Obstructive Sleep Apnea and Cardiovascular Disease: Where Do We Stand?

Obstructive sleep apnea is common in adults with cardiovascular disease. Accumulating evidence suggests an association between obstructive sleep apnea and cardiovascular disease independent of the traditionally recognized cardiovascular disease risk factors. Observational studies indicate that obstructive sleep apnea is a risk factor for development of cardiovascular disease and that alleviation of obstructive events with positive airway pressure may improve cardiovascular disease outcomes. However, recent randomized controlled trials have not supported the beneficial effect of positive airway pressure in cardiac populations with concomitant obstructive sleep apnea. Some evidence suggests that the relationship between obstructive sleep apnea and traditionally recognized cardiovascular disease risk factors is bidirectional, suggesting that patients with cardiovascular disease may also develop obstructive sleep apnea and that efficient treatment of cardiovascular disease may improve obstructive sleep apnea. Recent data also indicate that the apnea-hypopnea index, which is commonly used as a diagnostic measure of obstructive sleep apnea severity, has limited value as a prognostic measure for cardiovascular disease outcomes. Novel markers of obstructive sleep apnea-associated hypoxic burden and cardiac autonomic response seem to be strong predictors of adverse cardiovascular disease outcomes and response to treatment of obstructive sleep apnea. This narrative review and position paper from the Turkish Collaboration of Sleep Apnea Cardiovascular Trialists aims to update the current evidence about the relationship between obstructive sleep apnea and cardiovascular disease and, consequently, raise awareness for health professionals who deal with cardiovascular and respiratory diseases to improve the ability to direct resources at patients most likely to benefit from treatment of obstructive sleep apnea and optimize treatment of the coexisting cardiovascular diseases. Moreover, the Turkish Collaboration of Sleep Apnea Cardiovascular Trialists aims to contribute to strengthening the efforts of the International Collaboration of Sleep Apnea Cardiovascular Trialists in this context.

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.

Relationships between quality of life, sleep problems, and sleep quality in patients with chronic idiopathic urticaria.

BACKGROUND: In this study, we aimed to evaluate the sleep quality among chronic urticaria patients using the Chronic Urticaria Quality-of-Life Questionnaire (CU-Q2oL), sleep quality assessment tools, and polysomnography and to investigate any relationships between the obtained results. METHODS: The study included 21 patients diagnosed with chronic spontaneous urticaria and 19 healthy controls. We recorded the patients' sleep quality data, including CU-Q2 oL, Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), and polysomnography results. RESULT: Patients in the chronic urticaria group were more likely to have an ESS score of ≥10 (52.4% vs. 5.3%, p = 0.004) and an apnea-hypopnea index of ≥5 (44.4% vs. 5.3%, p = 0.017) compared to the control group. In the patient group, the CU-Q2 oL total score was positively correlated with sleep latency (r = 0.713, p = 0.004) and PSQI-C1 score (r = 0.726, p = 0.005), while it was negatively correlated with urticaria duration (r = -0.579, p = 0.015), apnea-hypopnea index (r = -0.607, p = 0.021), longest apnea duration (r = -0.583, p = 0.029), total number of respiratory events (r = -0.618, p = 0.018), and apnea count (r = -0.686, p = 0.007). CONCLUSION: We conclude that sleep-related problems exist among a considerably large proportion of patients with chronic spontaneous urticaria.

Evaluation of Acromegaly patients with sleep disturbance related symptoms.

BACKGROUND AND OBJECTIVES: It is known that the prevalence of obstructive sleep apnea (OSA) is increased in acromegaly. Craniofacial anomalies, macroglossia, and thickening of the laryngeal wall caused by the increase in soft tissue in these patients lead to OSA. Also, the increase in growth hormone can trigger central apnea by causing a decrease in respiratory drive. Determining the polysomnographic characteristics of acromegaly patients is important to reveal the effect of these mechanisms. METHODS: The demographic and polysomnographic characteristics of 33 acromegaly patients who underwent polysomnography (PSG) with suspicion of sleep disorders between 2011 and 2018 in the sleep laboratory of our hospital were retrospectively analyzed. One of the patients was excluded from the analysis because PSG was performed in the postoperative period. The remaining 32 patients with active acromegaly were grouped according to their gender and the presence of OSA and compared with statistical methods in terms of polysomnographic and clinical features. RESULTS: OSA (AHI>5) was detected in 78.1% of 32 active acromegaly patients (18 females, 14 males) who underwent PSG with suspicion of sleep-disordered breathing. Moderate-severe OSA (62.5%) was found in most patients, and there was no difference between the sexes in terms of OSA detection rate and OSA severity. Respiratory events appear to be predominantly obstructive hypopneas. Also, the polysomnographic features of female and male acromegaly patients with OSA were found to be similar. It is seen that the OSA group is similar to the group with simple snoring in terms of body mass index (BMI), but is statistically significantly older (p=0,007). A positive correlation was found between age and AHI in pairwise correlation analysis (r:0,426 p:0,015, respectively). CONCLUSION: Considering that the prevalence of OSA in the population is approximately 5%, our results show that the risk of OSA in acromegaly increases, and obstructive pathways are effective in this increase. The probability of OSA occurrence and polysomnographic features between the genders are similar. Although the median BMI of the patients with and without OSA was similar, the median age was higher in the group with OSA, middle-aged acromegaly patients should be evaluated in terms of OSA even if there is no obvious obesity.

Obstructive sleep apnea is a determinant of asthma control independent of smoking, reflux, and rhinitis.

Background: Asthma control is defined as to what extent manifestations of asthma can be observed in a patient or have been reduced or removed by treatment. Regular use of asthma treatments, correct inhaler technique, adequate information provided about the patient's diseases and medicines, and patient-clinician collaboration aid asthma control. Asthma shares risk factors and links in the pathogenesis with obstructive sleep apnea (OSA), and OSA may aggravate asthma symptoms. Objective: To assess the risk of OSA for asthma control. Methods: The study was carried out in subjects with asthma who were followed up at specific time points and who used asthma medication regularly and with an appropriate inhaler technique. An asthma control test and a questionnaire were used to determine the asthma control levels and OSA risk of the subjects. Results: With regard to the questionnaire scoring, 77 of 137 subjects with asthma had a low OSA risk and 60 had a high OSA risk. The proportion of the subjects with a high OSA risk (p < 0.001) and were smokers (p = 0.020) were significantly higher in the subjects with uncontrolled asthma than in those with controlled asthma. Logistic regression analysis showed that the variables that affect asthma control status were the risk of OSA and obesity. The subjects with a low OSA risk were more likely to have controlled asthma than those with a high OSA risk (odds ratio 7.896 [95% confidence interval, 2.902-21.487]; p < 0.001). Conclusion: In the subjects with asthma and who adhered to therapy and used inhalers with the correct technique, a high risk of OSA was associated with poor control of their asthma. This association was independent of other factors, including rhinitis, gastroesophageal reflux, and smoking.

The Evaluation of APAP Titration Results: Good Titration Versus TECSA and Unacceptable Titration.

OBJECTIVE: The first choice for treatment in severe and moderate obstructive sleep apnea syndrome (OSAS) is positive airway pressurem (PAP) devices. However, despite proper titration, respiratory events may persist, while central respiratory events may increase or emerge for some patients. The primary aim of this study is to compare the clinical, demographic, and polysomnographic features of patients with different titration results. MATERIAL AND METHODS: The patients who underwent automatic PAP (APAP) titration with the nasal mask in our clinic due to moderate or severe OSAS in 2017 were included in the study. The clinical, demographic, and polysomnographic characteristics of patients with successful (good) titration, "unacceptable" APAP titration, and treatment-emergent central apnea syndrome (TECSA), were recorded retrospectively and evaluated comparatively with statistical methods. RESULTS: Out of 942 titration tests with APAP, 37 patients were diagnosed as TECSA (3.9%), while unacceptable (unsuccessful) titrationresults were seen only in 20 patients (2.1%). For the successful titration group, 44 consecutive patients were recruited. In the TECSA group, the central apnea index and minimum SpO2 were higher during the diagnostic polysomnography (PSG). In the unacceptable titration group, the baseline minimum SpO2 was lower. The lower sleep efficiency, lower stage N3 sleep, and longer rapid eye movement (REM) and sleep latencies were observed in the TECSA group during the titration test. The diagnostic accuracy of PAP device recordings was found to be moderate (kappa value: 0.533). CONCLUSION: The baseline polysomnographic features, including higher central apnea index and minimum SpO2, may raise suspicion for titration failures for which a laboratory-based titration can be scheduled.

Practical and rapidly-implemented parameters for assessing APAP titration failure.

BACKGROUND: This study aimed to show the predictive value of simple polysomnographic parameters including latency of deep sleep (nREM3), latency of rapid eye movement sleep (REM), and minimum oxygen saturation (SpO2) for predicting failure of autoadjusting positive airway pressure (APAP) titration. METHODS: Out of 1470 patients with moderate to severe obstructive sleep apnea syndrome (OSAS) who underwent APAP titration between July 1, 2016, and December 31, 2017, 22 patients with titration failure were enrolled in the study. The demographic and polysomnographic characteristics of this group were compared with 44 patients with an adequate APAP titration who were matched with the titration failure group by age, sex, and OSAS severity. The periods between the start of sleep and the start of REM and nREM3 stages were noted as REM latency and nREM3 latency, respectively. RESULTS: The between group differences in the parameters including nREM3 latency, REM latency, and minimum SpO2 during the titration test were statistically significant (p = 0.004, p = 0.008, p <0.001 respectively). Possible threshold values to predict failure of APAP titration were found as 40 min and 135 min for nREM3 and REM latencies, respectively. The best threshold for minimum SpO2 was 86% with an 86.4% of sensitivity. Despite the high negative predictive values (81% for nREM3 latency, 75% for REM latency), the sensitivities (63.6% for nREM3 latency, 54.5% for REM latency) of the prior parameters in determining titration failure were relatively low. CONCLUSION: The minimum SpO2 < 86% can be used as a readily available indicator of APAP titration failure. nREM3 and REM latencies may be regarded as supplementary indicators in detecting the patients who may need an advanced PAP device.

An Integrated Approach Toward the Clinical and Polysomnographic Characteristics of OSA Accompanying IPF.

OBJECTIVES: Coincidance of idiopathic pulmonary fibrosis (IPF) and the obstructive sleep apnea syndrome (OSA) may have important effects on the pathogenesis of each other. Our aim is to define clinical characteristics of patients with IPF and OSA and to identify a combined index to determine the severity of both diseases together. MATERIALS AND METHODS: The clinical and polysomnographic characteristics of 22 patients with OSA and IPF who underwent nocturnal polysomnography (NPSG) were retrospectively evaluated and compared with 23 OSA patients without any other pulmonary comorbidities. RESULTS: We demonstrated high frequency of OSA within our study group (94,7%) all of whom had at least one of the majör symptoms of OSA. Lower AHI, lower neck circumference, higher percentage of deep sleep (nREM3) and less comorbidities were observed in the study group when compared to OSA with no other pulmonary comorbidities (p<0,05). When restaged into a compound index according to the gender, age and physiology (GAP) index, the patients with mild IPF and OSA showed the same life and sleep quality with the patients who have higher GAP index. CONCLUSION: All patients with IPF must be questioned for the major symptoms of sleep related breathing disorders (SRBD). Clinical suspicion for OSA must prompt NPSG. With the presence of moderate-severe OSA, the life and sleep quality of patients with mild IPF can be at the same level of patients with severe IPF.

Increased age adversely affects the therapeutic effect of CPAP treatment for olfactory functions.

PURPOSE: The aim of this study was to compare olfactory functions pre- and post-CPAP treatment in patients with moderate to severe OSA, and to evaluate the factors that cause changes in olfactory functions. METHODS: Twenty-two patients who had completed regular usage of CPAP treatment for 2 months were included in this prospective study. Olfactory tests using Sniffin' Sticks were performed pre- and post-treatment. RESULTS: The mean age of the subjects was 47.6 ± 9.5 years. We did not find a significant change in olfactory functions after 2 months of CPAP treatment in our study group. When the patients were divided into two groups-those whose olfactory functions showed improvement and those whose functions did not-it was found that the mean age of the patients whose olfactory functions did not improve was significantly higher statistically. A significant adverse correlation was found between age and post-treatment olfactory functions, specifically in odour threshold and odour identification scores. CONCLUSIONS: Increased age adversely affects the therapeutic effect of CPAP treatment for olfactory functions.

Evaluation of children with chronic cough including obstructive sleep apnea: a single-center experience.

Chronic cough in children may be due to a diverse range of etiologies. We aimed to evaluate children with chronic cough following a standardized cough algorithm and assess obstructive sleep apnea (OSA) as a possible etiology. In addition, cough resolution rates of two different treatment protocols in children with non-specific cough were compared. A total of 237 children referred for chronic cough were assessed and classified according to etiologies. Children with non-specific cough were assigned either in the early-arm (group-1, n = 13) or delayed arm (group-2, n = 23). The presence of OSA was evaluated using a pediatric sleep questionnaire, and polysomnography was handled in indicated patients. Asthma (n = 82) and protracted bacterial bronchitis (PBB) (n = 73) were the most frequent etiologies. Cough resolution was higher in group-1 (100%) compared with group-2 (50%) (absolute risk reduction (rr) = 43.48% [95% CI 21.38-65.58%]). Polysomnography revealed mild (n = 6), moderate (n = 7), or severe (n = 5) OSA in 18 children, with adenoid/adenotonsillary hypertrophy as the leading cause.Conclusion: We recognized asthma and PBB as the most frequent causes of chronic cough in our cohort. Early treatment of patients with high parental anxiety might be beneficial. We also believe that further studies including larger series might eventuate in incorporation of assessment of OSA to standardized algorithms. What is known? • Chronic cough in children may be due to a diverse range of etiologies, including serious respiratory disorders. Thus, its correct diagnosis and treatment are essential. • Although a well-defined reason of chronic cough in adults, obstructive sleep apnea (OSA) has not been been evaluated so far in children with chronic cough. What is new? • We examined OSA for the first time as a possible cause of chronic cough in children and detected OSA with polysomnography in cases who scored high pediatric sleep questionnaire (PSQ) scores. • We believe that studies including larger series might eventuate in incorporation of assessment of OSA to standardized algorithms for children with chronic cough.

Relationship between obstructive sleep apnea syndrome and thyroid diseases.

Obstructive sleep apnea syndrome (OSAS) is a widespread disorder characterized by recurrent, partial, or complete episodes of apnea due to upper airway tract obstruction during sleep. OSAS frequency is likely to increase in hypothyroidism because of obesity, macroglossia, dysfunctional upper respiratory tractus (URT) musculature, deposition of mucopolysaccharides in URT tissues, and decreased ventilatory control. This study examines the relationship between OSAS and thyroid disease in OSAS subjects. This study includes 150 polysomnographically diagnosed OSAS patients (50 mild, 50 moderate, 50 severe OSAS cases) treated at Endocrinology and Metabolism Department of Ankara Numune Training and Research Hospital between January 2010 and May 2011 and 32 non-OSAS control subjects. All patients were given serum TSH, free T3 (fT3), free T4 (fT4), anti thyroid peroxidase (Anti-TPO), and anti-thyroglobulin (anti-TG) tests, as well as thyroid ultrasounds. We did not find any difference in prevalence of hypothyroidism, numbers of nodules and parenchyma heterogenicity determined by ultrasound, between OSAS subgroups and controls (p > 0,05). In this study, functional and ultrasonographic examination of the thyroid gland did not reveal any relationship between OSAS and thyroid disease. We believe hence that long-term follow-up studies can establish the possible significance of routine evaluation of OSAS patients for thyroid disease.