Obstructive Sleep Apnea and Hypertension: Updates to a Critical Relationship

Molecular Processes Involved in the Shared Pathways between Cardiovascular Diseases and Diabetes

Cardiovascular diseases and diabetes mellitus are currently among the diseases with the highest morbidity and mortality. The pathogenesis and development of these diseases remain strongly connected, along with inflammation playing a major role. Therefore, the treatment possibilities showing a positive impact on both of these diseases could be especially beneficial for patients. SGLT-2 inhibitors and GLP-1 receptor agonists present this dual effect. Moreover, the hostile composition of the gut microbiota could influence the progression of these conditions. In this review, the authors present the latest knowledge on and innovations in diabetes mellitus and CVD-with the focus on the molecular mechanisms and the role of the microbiota.

AHI estimation of OSAHS patients based on snoring classification and fusion model

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a chronic and common sleep-breathing disease that could negatively influence lives of patients and cause serious concomitant diseases. Polysomnography(PSG) is the gold standard for diagnosing OSAHS, but it is expensive and requires overnight hospitalization. Snoring is a typical symptom of OSAHS. This study proposes an effective OSAHS screening method based on snoring sound analysis. Snores were labeled as OSAHS related snoring sounds and simple snoring sounds according to real-time PSG records. Three models were used, including acoustic features combined with XGBoost, Mel-spectrum combined with convolution neural network (CNN), and Mel-spectrum combined with residual neural network (ResNet). Further, the three models were fused by soft voting to detect these two types of snoring sounds. The subject's apnea-hypopnea index (AHI) was estimated according to these recognized snoring sounds. The accuracy and recall of the proposed fusion model achieved 83.44% and 85.27% respectively, and the predicted AHI has a Pearson correlation coefficient of 0.913 (R2 = 0.834, p < 0.001) with PSG. The results demonstrate the validity of predicting AHI based on analysis of snoring sound and show great potential for monitoring OSAHS at home.

Relationship between nocturia and hypertension: findings from the NHANES 2005-2016

Objectives

The objective of this study was to explore the association between nocturia and hypertension in a large, nationally representative adult sample.

Methods

We used data from 2005 to 2016 National Health and Nutritional Examination Surveys (NHANES). A total of 29,505 participants aged 20 years old or older were included. A participant was considered to have nocturia if he or she had two or more voiding episodes at night. Multivariable logistic regression models were used to explore the association between nocturia and hypertension.

Results

Participants with nocturia were associated with a higher risk of hypertension (OR, 1.36; 95% CI, 1.28-1.45). Interaction tests revealed no significant effect of sex, age, race, or body mass index on the association of nocturia with hypertension. As the severity of nocturia increases, the risk of hypertension increases (P for trend <0.0001). In addition, nocturia was also related to different grades of hypertension (II vs. I: OR, 1.34, 95% CI, 1.16-1.55; III vs. I: OR, 1.67, 95% CI, 1.32-2.13).

Conclusion

In this cross-sectional study, our results suggest that nocturia is associated with an increased risk for hypertension.

A Narrative Review of the Association of Obstructive Sleep Apnea with Hypertension: How to Treat Both When They Coexist?

Hypertension (HT) is a worldwide public health issue and an essential risk factor for cardiovascular and cerebrovascular diseases. Obstructive sleep apnea (OSA) is a condition characterized by recurrent episodes of apnea and hypopnea as a consequence of partial or complete obstruction of the upper airways due to anatomic and/or functional disturbances. There is mounting evidence of a relationship between OSA and HT. In patients with OSA, HT is predominantly nocturnal and characterized by high diastolic blood pressure and usually by a nondipping pattern. Optimizing the blood pressure control is recommended in the current guidelines as the first treatment option in hypertensive patients with OSA. Continuous positive airway pressure (CPAP) therapy may reduce blood pressure, albeit only slightly as a stand-alone treatment. CPAP, as an add-on treatment to antihypertensive medication, appears to be an efficient treatment modality when both conditions coexist. This narrative review aims to summarize the current perspectives on the association of OSA with HT and the treatment options available for adults with OSA-related HT.

10-Year Risk for Cardiovascular Disease Associated with COMISA (Co-Morbid Insomnia and Sleep Apnea) in Hypertensive Subjects

Due to the few studies available, this study aimed to investigate the 10-year risk for cardiovascular disease (CVD) associated with COMISA (co-morbid insomnia and sleep apnea) in hypertensive subjects. Clinical data of 1009 hypertensive subjects extracted from the Sleep Laboratory database were analyzed. Framingham Risk Score ≥ 10% was used as a cut-off to identify hypertensive subjects with high 10-year risk for CVD. The association between 10-year risk for CVD and COMISA was investigated using logistic regression analyses. 65.3% of hypertensive subjects from our sample presented a high 10-year risk for CVD. After controlling for major confounding factors, multivariate logistic regression analyses demonstrated that unlike its components present separately, COMISA was significantly associated with high 10-year risk for CVD in hypertensive subjects (OR 1.88, 95% CI 1.01-3.51). In this study, we have demonstrated that the negative synergy between obstructive sleep apnea syndrome and insomnia disorder seems to play a central role in the 10-year risk for CVD in hypertensive subjects, which seems to indicate that the establishment of a systematic research and an adapted treatment of COMISA could open new perspectives to promote a better cardiovascular outcome in this specific subgroup of patients.

[Obstructive sleep apnea syndrome and cardiovascular risk factors in the antihypertensive therapy "escape" phenomenon]

AIM

To assess the role of obstructive sleep apnea and other cardiovascular (CV) risk factors in the development of the antihypertensive therapy (AHT) efficacy "escape" phenomenon in patients with arterial hypertension (AH).

MATERIALS AND METHODS

The data of 75 patients with AH stage I-II, grades 1-3 were proceeded. All patients included in the study underwent night respiratory monitoring. After AHT prescription, blood pressure (BP) was monitored by three measurement methods (office, daily monitoring and self-control of blood pressure) - initially, in 1, 3 and 6 months after the inclusion - in order to confirm the initial therapy efficacy and to identify or exclude the "escape" phenomenon.

RESULTS

In 36.0% of patients, the "escape" phenomenon was diagnosed in 1 or 3 months of observation. When comparing the group with the "escape" phenomenon, an initially higher level of systolic BP was revealed according to office measurements, 24-hour monitoring and self-control BP monitoring (134.0±4.7 mmHg vs 126.0±8.5 mmHg; 129.0±2.3 mmHg vs 121.0±7.7 mmHg; 131.0±8.2 mmHg vs 121.5±6.2 mmHg resp.; р<0,05). There were no differences in sleep apnea and CV risk factors between the groups. However in patients with a minimal SpO₂≤85% during sleep, there were a higher levels of office systolic BP both before the AHT prescription, and during its use (157.6±10.4 mmHg vs 152.4±8.1 mmHg resp., р<0,05; 132.0±6.8 vs 127.1±8.9 mmHg resp.; р<0,05), and mean 24-hour systolic BP (125.7±5.9 vs 121.6±8.2 mmHg resp.; р<0,05) - compared with patients with a minimum SpO₂>85%.

CONCLUSION

The higher BP level in patients with lover nocturnal hypoxemia does not allow us to exclude the delayed negative impact of obstructive sleep apnea, especially severe, on the BP profile in case of initially successful AH control.

Arterial bicarbonate is associated with hypoxic burden and uncontrolled hypertension in obstructive sleep apnea - The ESADA cohort

OBJECTIVE

Blood bicarbonate concentration plays an important role for obstructive sleep apnea (OSA) patients to maintain acid-base balance. We investigated the association between arterial standard bicarbonate ([HCO3^-]) and nocturnal hypoxia as well as comorbid hypertension in OSA.

METHODS

A cross-sectional analysis of 3329 patients in the European Sleep Apnea Database (ESADA) was performed. Arterial blood gas analysis and lung function test were performed in conjunction with polysomnographic sleep studies. The 4% oxygen desaturation index (ODI), mean and minimum oxygen saturation (SpO₂), and percentage of time with SpO₂ below 90% (T90%) were used to reflect nocturnal hypoxic burden. Arterial hypertension was defined as a physician diagnosis of hypertension with ongoing antihypertensive medication. Hypertensive patients with SBP/DBP below or above 140/90 mmHg were classified as controlled-, uncontrolled hypertension, respectively.

RESULTS

The [HCO3^-] level was normal in most patients (average 24.0 ± 2.5 mmol/L). ODI, T90% increased whereas mean and minimum SpO₂ decreased across [HCO3^-] tertiles (ANOVA, p = 0.030, <0.001, <0.001, and <0.001, respectively). [HCO3^-] was independently associated with ODI, mean SpO₂, minimum SpO₂, and T90% after adjusting for confounders (β value [95%CI]: 1.21 [0.88-1.54], -0.16 [-0.20 to -0.11], -0.51 [-0.64 to -0.37], 1.76 [1.48-2.04], respectively, all p < 0.001). 1 mmol/L elevation of [HCO3^-] was associated with a 4% increased odds of uncontrolled hypertension (OR: 1.04 [1.01-1.08], p = 0.013).

CONCLUSION

We first demonstrated an independent association between [HCO3^-] and nocturnal hypoxic burden as well as uncontrolled hypertension in OSA patients. Bicarbonate levels as an adjunctive measure provide insight into the pathophysiology of hypertension in OSA.

Gut microbiota in hypertensive patients with versus without obstructive sleep apnea

We investigated the alteration of gut microbiota and the associated metabolic risks in hypertensive patients with obstructive sleep apnea (OSA) comorbidity. Fecal and blood samples were collected from 52 hypertensive patients, who were divided into three groups: A (controls, apnea-hypopnea index[AHI] < 5, n = 15), B (mild OSA, 5 < AHI < 20, n = 17), and C (moderate-to-severe OSA, AHI > 20, n = 20). The composition of the gut microbiota was studied through 16s RNA sequencing of variable regions 3-4. Analysis of the results revealed that group C had a significant higher concentration of total cholesterol, low-density lipoprotein, and IL-1β compared with group A. The Shannon index showed that bacterial biodiversity was lower in OSA patients. At the phylum level, the ratio of Firmicutes to Bacteroidetes (F/B) was significantly higher in group C than in groups A and B. At the genus level, the relative abundance of short-chain fatty acids (SCFA)-producing bacteria (e.g., Bacteroides and Prevotella) was lower while the number of inflammation-related bacteria (e.g., Lactobacillus) was increased in patients with OSA. We found that the IL-1β level was negatively correlated with Bacteroidetes. The area under the receiver operating characteristic curve was .672 for F/B ratio in determining hypertensive patients with OSA. In patients with hypertension, OSA was associated with worse gut dysbiosis, as evidenced by decreased levels of short-chain fatty acids-producing bacteria and increased number of inflammation-related bacteria. The differences in gut microbiota discriminate hypertensive patients with OSA from those without and may result in an enhanced inflammatory response and increase the risk of metabolic diseases.

Environmental Benefits of Sleep Apnoea Detection in the Home Environment

Sleep Apnoea (SA) is a common chronic illness that affects nearly 1 billion people around the world, and the number of patients is rising. SA causes a wide range of psychological and physiological ailments that have detrimental effects on a patient’s wellbeing. The high prevalence and negative health effects make SA a public health problem. Whilst the current gold standard diagnostic procedure, polysomnography (PSG), is reliable, it is resource-expensive and can have a negative impact on sleep quality, as well as the environment. With this study, we focus on the environmental impact that arises from resource utilisation during SA detection, and we propose remote monitoring (RM) as a potential solution that can improve the resource efficiency and reduce travel. By reusing infrastructure technology, such as mobile communication, cloud computing, and artificial intelligence (AI), RM establishes SA detection and diagnosis support services in the home environment. However, there are considerable barriers to a widespread adoption of this technology. To gain a better understanding of the available technology and its associated strength, as well as weaknesses, we reviewed scientific papers that used various strategies for RM-based SA detection. Our review focused on 113 studies that were conducted between 2018 and 2022 and that were listed in Google Scholar. We found that just over 50% of the proposed RM systems incorporated real time signal processing and around 20% of the studies did not report on this important aspect. From an environmental perspective, this is a significant shortcoming, because 30% of the studies were based on measurement devices that must travel whenever the internal buffer is full. The environmental impact of that travel might constitute an additional need for changing from offline to online SA detection in the home environment.

Associations of the Cardiometabolic Index with the Risk of Cardiovascular Disease in Patients with Hypertension and Obstructive Sleep Apnea: Results of a Longitudinal Cohort Study

Purpose

We aimed to explore the relationship between the cardiometabolic index (CMI) and cardiovascular disease (CVD) and its subtypes (coronary artery disease and stroke) in patients with hypertension and obstructive sleep apnea (OSA).

Methods

We conducted a retrospective cohort study enrolling 2067 participants from the Urumqi Research on Sleep Apnea and Hypertension study. The CMI was calculated as triglyceride to high‐density lipoprotein cholesterol ratio × waist‐to‐height ratio. Participants were divided into three groups (T1, T2, and T3) according to the tertile of CMI. The Kaplan-Meier method helped to calculate the cumulative incidence of CVD in different groups. We assessed the association of CMI with the risk of CVD and CVD subtypes by estimating hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox models.

Results

During a median follow-up of 6.83 years (interquartile range: 5.92-8.00 years), 326 incident CVD were identified, including 121 incident stroke and 205 incident coronary heart disease (CHD). Overall, after adjusting for confounding variables, CMI was positively associated with the risk of new-onset CVD (per SD increment, adjusted HR: 1.31; 95% CI: 1.20, 1.43), new-onset CHD (per SD increment, adjusted HR: 1.33; 95% CI: 1.20, 1.48), and new-onset stroke (per SD increment, adjusted HR: 1.27; 95% CI: 1.10, 1.47). Similar results were obtained in various subgroup and sensitivity analyses. Adding CMI to the baseline risk model for CVD improved the C-index (P < 0.001), continuous net reclassification improvement (P < 0.001), and integrated discrimination index (P < 0.001). Similar results were observed for CHD and stroke.

Conclusion

There was a positive association between CMI levels and the risk of new-onset CVD in patients with hypertension and OSA. This finding suggests that CMI may help identify people at high risk of developing CVD.