A clinical approach to obstructive sleep apnea as a risk factor for cardiovascular disease

Sleep in the Athlete

Sleep is important for not only general health but also for lowering injury risk and maintaining athletic performance. Sleep disorders are prevalent in athletes, and taking a sleep history, evaluating sleep quality, and addressing other related factors including mental health are essential in diagnosing and understanding sleep disorders. Other methods such as polysomnography, actigraphy, and sheet sensors can also be used. Treatment options for sleep disorders include sleep hygiene, cognitive behavioral therapy, medication, and addressing contributing factors. For athletes, sleep can also be affected by factors such as travel fatigue and jet lag, which should be taken into consideration.

Craniofacial morphology in Obstructive Sleep Apnea patients

Background

To evaluate the correlation between cephalometric skeletal parameters and Obstructive Sleep Apnea syndrome (OSAs) severity, in adult patients with OSAs.

Material and Methods

One hundred patients (94 males,6 females mean age 59,3) with diagnosis of OSAs were retrospectively enrolled. Each patient received Home Sleep Apnea Testing (HSAT) and latero-lateral radiograph. Eight cephalometric parameters (cranial deflection angle, saddle angle, articular angle, divergence angle, cranial base angle, skull base length, mandibular length, maxilla length) were analyzed and then related to Apnea/Hypopnea Index (AHI) and to the Oxygen Desaturation Index (ODI), recorded by HSAT. A Spearman's rho correlation test between cephalometric measurements and HSAT indices was performed. Statistical significance was set at p< 0.05.

Results

A negative statistically significant correlation was found between mandibular length (Condilion-Gnathion distance) and AHI (rho= -0,2022; p<0,05) and between maxilla length (Ans-Pns) and AHI (rho= -0,2984; p<0,01) and ODI (rho= -0,2443; p<0,05). A statistically significant correlation was also observed between the divergence angle (S-N^Go-Me) and AHI (rho=0,2263; p<0,05) and between cranial deflection angle (Fh^NBa) and AHI (rho=0,2212; p<0,05) and ODI (rho=0,1970; p<0,05).

Conclusions

The OSAs severity may be related to certain predisposing features in craniofacial morphology, such as maxillary and mandibular length, divergence and cranial deflection. Key words:OSAs, Home Sleep Apnea Testing, AHI, ODI, Cephalometry, Airway.

Major Adverse Cardiac and Cerebrovascular Events in Geriatric Patients with Obstructive Sleep Apnea: An Inpatient Sample Analysis

BACKGROUND

Obstructive sleep apnea (OSA) is associated with an increased risk of major cardiac and cerebrovascular events (MACCE). However, data on the burden and predictors of MACCE in geriatric patients with OSA (G-OSA) remain limited.

METHODS

Using the National Inpatient Sample from 2018, we identified G-OSA admissions (age ≥ 65 years) and divided them into non-MACCE vs. MACCE (all-cause mortality, stroke, acute myocardial infarction, and cardiac arrest). We compared the demographics and comorbidities in both cohorts and extracted the odds ratio (multivariate analysis) of MACCE and associated in-hospital mortality.

RESULTS

Out of 1,141,120 geriatric obstructive sleep apnea G-OSA admissions, 9.9% (113,295) had MACCE. Males, Asians, or the Pacific Islander/Native American race, and patients from the lowest income quartile revealed a higher MACCE rate. Significant clinical predictors of MACCE in elderly OSA patients on multivariable regression analysis in decreasing odds were pulmonary circulation disease (OR 1.47, 95% CI 1.31-1.66), coagulopathy (OR 1.43, 95% CI 1.35-1.50), peripheral vascular disease (OR 1.34, 95% CI 1.28-1.40), prior sudden cardiac arrest (OR 1.34, 95% CI 1.11-1.62), prior myocardial infarction (OR 1.27, 95% CI 1.22-1.33), fluid and electrolyte imbalances (OR 1.25, 95% CI 1.20-1.29), male sex (OR 1.22, 95% CI-1.18-1.26), hyperlipidemia (OR 1.20, 95% CI 1.16-1.24), low household income (OR 1.19, CI 1.13-1.26), renal failure (OR 1.15, 95% CI 1.12-1.19), diabetes (OR 1.14, 95% CI 1.10-1.17), metastatic cancer (OR 1.14, 95% CI 1.03-1.25), and prior stroke or TIA (OR 1.12, 95% CI 1.07-1.17) (All p value < 0.05).

CONCLUSIONS

This study emphasizes the significant association between obstructive sleep apnea (OSA) and major cardiac and cerebrovascular events (MACCE) in the geriatric population. Among the elderly OSA patients, a substantial 9.9% were found to have MACCE, with specific demographics like males, Asian or Pacific Islander/Native American individuals, and those from the lowest income quartile being particularly vulnerable. The study sheds light on several significant clinical predictors, with pulmonary circulation disease, coagulopathy, and peripheral vascular disease topping the list. The highlighted predictors provide valuable insights for clinicians, allowing for better risk stratification and targeted interventions in this vulnerable patient cohort. Further research is essential to validate these findings and inform how tailored therapeutic approaches for geriatric OSA patients can mitigate MACCE risk.

CLINICAL IMPLICATIONS

Elderly individuals with a high risk for MACCE should undergo routine OSA screening using tools like the sensitive STOP-BANG Questionnaire. Implementing CPAP treatment can enhance cardiovascular outcomes in these patients.

Insights into the Use of Point-of-Care Ultrasound for Diagnosing Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a sleeping disorder caused by complete or partial disturbance of breathing during the night. Existing screening methods include questionnaire-based evaluations which are time-consuming, vary in specificity, and are not globally adopted. Point-of-care ultrasound (PoCUS), on the other hand, is a painless, inexpensive, portable, and useful tool that has already been introduced for the evaluation of upper airways by anesthetists. PoCUS could also serve as a potential screening tool for the diagnosis of OSA by measuring different airway parameters, including retropalatal pharynx transverse diameter, tongue base thickness, distance between lingual arteries, lateral parapharyngeal wall thickness, palatine tonsil volume, and some non-airway parameters like carotid intima-media thickness, mesenteric fat thickness, and diaphragm characteristics. This study reviewed previously reported studies to highlight the importance of PoCUS as a potential screening tool for OSA.

Racial disparity in gestational diabetes mellitus and the association with sleep-disordered breathing and smoking cigarettes: a cross-sectional study

BACKGROUND

Gestational diabetes mellitus (GDM) prevalence has risen in the U.S. and worldwide over the past decade. Minority groups, especially Asian and Hispanic women, are often disproportionately affected by GDM. Identifying modifiable risk factors such as sleep-disordered breathing and smoking and their interaction with race/ethnicity could play a pivotal role in preventing GDM.

METHODS

Data from the 2017-2018 National Health and Nutrition Examination Surveys (NHANES) were used to run a survey-weighted multivariable logistic regression assessing the association between sleep-disordered breathing and smoking with GDM among women aged 15-60 (n = 1326). The interaction term of the two predictors and race/ethnicity was introduced to the model to assess the interaction effect. The analyses were adjusted for age, marital status, education level, and BMI.

RESULTS

Approximately 13% of the participants reported having GDM. The lowest prevalence was observed among Non-Hispanic Blacks (7.8%) and the highest was among Other (15.5%). Sleep-disordered breathing was significantly associated with GDM (OR = 1.69, 95% CI 1.05, 2.73). No statistically significant association was observed between smoking and GDM (OR = 1.03, 95% CI 0.47, 2.27), and neither was the association between race/ethnicity and GDM. Furthermore, none of the interaction effects were statistically significant.

CONCLUSION

Preventive strategies targeting GDM should focus on improving modifiable risk factors, such as sleep-disordered breathing. It is important to screen women with sleep-disordered breathing and monitor their blood sugar before becoming pregnant to prevent the development of GDM. Future studies are recommended to understand the lower prevalence of GDM among Black women and the higher prevalence among "Other" race group which mostly includes Asian women.

Endothelin-1 as a novel target for the prevention of metabolic dysfunction with intermittent hypoxia in male participants

We examined the effect of intermittent hypoxia (IH, a hallmark feature of sleep apnea) on adipose tissue lipolysis and the role of endothelin-1 (ET-1) in this response. We hypothesized that IH can increase ET-1 secretion and plasma free fatty acid (FFA) concentrations. We further hypothesized that inhibition of ET-1 receptor activation with bosentan could prevent any IH-mediated increase in FFA. To test this hypothesis, 16 healthy male participants (32 ± 5 yr, 26 ± 2 kg/m2) were exposed to 30 min of IH in the absence (control) and presence of bosentan (62.5 mg oral twice daily for 3 days prior). Arterial blood samples for ET-1, epinephrine, and FFA concentrations, as well as abdominal subcutaneous adipose tissue biopsies (to assess transcription of cellular receptors/proteins involved in lipolysis), were collected. Additional proof-of-concept studies were conducted in vitro using primary differentiated human white preadipocytes (HWPs). We show that IH increased circulating ET-1, epinephrine, and FFA (P < 0.05). Bosentan treatment reduced plasma epinephrine concentrations and blunted IH-mediated increases in FFA (P < 0.01). In adipose tissue, bosentan had no effect on cellular receptors and proteins involved in lipolysis (P > 0.05). ET-1 treatment did not directly induce lipolysis in differentiated HWP. In conclusion, IH increases plasma ET-1 and FFA concentrations. Inhibition of ET-1 receptors with bosentan attenuates the FFA increase in response to IH. Based on a lack of a direct effect of ET-1 in HWP, we speculate the effect of bosentan on circulating FFA in vivo may be secondary to its ability to reduce sympathoadrenal tone.

In-hospital survival paradox in patients with sleep apnea-A nation-wide nested case-control study

BACKGROUND

Sleep apnea (SA) is a prevalent disorder characterized by recurrent events of nocturnal apnea originating from obstructive and/or central mechanisms. SA disrupts normal sleep and can lead to a series of complications when left untreated. SA results in intermittent hypoxia which has an impact on the cardio- and cerebrovascular system. Hospitalized patients with SA typically have a greater burden of comorbidity, a longer length of hospital stay, but may show an improvement of in-hospital mortality compared to patients without diagnosed SA. The reason for this survival benefit is controversial and we aimed to clarify this protective effect in the light of predictive factors including SA-associated comorbidities using a nation-wide hospitalization database.

METHODS AND FINDINGS

Data were extracted from a nation-wide hospitalization database provided by the Swiss Federal Office for Statistics. Hospitalized patients with a SA co-diagnosis were extracted from the database together with a 1:1-matched control population without SA. Overall, 212'581 patients with SA were hospitalized in Switzerland between 2002 and 2018. Compared to the controls, SA cases had a longer median length of hospital stay (7 days; 95% CI: 3 to 15 vs. 4 days; 95% CI: 2 to 10) (p < 0.001) and a higher median number of comorbidities (8 comorbidities; IQR: 5 to 11 vs. 3 comorbidities; IQR: 1 to 6) (p < 0.001). The risk of in-hospital mortality was lower in the SA cases compared to the controls (OR: 0.73; 95% CI: 0.7 to 0.76; p < 0.001). SA was associated with a survival benefit in hospitalizations related to 28 of 47 conditions with the highest rate of in-hospital death. Sixty-three comorbidities were significantly over-represented in SA cases among which obesity, hypertension and anatomic nasal deviations were associated with a significant decrease of in-hospital mortality.

CONCLUSIONS

Compared to matched controls, SA was associated with significant and relevant inpatient survival benefit in a number of most deadly conditions. Within SA-patients, associated comorbidities mostly correlated with a poorer prognosis, whereas obesity and hypertension were associated with an improved in-hospital mortality.

Stratifying the Risk of Cardiovascular Disease in Obstructive Sleep Apnea Using Machine Learning

OBJECTIVES/HYPOTHESIS

Obstructive sleep apnea (OSA) is associated with higher risk of morbidity and mortality related to cardiovascular disease (CVD). Due to overlapping clinical risk factors, identifying high-risk patients with OSA who are likely to develop CVD remains challenging. We aimed to identify baseline clinical factors associated with the future development of CVD in patients with OSA.

STUDY DESIGN

Retrospective analysis of prospectively collected data.

METHODS

We performed a retrospective analysis of 967 adults aged 45 to 84 years and enrolled in the Multi-Ethnic Study of Atherosclerosis. Six machine learning models were created using baseline clinical factors initially identified by stepwise variable selection. The performance of these models for the prediction of additional risk of CVD in OSA was calculated. Additionally, these models were evaluated for interpretability using locally interpretable model-agnostic explanations.

RESULTS

Of the 967 adults without baseline OSA or CVD, 116 were diagnosed with OSA and CVD and 851 with OSA alone 10 years after enrollment. The best performing models included random forest (sensitivity 84%, specificity 99%, balanced accuracy 91%) and bootstrap aggregation (sensitivity 84%, specificity 100%, balanced accuracy 92%). The strongest predictors of OSA and CVD versus OSA alone were fasting glucose >91 mg/dL, diastolic pressure >73 mm Hg, and age >59 years.

CONCLUSION

In the selected study population of adults without OSA or CVD at baseline, the strongest predictors of CVD in patients with OSA include fasting glucose, diastolic pressure, and age. These results may shape a strategy for cardiovascular risk stratification in patients with OSA and early intervention to mitigate CVD-related morbidity.

LEVEL OF EVIDENCE

3 Laryngoscope, 132:234-241, 2022.

OSA patients not treated with PAP - Evolution over 5 years according to the Baveno classification and cardiovascular outcomes

INTRODUCTION

The evolution of patients with obstructive sleep apnea (OSA) non-eligible for PAP-therapy at diagnosis is unknown. Currently, the severity of OSA is based on the apnea-hypopnea index (AHI), but its prognostic relevance has raised concerns. The Baveno classification may allow a better stratification of severity and therapeutic guidance in OSA.

METHODS

Patients with AHI≥5/h in 2015, classified into Baveno groups A and B and non-eligible for PAP therapy at diagnosis and over 5 years, were analyzed. Patients were reclassified into Baveno groups (A-D) and changes in groups over 5 years were explored. Patients in Baveno groups C and D, who developed major cardiovascular comorbidities (CVC) or end-organ damage (EOD group), were compared with patients in Baveno groups A and B (non-EOD group). To identify predictors of the development of major CVC or EOD, a logistic regression analysis was performed.

RESULTS

There were 76 patients, 58% male, mean age 51.9 ± 10.1 years, mean body mass index (BMI) of 30.3 ± 5.0 kg/m2 and median AHI of 8.9 (5.9-12.0) events/h. At diagnosis, 46% and 54% of patients were classified into Baveno group A and group B, respectively. In total, 21% of patients developed major CVC or EOD (Baveno group C or D); higher age (p = 0.011) and BMI (p = 0.004) and a higher percentage of central apneas (p = 0.012) at diagnosis significantly predicted it, while sex, sleepiness, insomnia, AHI, ODI and T90 were not.

CONCLUSIONS

A significant percentage of patients non-eligible for PAP-therapy at diagnosis of OSA developed CVC or EOD; higher age and BMI and a higher percentage of central apneas were significant predictors.

Diagnostic accuracy and suitability of instruments that screen for obstructive sleep apnoea, insomnia and sleep quality in cardiac patients: a meta-analysis

BACKGROUND

A number of clinical guidelines recommend that all cardiac rehabilitation patients should be screened for potential sleep disorders with a validated screening instrument. There is currently no consensus on what specific tools should be used.

OBJECTIVE

To identify tools that are practical to use in the clinical environment and have high diagnostic accuracy.

METHODS

We systematically searched online databases to identify patient reported outcome instruments that have been used in published research studies to assess the likelihood of obstructive sleep apnoea (OSA) in cardiac patients. In studies that provided diagnostic data, these data were extracted and verified via an evidence-based diagnostic calculator. Where sufficient numbers of studies were available, a meta-analysis was conducted to determine pooled estimates of specificity, sensitivity and diagnostic odds ratios. Selected papers were qualitatively assessed using the Standards for Reporting Diagnostic accuracy studies (STARD).

RESULTS

Of the 21 instruments identified, six detected likelihood of OSA, two assessed daytime sleepiness, five assessed insomnia and eight examined sleep quality. A meta-analysis of 14 studies that assessed diagnostic accuracy of moderate OSA, revealed moderate sensitivity for the Berlin Questionnaire, Sens = 0.49 (95% CI 0.45-0.52) and good sensitivity for the Stop-BANG, Sens = 0.93 (95% CI 0.87-0.96) but poor specificity at standard cut-off criteria.

CONCLUSION

There are promising practical tools available to screen patients with OSA and other sleep disorders in cardiac rehabilitation settings, but specificity could be improved. Additional assessment of sleep quality may enhance prognostic ability with both OSA and insomnia screening.

Health Preference Measures in Patients with Obstructive Sleep Apnea Syndrome Undergoing Continuous Positive Airway Pressure Therapy: Data from a Randomized Trial

BACKGROUND

In patients with obstructive sleep apnea syndrome (OSAS), the preference-based, health-related quality of life in terms of utility has not been extensively studied.

OBJECTIVE

To address this point, we compared the performance of different instruments assessing utility in patients with OSAS undergoing continuous positive airway pressure (CPAP) therapy.

MATERIALS AND METHODS

Data of 208 patients with OSAS (28 women, mean ± SE age 54.4 ± 0.7 years, apnea-hypopnea index (AHI) 51.9 ± 1.8/h, Epworth sleepiness score 13.4 ± 0.2) participating in a randomized trial of different CPAP modalities over 2 years were analyzed. Evaluations included sleep studies, Epworth sleepiness scale, and several utility instruments that measure subjective health preference on a scale ranging from 1 (most preferred and perfect health) to 0 (least preferred and very poor health).

RESULTS

After 2 years of CPAP therapy, the mean ± SE AHI was 6.7 ± 1.5/h and Epworth score 7.9 ± 0.4, both p < 0.001 versus baseline. Baseline utilities and changes (95% confidence interval) after 2 years of CPAP therapy were EuroQol 5-dimensions 0.79 ± 0.01, 0.02 (0.00-0.05, p = 0.064); short-form 6-dimension medical outcome questionnaire 0.72 ± 0.01, 0.06 (0.04-0.08, p < 0.001); Euro-thermometer visual analog scale 0.70 ± 0.01, 0.09 (0.07-0.12, p < 0.001); time trade-off 0.82 ± 0.01, 0.03 (0.01-0.06, p = 0.002); and standard gamble 0.82 ± 0.01, -0.01 (-0.03 to 0.02, p = 0.712).

CONCLUSION

The short-form 6-dimensions questionnaire, the Euro-thermometer, and the time trade-off instruments reflected the major clinical improvements in OSAS, while the EuroQoL 5-dimensions and standard gamble tests were not sensitive to CPAP effects. These results indicate that the evaluation of utility of a treatment for OSAS depends critically on the instrument used, which is important from an individual and societal perspective.

Increased risk of major depressive disorder in sleep apnea patients in Taiwan

The association between sleep apnea (SA) and depression had been reported in a few previous studies. However, whether SA increases the risk of major depressive disorder (MDD) has not been studied comprehensively in a large-scale study. We performed this population-based cohort study to assess the association between SA and MDD. We identified adult patients having SA from the Taiwan National Health Insurance Research Database and excluded those having MDD before SA diagnosis. Thirty control subjects were randomly selected to match to each SA patient by age and sex. Totally, 10,259 SA patients were matched to 102,590 control subjects. The incidence rate and cumulative incidence of MDD were significantly higher in SA patients than in the control subjects (both p < 0.0001). Multivariable Cox regression analysis showed that SA remained an independent risk factor for incident MDD after adjusting for age, sex, residency, income level, and comorbidities (hazard ratio = 2.9 [95% CI 2.8–3.1], p < 0.0001). In summary, SA patients have an increased risk to develop MDD. Physicians caring for SA patients must pay attention to their psychosocial health status.

Therapeutic value of the metabolomic active neurotransmitter isorhynchophylline in the treatment of spontaneously hypertensive rats by regulating neurotransmitters

Hypertension is one of the most reported cardiovascular and cerebrovascular diseases with significantly high morbidity and mortality rates. This condition threatens the very existence of human beings. Numerous studies conducted earlier revealed the good therapeutic effect of isorhynchophylline on hypertension since the former regulates the metabolic disorders in neurotransmitters. However, the mechanism behind this action is yet to be deciphered. The current study followed the targeted metabolomics method to investigate the changes in the neurotransmitter level in the hippocampus of spontaneously hypertensive rats (SHRs) after the rats were treated with isorhynchophylline. The authors predicted the metabolic pathways involved in extensively modified neurotransmitters. Further, the expressions of metabolism-key enzymes in mRNA and protein levels were also determined. When treated with isorhynchophylline, it induced notably varying metabolomic profiles of the hippocampus in SHRs. Isorhynchophylline perturbed a total of seven extensively modified neurotransmitters as well as the primarily related pathways such as tyrosine and glutamate metabolism. An increase in the key metabolic enzymes such as DDC, MAO, COMT, TH, and DβH was observed in the SHR group, whereas their levels decreased after treatment with isorhynchophylline. The expression of GAD67 established cross-current validity. So, isorhynchophylline has been proved to have potential therapeutic value to treat hypertension via tyrosine and glutamate metabolism in the hippocampus. Further, the current study also opened new ventures to further investigate the working mechanism of isorhynchophylline in hypertension.

Screening for Obstructive Sleep Apnea in an Atrial Fibrillation Population: What's the Best Test?

Background

Among individuals with nonvalvular atrial fibrillation (AF), the prevalence of obstructive sleep apnea (OSA) can be as high as 85%. Continuous positive airway pressure treatment for moderate or severe OSA might improve AF outcomes and quality of life, so early identification of OSA might be of value. However, screening questionnaires for OSA are suboptimal because they are weighted toward tiredness and loud snoring, which might be absent in AF patients. NoSAS (Neck, Obesity, Snoring, Age, Sex) is a new OSA questionnaire that excludes these parameters. Acoustic pharyngometry (AP) is a potential novel screening technique that measures pharyngeal cross-sectional area, which is reduced in patients with OSA.

Methods

We prospectively compared the accuracy of the NoSAS, the STOP-BANG questionnaire (Snoring, Tiredness, Observed apnea, blood Pressure, Body mass index, Age, Neck circumference and Gender), and AP with home sleep apnea testing (HSAT) in consecutive patients with nonvalvular AF.

Results

Of 188 participants, 86% had OSA and 49% had moderate or severe OSA. Mean Epworth Sleepiness Scale scores were low; 5.9 (SD, 3.9), indicating that most participants were not sleepy. Receiver operating characteristic curves for comparisons of screening tests with HSAT showed suboptimal accuracy. For moderate plus severe and severe only groups respectively, the area under the curve was 0.50 (95% confidence interval [CI], 0.42-0.58) and 0.42 (95% CI, 0.34-0.52) for AP, 0.65 (95% CI, 0.58-0.73) and 0.63 (95% CI, 0.52-0.74) for the STOP-BANG questionnaire, and 0.68 (95% CI, 0.60-0.75) and 0.69 (95% CI, 0.59-0.80) for the NoSAS.

Conclusions

AP and NoSAS are not sufficiently accurate for screening AF patients for OSA. Because of the high rates of OSA in this cohort, the potential benefits of OSA treatment, and the suboptimal accuracy of current screening questionnaires, cardiologists should consider HSAT for AF patients.

Cardiovascular Outcomes Post Percutaneous Coronary Intervention in Patients with Obstructive Sleep Apnea and Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is a major risk factor for the occurrence of cardiovascular diseases. Similar to T2DM, obstructive sleep apnea (OSA) is also known to be a risk factor for cardiovascular diseases. In this analysis, we aimed to systematically compare the post-interventional cardiovascular outcomes observed in patients with T2DM with versus without OSA.

METHODS

Electronic databases were searched for relevant publications comparing the cardiovascular outcomes following percutaneous coronary intervention (PCI) in patients with T2DM with OSA. Cardiovascular outcomes were considered as the relevant endpoints. The RevMan software 5.3 was used to carry out the statistical analysis. Odds ratios (OR) with 95% confidence intervals (CI) were used to represent the results following data assessment.

RESULTS

A total of 1168 participants with T2DM were included in this analysis, of whom 614 had co-existing OSA. The time period of patients' enrollment varied from year 2002 to 2017. Our current analysis showed that major adverse cardiac events (MACEs) (OR 2.28, 95% CI 1.24-4.18; P = 0.008) and all-cause mortality (OR 1.95, 95% CI 1.08-3.54; P = 0.03) were significantly higher in the OSA subgroup. However, major adverse cerebrovascular and cardiovascular (MACCEs) (OR 1.38, 95% CI 0.97-1.98; P = 0.07) and cardiac death (OR 1.79, 95% CI 0.77-4.16; P = 0.18) were not significantly different post PCI. In addition, hospitalization for heart failure (OR 1.99, 95% CI 0.43-9.25; P = 0.38), re-infarction (OR 1.52, 95% CI 0.85-2.70; P = 0.16), stroke (OR 1.81, 95% CI 0.81-4.08; P = 0.15), target vessel revascularization (TVR) (OR 1.54, 95% CI 0.98-2.42; P = 0.06), and target lesion revascularization (TLR) (OR 1.32, 95% CI 0.80-2.18; P = 0.28) were also not significantly different post PCI in the patients with T2DM with versus without OSA.

CONCLUSION

OSA was associated with a significant increase in all-cause mortality and MACEs post PCI in these patients with T2DM. Therefore, special care and continuous follow-up might be required for patients with T2DM with associated OSA after PCI. However, as a result of the limited number of participants, further larger studies would be required to confirm these hypotheses.

Construct validity and reproducibility of the six-minute step test in subjects with obstructive sleep apnea treated with continuous positive airway pressure

OBJECTIVE

To evaluate the construct validity and reproducibility of the six-minute step test (6MST) in individuals with obstructive sleep apnea (OSA) treated with continuous positive airway pressure (CPAP).

METHODS

We evaluated 48 volunteers diagnosed with OSA and treated with CPAP for at least two months. The volunteers underwent the six-minute walk test (6MWT) and the 6MST, in random order and on different days, with an interval of, at most, seven days between the two tests.

RESULTS

A moderate positive correlation was found between the distance walked on the 6MWT and the number of steps climbed on the 6MST (r = 0.520; p < 0.001). There was no significant difference between the two 6MSTs in terms of the number of steps climbed (121.7 ± 27.1 vs. 123.6 ± 26.7). Reproducibility for performance on the 6MST and for cardiovascular variables was considered excellent (intraclass correlation coefficient > 0.8). Regarding cardiovascular responses, the 6MST produced higher values than did the 6MWT for HR at six minutes, percent predicted maximum HR, and leg fatigue at six minutes, as well as for systolic blood pressure at six minutes and at one minute of recovery.

CONCLUSIONS

The 6MST is valid and reproducible, producing greater cardiovascular stress than does the 6MWT. However, the 6MST is also characterized as a submaximal test for the assessment of exercise tolerance in individuals with OSA treated with CPAP.

Oropharyngeal rhabdomyoma: the cause of severe sleep apnoea?

This case report presents an elderly male patient who on diagnosis with a large oropharyngeal tumour had no specific symptomatology apart from severe obstructive sleep apnoea. Histopathology revealed the tumour to be an adult rhabdomyoma, a rare but benign tumour arising from striated muscle cells. The tumour obstructed most of the oropharyngeal space and almost occluded the patient's airway when lying in a supine position. The patient was deemed operable, and the tumour was excised in toto using a transoral robotic surgery system. On follow-up, the patient had a severe reduction of apnoeas/hypopnoeas and felt subjectively 'reborn'. This is to our knowledge the first case where an adult rhabdomyoma is removed using a robot-assisted approach, thus presenting a new and viable option when considering removal of benign tumours of the pharynx leading to a very minor degree of morbidity for the patients.

Risk detection in patients with obstructive sleep apnea syndrome based on cardiovascular time series analysis

Obstructive sleep apnea represents the most common form of sleep-disordered breathing and has a high prevalence in patients with cardiovascular disease. Disturbed sleep is a potential risk factor for cardiovascular disorders such as arterial hypertension, cardiac ischemia, sudden cardiac death, and stroke. In this study we investigated polysomnographic records and analyzed the ECG, plethysmogram, respiration and SpO2 time series during wakefulness (WK), NREM, and REM sleep stages applying variability and coupling analyses methods. We enrolled 55 patients with obstructive sleep apnea syndrome (OSAS) and 29 healthy control subjects (CON: 45.9±14.9 years, 21 male) in this study. OSAS patients were subdivided into a low- and high-risk group (LR: 50.8±14.1 years, n=29, 21 male; HR: 57.2±13.4 years, n=26, 19 male) based on the Apnea-Hypopnea Index (AHI) (CON: 0-5 AHI, LR: 5-15 AHI, HR: >15 AHI). We could demonstrate the presence of an altered autonomic function in OSAS patients, differing from healthy controls. This altered autonomic function was mainly based on heart rate-, respiratory-, SpO2- and plethysmogram variability and their couplings. The discriminant analysis showed that the optimal set consisting of two autonomic indices revealed a high classification power (ACC=86.7%, AUC=90.3%, SENS=89.5% and SPEC=84.6%) when comparing low-risk and high-risk OSAS patients during WK. These results were slightly improved when analyzing REM sleep stages. Based on these results it seems to be possible to perform optimal risk stratification for OSAS patients based on autonomic indices. Based on our findings it is possible to differentiate between high-risk OSAS patient and low-risk OSAS patient at an early stage and in a promising manner allowing to set up therapy strategies for those patients in an early stage.

Repercussion of medium and long treatment period with continuous positive airways pressure therapy in heart rate variability of obstructive sleep apnea

Introduction

Obstructive sleep apnea (OSA) is a respiratory sleep disorder. Many of these patients also exhibit autonomic alterations which can be observed through heart rate variability (HRV). Currently, one of the treatments for apnea is continuous positive airway pressure (CPAP).

Objective

To observe OSA patients treated with CPAP exhibit HRV changes at medium and long treatment period.

Methods

This is an integrative literature review conducted in May of 2018. The databases used for this research were PubMed, Scopus, Scielo and Pedro, the keywords used were “heart rate variability”, “obstructive sleep apnea” and “CPAP”. In this review was included original, published, randomized and non-randomized articles, released in the English language, before and up to April 2018, which specified the effects of CPAP therapy in autonomic dysfunction through the analysis of the HRV of patients diagnosed with OSA after at least one month of therapy.

Results

The research of the literature produced 113 articles. After excluding duplicates and applying the inclusion and exclusion criteria, 8 articles were selected for this review.

Conclusion

It was concluded that CPAP therapy is related to change in heart rate variability in patients with obstructive sleep apnea.

The Clinical Value of N-Terminal Pro B-Type Natriuretic Peptide in Evaluating Obstructive Sleep Apnea in Patients With Coronary Artery Disease

STUDY OBJECTIVES

Natriuretic peptides have been identified as biomarkers of increased myocardial wall stress in the context of obstructive sleep apnea (OSA) in the general population. However, the relationship between N-terminal pro B-type natriuretic peptide (NT-proBNP) and OSA remains unclear in patients with coronary artery disease (CAD). Hence, we aimed to investigate the clinical value of NT-proBNP in evaluating OSA in a large population of patients with CAD.

METHODS

Consecutive patients with CAD were prospectively enrolled between February 2015 and March 2018. Portable respiratory monitoring was applied to facilitate the diagnosis of sleep apnea. Patients were as assigned to the non-OSA (when the respiratory events index [REI] or 3% oxygen desaturation index [ODI] < 15 events/h) and OSA (when the REI or 3% ODI ≥ 15 events/h) groups. Multivariate analyses were used to explore the independent association between NT-proBNP levels and OSA.

RESULTS

A total of 1,292 consecutive patients were included with a mean NT-proBNP value of 826.57 μg/L. Patients with high levels of NT-proBNP experienced increasing severity of OSA in those with CAD (P = .0004). Univariate analysis demonstrated that NT-proBNP was a risk factor for OSA (odds ratio [OR] 1.10, 95% confidence interval [CI] 1.03-1.18, P = .005). In addition, multivariate analysis revealed that NT-proBNP was independently associated with the presence of OSA (OR 1.11, 95% CI 1.02-1.20, P = .012) even after adjusting for other cofounding factors.

CONCLUSIONS

Elevated levels of NT-proBNP were independently associated with a higher likelihood of OSA in patients with CAD. Periodically screening for NT-proBNP levels may provide early identification of OSA.

The Effects of Eplerenone on the Circadian Blood Pressure Pattern and Left Ventricular Hypertrophy in Patients with Obstructive Sleep Apnea and Resistant Hypertension-A Randomized, Controlled Trial

The obstructive sleep apnea (OSA) is highly associated with various significant cardiovascular outcomes such as resistant hypertension (RAH). Despite this, as of now the relationship between high night-time blood pressure (BP) and left ventricular hypertrophy (LVH) in patients with OSA and RAH is not fully understood. The aim of this study was to assess the influence of the addition of eplerenone to a standard antihypertensive therapy on parameters of 24-h ambulatory blood pressure measurement (ABPM) as well as on the results of echocardiography and polysomnography in patients with OSA and RAH. The patients were randomly assigned to one of the two study groups: the treatment group, receiving 50 mg/d eplerenone orally for 6 months (n = 51) and the control group, remaining on their standard antihypertensive therapy (n = 51). After that period, a significant reduction in the night-time BP parameters in the treatment group including an increased night blood pressure fall from 4.6 to 8.9% was noted. Additionally, the number of non-dipper patients was reduced by 45.1%. The treatment group also revealed a decrease in left ventricular hypertrophy and in the apnea-hypopnea index (AHI) with a positive correlation being observed between these two parameters. This study is the first to report the improvement of the circadian BP profile and the improvement of the left ventricle geometry in patients with OSA and RAH following the addition of selective mineralocorticoid receptor antagonists to antihypertensive therapy.

The association between aortic knob width on chest x-ray and obstructive sleep apnoea syndrome in patients referred for sleep testing

OBJECTIVE

Obstructive sleep apnoea (OSA) has been linked with many forms of cardiovascular diseases. Aortic knob width (AKW) has increasingly been presented as a marker of diagnosis and prognosis of atherosclerotic coronary artery disease. We sought to determine whether AKW has an association with sleep apnoea syndrome in patients referred to sleep testing in order to provide baseline information for future studies on general population.

METHODS

A total of 363 patients were included in this retrospective study. The capacity of AKW indexed by patients' height in predicting the presence of severe OSA was analysed using receiver operating characteristics curve analysis. The association of OSA severity with AKW indexed by height was tested with two separate models of ANCOVA (analysis of variance).

RESULTS

Area under the curve for estimating severe OSA with AKW was 0.67 (95% CI, 0.60 to 0.73, P < 0.001). A cut-off value of 21.42 mm/m provided a sensitivity of 62.6% and a specificity of 70.7% for severe OSA. In both ANCOVA models, the association of OSA severity on AKW indexed by height was significant and the effect size was moderate (P < 0.001, partial eta squared: 0.09 and 0.05).

CONCLUSIONS

Aortic knob width indexed by height has a significant association with the severity of OSA; however, the association is significantly influenced by gender and age.

Pathologic and hemodynamic changes of common carotid artery in obstructive sleep apnea hypopnea syndrome in a porcine model

Background/aim

To prepare a porcine model of obstructive sleep apnea-hypopnea syndrome (OSAHS) and observe the pathological and hemodynamic changes in the common carotid artery.

Materials and methods

Twelve male miniature pigs were randomly divided into the model and control group (n = 6). Pigs in the model group were kept in an air-flow negative pressure chamber at 0.96 ± 0.01 kPa, and the air oxygen content, temperature, and humidity were kept at normal culture conditions in both groups. After pigs in the model group presented symptoms of OSAHS, changes in the hemodynamics and morphology of the carotid artery were analyzed using color Doppler, and light and electron microscopy.

Results

An animal model of OSAHS was successfully created. The internal diameter of the carotid artery of pigs in the model group was decreased, while the intima thickness, peak-systolic mean velocity, and resistance index were increased when compared to the control group (P < 0.05). The results of the light and electron microscopy revealed an incomplete elastic plate, increased media thickness, irregular morphology of the smooth muscle cells, increased collagen fiber bundles, partially disordered elastic fibers, and smooth muscle layers. The quantitative analysis showed significantly increased elastic fibers in the media of the carotid artery in the model group (P < 0.01).

Conclusion

Pathological changes in the tissue structure and hemodynamics in the negative pressure-induced pig OSAHS model were observed. We suggest that alterations in the upper airway pressure during OSAHS may lead to cardiovascular conditions through its pathological effects on the carotid artery.

Effect of mean apnea-hypopnea duration in patients with obstructive sleep apnea on clinical and polysomnography parameter

OBJECTIVE

Apnea-hypopnea index is the number of apnea-hypopnea events observed during polysomnography within an hour. Mean apnea-hypopnea duration is the mean duration of all apneas and hypopneas. In this study, we aimed to investigate the association of mean apnea-hypopnea duration in patients with obstructive sleep apnea with clinical and polysomnographic parameters.

METHODS

In our hospital, a total of 764 patients were diagnosed with OSA by polysomnography in 2017. Age, body mass index, and the current diseases were recorded. Sleep structures obtained from polysomnography readings, blood oxygen levels, apnea-hypopnea index, and mean average duration were recorded. Patients with mean average duration of 20 s or more were assigned to the long average duration group and those with less than 20 s were assigned to the short average duration group. Groups were compared in terms of clinical and polysomnographic parameters.

RESULTS

Snoring, witnessed apnea, morning tiredness, and hypertension were significantly higher in the long average duration group. There was statistically significantly more male patients and higher neck circumference in the MAD group. Total wake duration, percentage of sleep, stage 3, stage 1, and mean oxygen saturation percentage of the long average duration group were significantly reduced.

CONCLUSION

In present study, the patients with obstructive sleep apnea with long average duration were found to have more negative effects of sleep apnea than the patients with short average duration. We think that the use of mean apnea-hypopnea duration as an indicator with apnea-hypopnea index will be beneficial for the follow-up and treatment of the disease.

N-terminal pro-brain natriuretic peptide: a potential follow-up biomarker of mandibular advancement device efficacy on cardiac function in obstructive sleep apnea

Interrelationships between obstructive sleep apnea (OSA) and cardiovascular diseases are now recognized, but some underlying pathophysiological mechanisms remain controversial. Circulating cardiac biomarkers are diagnostic tools that can help understand them, in particular the N-terminal pro-brain natriuretic peptide (NT-proBNP), a marker of myocardial stretch, and a potential indicator of subclinical cardiac stress in OSA. Continuous positive airway pressure (CPAP), the first-line treatment of moderate to severe OSA, may be considered as uncomfortable, resulting in poor adherence, and reduced effectiveness. In this case, mandibular advancement devices (MAD) are an effective alternative therapy, more comfortable, and generally well accepted, with higher compliance. To date, few studies have compared the cardiovascular effects of CPAP and MAD. From recent literature reviews, it emerges that both therapies are effective in blood pressure reduction. However, the effects of MAD on other cardiovascular outcomes are conflicting, in particular as regards to its impact on circulating cardiac biomarkers. In a recent ancillary study from a randomized controlled trial, Recoquillon et al concluded that two months of MAD treatment had no effect on NT-proBNP plasma levels in patients with severe OSA. The present discussion analyses this result from a biological, statistical, and analytical standpoint, in light of results from other studies evaluating natriuretic peptides in MAD-treated OSA, with the aim to support further longitudinal studies designed with a high methodological quality.

Sleep Disorders

Sleep disorders are frequent and can have serious consequences on patients' health and quality of life. While some sleep disorders are more challenging to treat, most can be easily managed with adequate interventions. We review the main diagnostic features of 6 major sleep disorders (insomnia, circadian rhythm disorders, sleep-disordered breathing, hypersomnia/narcolepsy, parasomnias, and restless legs syndrome/periodic limb movement disorder) to aid medical practitioners in screening and treating sleep disorders as part of clinical practice.

When Office Blood Pressure Is Not Enough: The Case of Masked Hypertension

An increasing attention has been devoted in the last two decades to masked hypertension (MH), a condition characterized by the fact that classification of a normal blood pressure (BP) status by office measurements is not confirmed by home and/or ambulatory BP monitoring (ABPM). MH definition (i.e., normal office BP, but high out-of-office BP) should be restricted to untreated subjects (true MH) whereas masked uncontrolled hypertension (MUCH) reserved to treated patients previously classified as hypertensives, presenting normal office BP and high ABPM or home values. Both MH and MUCH are associated with metabolic alterations, comorbidities, and hypertension-mediated organ damage (HMOD). Furthermore, the risk of cardiovascular events related to these conditions has been shown to be close or greater than that of sustained hypertension. This review discusses available evidence about MH and MUCH by focusing on its prevalence, clinical correlates, association with HMOD, prognostic significance, and their therapeutic implications.

Distance to Specialist Medical Care and Diagnosis of Obstructive Sleep Apnea in Rural Saskatchewan

Obstructive sleep apnea (OSA) is the most common sleep-disordered breathing condition. Patients with OSA symptoms are often not diagnosed clinically, which is a concern, given the health and safety risks associated with unmanaged OSA. The availability of fewer practicing medical specialists combined with longer travel distances to access health care services results in barriers to diagnosis and treatment in rural communities. This study aimed to (1) determine whether the proportion of adults reporting OSA symptoms in the absence of a sleep apnea diagnosis in rural populations varied by travel distance to specialist medical care and (2) assess whether any distance-related patterns were attributable to differences in the frequency of diagnosis among adults who likely required this specialist medical care. We used a cross-sectional epidemiologic study design, augmented by analysis of follow-up survey data. Our study base included adults who completed a 2010 baseline questionnaire for the Saskatchewan Rural Health Study. Follow-up occurred until 2015. 6525 adults from 3731 households constituted our sample. Statistical models used log-binomial regression. Rural adults who reported the largest travel distances (≥250 km) to specialist medical care were 1.17 (95% CI: 1.07, 1.29) times more likely to report OSA symptoms in the absence of a sleep apnea diagnosis than those who reported the smallest (<100 km; referent) distances. However, the proportion of sleep apnea diagnoses was low and unaffected by reported travel distance among adults who likely required this specialist medical care. Our findings suggest factors other than travel distance may be contributing to the low sleep apnea diagnostic rate. This remains important as undiagnosed and untreated OSA has serious implications on the health of people and populations, but effective treatments are available. Health care access barriers to the diagnosis and treatment of OSA require evaluation to inform health care planning and delivery.

Quantitative analysis of carotid arterial calcification using airway CT in obstructive sleep apnea

OBJECTIVE

To evaluate the relationship between obstructive sleep apnea (OSA) severity and carotid arterial calcification by quantitative analysis using airway computed tomography (CT).

METHODS

This study included a total of 180 consecutive OSA patients aged 45-80years underwent polysomnography and airway CT between March 2014 and October 2016. The subjects were divided into three groups based on the results of the respiratory disturbance index (RDI): mild (RDI 5-14, n=29), moderate (RDI 15-29, n=50), and severe (RDI≥30, n=101). The extent of carotid arterial calcification on each airway CT scan was quantified according to the modified Agatston scoring method. Differences among the three groups in clinical characteristics including age, gender, body mass index (BMI), comorbid disease, blood pressure, total cholesterol, and carotid arterial calcification score (CarACS) were analyzed.

RESULTS

The severe OSA group showed significantly stronger predominance for male and smoker, higher prevalence of diabetes, and larger BMI than those of mild and moderate OSA groups. The mean CarACS was significantly different among the three groups (mild RDI: 4.3±13.4, moderate RDI: 7.4±28.8, severe RDI: 48.6±121.6, P=0.011). Univariate linear regression showed that RDI, age, hypertension, male sex and diabetes significantly influenced on the CarACS. In a multivariate linear regression model, the CarACS was related to age, male sex, and diabetes.

CONCLUSIONS

The patients with severe OSA showed larger CarACS and a higher prevalence of atherosclerotic risk factors. The CarACS was correlated with severity of OSA, which might be more dependent on the conventional risk factors of atherosclerosis.

Sleep study-guided multidisciplinary therapy (SGMT) for patients with acute coronary syndrome: Trial rationale and design

Obstructive sleep apnea (OSA) is an emerging risk marker for acute coronary syndrome (ACS). This randomized trial aims to determine the effects of sleep study-guided multidisciplinary therapy (SGMT) comprising overnight sleep study, continuous positive airway pressure, and behavioral therapy for OSA during the subacute phase of ACS. We hypothesize that SGMT will reduce (1) the plasma levels of N-terminal pro brain natriuretic peptide and suppression of tumorigenicity 2; (2) the estimated 10-year risk of cardiovascular mortality as measured by the European Systematic Coronary Risk Evaluation (SCORE) algorithm; and (3) the cardiovascular event rate during a 3-year follow-up, compared with standard therapy. In the SGMT trial, 180 patients presenting with ACS will be randomly assigned to SGMT (n = 90) and standard therapy (n = 90) groups. Both groups will receive guideline-mandated treatment for ACS. Those assigned to SGMT will additionally undergo a sleep study and, if OSA is diagnosed, attend a multidisciplinary OSA clinic where they will receive personalized treatment including continuous positive airway pressure and behavioral/lifestyle counseling. The primary endpoint is the plasma N-terminal pro brain natriuretic peptide concentration at 7-month follow-up. This report presents the baseline characteristics of 117 patients (SGMT group: n =54; standard therapy group: n =63) who had been enrolled into the study as of August 31, 2017. The results of this trial will help us to understand whether active OSA diagnosis and treatment will improve the physiologic and clinical cardiovascular outcomes of this group of patients.

Endothelin-1 and ET receptors impair left ventricular function by mediated coronary arteries dysfunction in chronic intermittent hypoxia rats

Obstructive sleep apnea (OSA) results in cardiac dysfunction and vascular endothelium injury. Chronic intermittent hypoxia (CIH), the main characteristic of OSAS, is considered to be mainly responsible for cardiovascular system impairment. This study is aimed to evaluate the role of endothelin‐1(ET‐1) system in coronary injury and cardiac dysfunction in CIH rats. In our study, Sprague–Dawley rats were exposed to CIH (FiO₂ 9% for 1.5 min, repeated every 3 min for 8 h/d, 7 days/week for 3 weeks). After 3 weeks, the left ventricular developed pressure (LVDP) and coronary resistance (CR) were measured with the langendorff mode in isolated hearts. Meanwhile, expressions of ET‐1 and ET receptors were detected by immunohistochemical and western blot, histological changes were also observed to determine effects of CIH on coronary endothelial cells. Results suggested that decreased LVDP level combined with augmented coronary resistance was exist in CIH rats. CIH could induce endothelial injury and endothelium‐dependent vasodilatation dysfunction in the coronary arteries. Furthermore, ET‐1 and ET_A receptor expressions in coronary vessels were increased after CIH exposure, whereas ET_B receptors expression was decreased. Coronary contractile response to ET‐1 in both normoxia and CIH rats was inhibited by ET_A receptor antagonist BQ123. However, ET_B receptor antagonist BQ788 enhanced ET‐1‐induced contractile in normoxia group, but had no significant effects on CIH group. These results indicate that CIH‐induced cardiac dysfunction may be associated with coronary injury. ET‐1 plays an important role in coronary pathogenesis of CIH through ET_A receptor by mediating a potent vasoconstrictor response. Moreover, decreased ET_B receptor expression that leads to endothelium‐dependent vasodilatation decline, might be also participated in coronary and cardiac dysfunction.

Peripapillary Choroidal Thickness and Retinal Nerve Fiber Layer in Untreated Patients with Obstructive Sleep Apnea-Hypopnea Syndrome: A Case-Control Study

PURPOSE

To evaluate peripapillary choroidal thickness (PPCT), central macular choroidal thickness (CMCT), and retinal nerve fiber layer (RNFL) thickness in untreated patients with obstructive sleep apnea-hypopnea syndrome (OSAHS).

METHODS

This prospective, randomized, and comparative study was conducted in a university ophthalmology clinic. 106 eyes of 106 patients with OSAHS and 44 eyes of 44 healthy individuals were evaluated in this study. Only right eyes were evaluated. The patients with OSAHS were divided into three groups as mild (group 1), moderate (group 2), and severe (group 3) according to apnea-hypopnea index. The PPCT, CMCT, and RNFL measurements were performed by using spectral domain optical coherence tomography with enhanced depth imaging technique. The main parameters assessed were PPCT-Temporal, PPCT-Superior, PPCT-Nasal, PPCT-Inferior quadrants, CMCT, and RNFL thicknesses.

RESULTS

The PPCT of all quadrants was significantly thicker in the control group compared with the moderate and severe subgroups of OSAHS (p < 0.05). The PPCT-Superior and PPCT-Temporal were significantly thinner in the mild subgroup compared with the control group (p = 0.003 and p = 0.028, respectively). There was no difference between the control and mild groups regarding the RNFL thicknesses except nasal RNFL and inferotemporal RNFL which are thinner in the mild group. The RNFL thicknesses of all quadrants were significantly thicker in the control group compared with moderate and severe subgroups (p < 0.05). The CMCT was significantly thicker in the control group compared with all subgroups of OSAHS (p < 0.05).

CONCLUSIONS

In OSAHS patients, PPCT, CMCT, and RNFL were significantly thinner compared with the control group. These results may explain why OSAHS patients are prone to normotensive glaucoma.

Patients with symptoms and characteristics consistent with obstructive sleep apnea are at a higher risk for acute and subacute stent thrombosis after percutaneous coronary stent implantation: a single-center case-control study

Background

To determine if obstructive sleep apnea (OSA) is a risk factor for early stent thrombosis (EST; within 30 days) after percutaneous coronary intervention (PCI).

Methods

This case–control study involved 23 patients with angiographically confirmed EST after PCI (case group) and 92 PCI patients (control group) who did not develop stent thrombosis during a 2-year follow-up. Patients with symptoms and characteristics consistent with OSA (hereinafter referred to as OSA) were identified using the Berlin questionnaire, and the general characteristics of the patients and their treatments as well as outcomes were recorded. The odds ratios (ORs) for OSA were calculated. Additionally, the association between OSA and EST in patients with different conventional cardiovascular risk factors was analyzed.

Results

The crude OR for OSA was 4.17 (95% confidence interval [CI]: 1.60–10.84, P = 0.003). After adjusting for other risk factors of EST, the OR for OSA remained significant. In participants with no or one conventional cardiovascular disease risk factor, we found a significant association between OSA and EST (OR: 17.00, 95% CI: 2.33–124.19, P = 0.005).

Conclusion

OSA is an independent risk factor for EST. This conclusion was further supported by the finding that in patients with few conventional cardiovascular risk factors, the contribution of OSA to EST was more obvious.

Risk of Obstructive Sleep Apnea and Its Association with Cardiovascular and Noncardiac Vascular Risk in Patients with Rheumatoid Arthritis: A Population-based Study

OBJECTIVE

To define the incidence of obstructive sleep apnea (OSA) in patients with rheumatoid arthritis (RA) and determine whether OSA diagnosis predicts future cardiovascular disease (CVD) and noncardiac vascular events.

METHODS

Medical information pertaining to RA, OSA, CVD, and vascular diagnoses was extracted from a comprehensive medical record system for a geographically defined population of 813 patients previously diagnosed with RA and 813 age- and sex-matched comparator subjects.

RESULTS

The risk for OSA in persons with RA versus comparators was elevated, although not reaching statistical significance (HR 1.32, 95% CI 0.98-1.77; p = 0.07). Patients with RA were more likely to be diagnosed with OSA if they had traditional risk factors for OSA, including male sex, current smoking status, hypertension, diabetes, dyslipidemia, and increased body mass index. Features of RA disease associated with OSA included large joint swelling and joint surgery. Patients with RA with decreased renal function were also at higher risk of OSA. The increased risk of overall CVD among patients with RA who have OSA was similar to the increased CVD risk associated with OSA in the comparator cohort (interaction p = 0.86). OSA diagnosis was associated with an increased risk of both CVD (HR 1.9, 95% CI 1.08-3.27), and cerebrovascular disease (HR 2.4, 95% CI 1.14-5.26) in patients with RA.

CONCLUSION

Patients with RA may be at increased risk of OSA secondary to both traditional and RA-related risk factors. Diagnosis with OSA predicts future CVD in RA and may provide an opportunity for CVD intervention.

Sleep-disordered breathing in heart failure: facts and numbers

Sleep‐disordered breathing has a high prevalence in the general population, but is especially prominent in patients with heart failure (HF). HF and sleep‐disordered breathing share a bidirectional relationship, with sleep‐disordered breathing being both cause and effect of poor cardiac functioning. The high inter‐individual variability of symptom presentation can impede the clinical diagnostic process. Polysomnography is the gold‐standard method of diagnosing sleep‐disordered breathing. Therapy of sleep‐disordered breathing should always consist of optimizing the treatment of the underlying disorder of HF. Additional therapeutic measures include continuous positive airway pressure ventilation therapy. New therapeutic options using neurostimulation are yielding promising results; however, long‐term benefits still need to be confirmed.

Sustained apnea induces endothelial activation

BACKGROUND

Apnea diving has gained worldwide popularity, even though the pathophysiological consequences of this challenging sport on the human body are poorly investigated and understood. This study aims to assess the influence of sustained apnea in healthy volunteers on circulating microparticles (MPs) and microRNAs (miRs), which are established biomarkers reflecting vascular function.

HYPOTHESIS

Short intermittent hypoxia due to voluntary breath-holding affects circulating levels of endothelial cell-derived MPs (EMPs) and endothelial cell-derived miRs.

METHODS

Under dry laboratory conditions, 10 trained apneic divers performed maximal breath-hold. Venous blood samples were taken, once before and at 4 defined points in time after apnea. Samples were analyzed for circulating EMPs and endothelial miRs.

RESULTS

Average apnea time was 329 seconds (±103), and SpO₂ at the end of apnea was 79% (±12). Apnea was associated with a time-dependent increase of circulating endothelial cell-derived EMPs and endothelial miRs. Levels of circulating EMPs in the bloodstream reached a peak 4 hours after the apnea period and returned to baseline levels after 24 hours. Circulating miR-126 levels were elevated at all time points after a single voluntary maximal apnea, whereas miR-26 levels were elevated significantly only after 30 minutes and 4 hours. Also miR-21 and miR-92 levels increased, but did not reach the level of significance.

CONCLUSIONS

Even a single maximal breath-hold induces acute endothelial activation and should be performed with great caution by subjects with preexisting vascular diseases. Voluntary apnea might be used as a model to simulate changes in endothelial function caused by hypoxia in humans.

Is C-reactive protein a marker of obstructive sleep apnea?: A meta-analysis

BACKGROUND

Obstructive sleep apnea (OSA) is a common disease, distinguished by recurrent episodes of upper airway obstruction during sleep, with an inflammatory component. C-reactive protein (CRP) and high-sensitivity C-reactive protein (hs-CRP) are markers of systemic inflammation and may serve as biomarkers of OSA.

METHODS

Scientific studies published from January 1, 2006, to January 1, 2016 were obtained via searches of PubMed, Embase, SCI, and China National Knowledge Internet (CNKI) using relevant terms. Studies concerning serum CRP level/ hs-CRP in OSA patients were reviewed by 2 independent reviewers. Studies were included if they conform with our specific criteria of inclusion. Eligible studies were subjected to quality review, data extraction, and meta-analysis by using RevMan (version 5.2) and STATA (version 12.0).

RESULTS

There were 15 studies that met inclusion criteria that included a total of 1297 subjects. Meta-analysis revealed that serum CRP levels in the OSA group were 1.98 mmol/L higher than those in control group (95% confidence interval: 1.39-2.58, P < .01). Similarly, serum hs-CRP levels in the OSA group were 1.57 mmol/L higher than that in the control group (95% confidence interval: 0.96-2.18, P < .01). Subgroup analysis showed greater differences between OSA patients and controls in the setting of obesity (body mass index)> = 30. The total weighted mean difference (WMD) between OSA and controls within the subgroup of subjects who had a CRP was 2.10; for hs-CRP, the WMD was 2.49. Comparing OSA patients of mean apnea hypopnea index> = 15 and controls, the total WMD for the CRP subgroup was 2.19; for the hs-CRP subgroup, the WMD was 1.70.

CONCLUSION

In our meta-analysis, serum CRP/hs-CRP levels were discovered to be higher in OSA patients compared with control subjects. Those with higher body mass index and apnea hyponea index demonstrated larger differences in CRP/hs-CRP levels. These data are consistent with an inflammatory component of OSA pathophysiology and support the role of CRP/hs-CRP as a biomarker in this disease.