboptimal. Moreover, the currently accepted criteria for good adherence to PAP therapy of 4 h/night, 70% of the days may not be suitable for REM-OSA, as it will not cover most of the REM sleep periods. In addition, further research is needed to assess the impact of REM-OSA treatment on cardiometabolic outcomes.

SUMMARY

Patients with REM-OSA are at an increased risk of cardiometabolic complications. A high index of suspicion is needed to diagnose this disorder, and close follow-up is required to enhance adherence to therapy.

Chronic apnea during REM sleep increases arterial pressure and sympathetic modulation in rats

STUDY OBJECTIVES

Obstructive sleep apnea can induce hypertension. Apneas in REM may be particularly problematic: they are independently associated with hypertension. We examined the role of sleep stage and awakening on acute cardiovascular responses to apnea. In addition, we measured cardiovascular and sympathetic changes induced by chronic sleep apnea in REM sleep.

METHODS

We used rats with tracheal balloons and electroencephalogram and electromyogram electrodes to induce obstructive apnea during wakefulness and sleep. We measured the electrocardiogram and arterial pressure by telemetry and breathing effort with a thoracic balloon.

RESULTS

Apneas induced during wakefulness caused a pressor response, intense bradycardia, and breathing effort. On termination of apnea, arterial pressure, heart rate, and breathing effort returned to basal levels within 10 s. Responses to apnea were strongly blunted when apneas were made in sleep. Post-apnea changes were also blunted when rats did not awake from apnea. Chronic sleep apnea (15 days of apnea during REM sleep, 8 h/day, 13.8 ± 2 apneas/h, average duration 12 ± 0.7 s) reduced sleep time, increased awake arterial pressure from 111 ± 6 to 118 ± 5 mmHg (p < 0.05) and increased a marker for sympathetic activity. Chronic apnea failed to change spontaneous baroreceptor sensitivity.

CONCLUSION

Our results suggest that sleep blunts the diving-like response induced by apnea and that acute post-apnea changes depend on awakening. In addition, our data confirm that 2 weeks of apnea during REM causes sleep disruption and increases blood pressure and sympathetic activity.

The Relationship between the Metabolic Syndrome and the Risk of Obstructive Sleep Apnea Evaluated by STOP-Bang Questionnaire in Professional Drivers in Shahroud, Iran, in 2020: A Case-Control Study

Background

The present study was conducted to investigate the relationship between metabolic syndrome and the risk of respiratory and sleep disorders in professional drivers.

Methods

This case-control study was conducted on professional drivers in Shahroud, Iran. The snoring, tiredness during daytime, observed apnea, high blood pressure, body mass index, age, neck circumference, gender (STOP-Bang) questionnaire was first used to assess obstructive sleep apnea (OSA). Then, based on the questionnaire scores, the participants were divided into two groups: those with and those without OSA. The relationship between this disorder and metabolic syndrome was then studied. Data were analyzed using descriptive and analytical tests (P<0.05).

Results

Based on the STOP-Bang questionnaire, 214 drivers with a high risk of OSA and 214 drivers with low risk were recruited for the study. According to the Adult Treatment Panel III criteria, 204 drivers (47.7%) had metabolic syndrome. There was a significant relationship between driver's license class and the risk of OSA. Metabolic syndrome components including fasting blood sugar, triglycerides, and hypertension, but not high-density lipoprotein cholesterol, were able to predict OSA in the professional drivers.

Conclusion

Given the high prevalence of metabolic syndrome and OSA, especially in drivers of high risk who may spend long hours transporting good and operating passenger vehicles, screening and treating these disorders are crucial in this part of the population. The researchers recommend holding regular training sessions about these disorders for professional drivers.

Higher Apnea-Hypopnea Index (AHI) and Oxygen Desaturation Index (ODI) Were Independently Associated with Increased Risks of Hypertension in Patients with T2DM: A Cross-Sectional Study

Objective

The current study aimed to explore the relationship between OSAS and hypertension and whether polysomnography (PSG) indices were independently associated with hypertension in patients with type 2 diabetes (T2DM).

Methods

This study recruited 316 T2DM patients. Multivariable logistic regression analyses were performed to determine the independent association of apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) with hypertension with adjustment for potential confounders.

Results

Among 316 patients, 130 (41.1%) and 204 (64.6%) had hypertension and OSAS, respectively. T2DM patients with hypertension showed significantly increased levels of AHI ((median (interquartile range)): 17.2 (5.7–34.9) vs. 5.7 (2.1–17.3) events/hour, p < 0.001), nonrapid eye movement AHI (NREM-AHI) (17.6 (5.5–36.5) vs. 5.2 (2.2–16.6) events/hour, p < 0.001), ODI (48.4 (21.9–78.0) vs. 22.6 (10.8–48.1) events/hour, p < 0.001), and severities of OSAS and decreased levels of lowest SaO₂ ((mean ± standard deviation): 74.0 ± 10.4 vs. 77.3 ± 9.8, p = 0.004). Multivariable logistic regression analysis showed that higher levels of AHI, NREM-AHI, and ODI were significantly associated with increased risks of hypertension, and the adjusted odds ratios (ORs) with 95% CI were 1.026 (1.008–1.044, p = 0.004), 1.026 (1.009–1.044, p = 0.003), and 1.005 (1.001–1.010, p = 0.040), respectively. Compared with non-OSAS, severe OSAS was significantly associated with the risk of hypertension with the adjusted OR (95% CI) of 3.626 (1.609–8.172, p = 0.002), but associations of rapid eye movement AHI (REM-AHI) and lowest SaO₂ with hypertension were not statistically significant.

Conclusion

Increased AHI, NREM-AHI, ODI, and severities of OSAS were significantly associated with higher risks of hypertension in T2DM patients. Detection and treatment of OSAS are needed to prevent hypertension in T2DM patients.

Lifestyle Modification Practices and Drug Prescription Use in Elderly Americans with Metabolic Syndrome: A Nationwide Population-Based Study

AIM

To determine differences in lifestyle modification practices and use of prescription drugs in a representative sample of Mexican American (MA), non-Hispanic White (NHW), and non-Hispanic Black (NHB) elderly Americans with metabolic syndrome (MetS).

METHODS

Data from the United States National Health and Nutritional Examination Surveys were used in this study. Lifestyle modification practices include ongoing physical activity, weight control, and ongoing diet modifications. Prescription drugs include anti-diabetic, anti-obesity, lipid-lowering, insulin sensitizers, renin-angiotensin system (RAS) blockers, fibrates, and cilostazol. Race/ethnic-specific prevalence odds ratios from the multivariate logistic regression analyses were used to determine associations between selected independent variables and MetS control (defined as the use of lifestyle modification practices or prescription drugs), adjusting for covariates.

RESULTS

The rates of ongoing weight control (73.4% versus 68.1% in MA and 66.3% in NHW) and diet modification practices (78.1% versus 77.4% in MA and 66.7% in NHW) were higher among NHB, and rate of ongoing physical activity (61.8% versus 52.8% in NHW and 56.4% in NHB) was higher among MA participants compared to their other racial/ethnic elderly counterparts (P < 0.001). Lipid-lowering and insulin-sensitizing drugs were the most commonly used prescription drugs in the last 30 days. The prevalence of nonuse of lifestyle modification practices or prescription drugs for MetS management was 15.1%, 21.3%, and 12.7% in MA, NHW, and NHB participants, respectively. MA, NHB race/ethnicity, a higher level of education, and increased BMI were significantly associated with increased odds of MetS control. Lack of drug prescription insurance and increased age were associated with decreased odds of MetS control.

CONCLUSIONS

Given the clinical importance of MetS, improving knowledge-based health decisions relative to lifestyle modification practices is very important. Moreover, sources of low-cost medications that links elderly patients with drug prescription coverage programs may help to improve the management of MetS.