Effect of continuous positive airway pressure on homocysteine levels in patients with obstructive sleep apnea: a meta-analysis

Purpose

Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea hypopnea syndrome (OSAHS), but previous studies assessing the effect of CPAP on homocysteine (HCY) in patients with OSAHS yielded conflicting results. In this study, we conducted a meta-analysis to determine whether CPAP therapy could reduce plasma HCY levels.

Methods

Searches of PUBMED, SCI, and Elsevier databases were completed. Studies of adult patients with OSAHS who reported HCY levels pre- and post-CPAP treatment were collected by two independent reviewers. RevMan (version 5.2) and STATA (version 12.0) were used to perform data synthesis.

Results

A total of 6 studies involving 206 participants were included. Meta-analysis showed that the total weighted mean difference (WMD) for HCY levels was ?0.62 units (95 % confidence interval (CI) ?1.21 to ?0.04, P?P?>?0.05), but it was significantly reduced after 3 months therapy (WMD, ?1.22, 95 % CI ?2.07 to ?0.38,P?Conclusions This meta-analysis suggests that HCY levels were significantly reduced by CPAP therapy in patients with OSAHS and the HCY levels may be clinically recognized as a valuable indicator for OSAHS treatment, but the clinical significance of this finding as it relates to cardiovascular risk reduction in OSAHS patients warrants further study.     

Self-efficacy contributes to individual differences in subjective improvements using CPAP

Purpose  

Continuous positive airway pressure (CPAP) improves depressive symptoms and daytime sleepiness in patients with obstructive sleep apnea (OSA). However, there is variability in response to CPAP. This study examined individual differences in the daily associations between CPAP use and improvements in affect and sleepiness patients beginning CPAP.     

The association between continuous positive airway pressure therapy and liver disease development in obstructive sleep apnea/hypopnea syndrome patients: a nationwide population-based cohort study in Taiwan

Purpose

Studies on the association between continuous positive airway pressure (CPAP) treatment and liver diseases such as non-alcoholic fatty liver disease (NAFLD) and cirrhosis in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS) are limited. To the best of our knowledge, none exists that makes use of a national database in an Asian population. This study aims to evaluate the effects of CPAP treatment on patients with these two disorders in a retrospective, population-based study in Taiwan.

Methods

Using the Taiwan National Health Insurance claims database, this study collected the data of OSAHS patients diagnosed between 2000 and 2008 and divided them into CPAP treatment and non-CPAP treatment groups. All subjects were followed up until 2010. Liver disease incidence and risk were calculated.

Results

The CPAP group had a lower cumulative incidence rate of developing liver disease than the non-CPAP group within the observation periods (p < 0.001). After adjusting for age, gender, urbanization level, and comorbidities, the CPAP treatment group showed a lower risk of developing liver disease compared with the non-CPAP treatment group (sub-aHR of 0.66 (95% CI 0.55–0.80), p < 0.001).

Conclusions

Our observations suggest that CPAP treatment may play an important role to delay the progression of liver disease in OSAHS patients and decreases the incidence of liver disease among OSAHS patients. Thus, CPAP therapy may be a feasible way to decrease the risk of liver disease among patients with OSAHS.

     

CPAP therapy induces favorable short-term changes in epicardial fat thickness and vascular and metabolic markers in apparently healthy subjects with obstructive sleep apnea-hypopnea syndrome (OSAHS)

Background

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is an independent risk factor for hypertension, coronary artery disease, and diabetes mellitus. Epicardial fat has been recently recognized as a new risk factor and active participant on cardiometabolic risk. The aim of this study was to assess an independent relationship between sleep apnea severity, metabolic and vascular markers, and epicardial fat, at baseline and after 3 months of continuous positive airway pressure (CPAP) therapy.

Materials and method

Our study group consisted of 48 patients with suspected OSAHS and no prior history of cardiovascular disease or diabetes mellitus. All patients underwent full overnight polysomnography. Thickness of epicardial and visceral adipose tissue, brachial artery flow-mediated dilation (FMD), carotid intima media thickness (cIMT), pulse wave velocity (PWV), plasma C-reactive protein (CRP) levels, fasting glucose levels, HbA1c, homeostatic model assessment of insulin resistance index (HOMA), and lipid profile were measured at baseline and after 3 months of CPAP use in patients with moderate to severe OSAHS.

Results

In OSAHS patients (Apnea-hypopnea index (AHI) ≥15/h, N?=?28), epicardial fat correlated with fasting glucose (rho?=?0.406, p?=?0.04) and HOMA (rho?=?0.525, p?=?0.049) but was not associated with visceral fat (rho?=?0.126, p?=?0.595). Epicardial adipose tissue (EAT) (p?=?0.022) increased across AHI severity along with PWV (p?=?0.045) and carotid intima media thickness (IMT) (p?=?0.034) while FMD (p?=?0.017) decreased. Therapy with CPAP reduced both epicardial (p?<?0.001) and visceral fat (p?=?0.001). Alterations in epicardial fat across the follow-up were associated with changes in PWV (p?=?0.026) and HOMA (p?=?0.037) independently of major confounders.

Conclusions

Epicardial fat thickness was associated with OSA severity and may be an additional marker of cardiovascular risk as well as of future diabetes in these patients. CPAP therapy reduced epicardial fat, suggesting its potentially beneficial role in reducing cardiometabolic risk in OSA patients.

     

Predictive equations for CPAP titration in OSAS patients

Background  

Continuous positive airway pressure (CPAP) is the elective treatment of obstructive sleep apnea. The therapeutic level of CPAP is generally established by manual titration or an auto CPAP device, but an alternative way involves the use of predictive formulas. The aim of the present study was to test the difference between mathematical equations and CPAP or auto CPAP in terms of therapeutic pressure.     

Predicting optimal CPAP by neural network reduces titration failure: a randomized study

Purpose  

Continuous positive airway pressure (CPAP) is considered the standard therapy for obstructive sleep apnea syndrome. In the absence of standard protocol, CPAP titration may be unsuccessful. The purpose of this study was to test the hypothesis that application of an artificial neural network (ANN) to CPAP titration would achieve an optimal CPAP pressure within a shorter time interval and would lead to a decrease in CPAP titration failure.     

Effects of continuous positive airway pressure on blood pressure and daytime sleepiness in obstructive sleep apnea patients with coronary heart diseases under optimal medications

Background  

Continuous positive airway pressure (CPAP) is an effective therapy for obstructive sleep apnea (OSA). However, for patients who already have OSA and coronary heart diseases (CHD) with optimal medications, whether CPAP can reduce the blood pressure (BP) is not clear. This is a controlled study to evaluate the effects of CPAP on BP in Chinese cohorts with CHD under optimal medications.     

Endothelial injury markers before and after nasal continuous positive airway pressure treatment for obstructive sleep apnoea hypopnoea syndrome

Purpose

The purpose of this study was to evaluate whether serum amyloid A (SAA), C-reactive protein (CRP), vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) levels are elevated in obstructive sleep apnoea hypopnoea syndrome (OSAHS), and whether they change following acute- and medium-term CPAP treatment.

Methods

Consecutive subjects (n?=?40) referred to the Sleep Disordered Breathing Unit were included in the research. Sera were sampled in the afternoon prior to an in-hospital limited-channel sleep study and on the next morning. Those diagnosed with OSAHS were commenced on CPAP and had further blood samples collected in the morning after the first night and then after a month of treatment.

Results

We had 20 subjects with moderate/severe OSAHS (mean ± SD), 4 % desaturation rate (4 % DR) 44.3?±?31.4 events/h, and 20 comparator subjects with symptoms but negative sleep studies, 4 % DR 5.6?±?2.9 events/h. There was no difference in the morning and afternoon vascular injury marker levels between the OSAHS and comparator groups. However, CRP (6.52?±?9.53 vs. 5.58?±?8.47, p?=?0.04) and VCAM-1 (366.30?±?90.11 vs. 339.60?±?95.87, p?=?0.02) levels showed significant diurnal variation within the OSAHS group with higher afternoon levels compared to morning measurements. There were no changes in any of the vascular injury marker levels following CPAP.

Conclusions

This study demonstrates that OSAHS leads to endothelial dysfunction as reflected by higher afternoon than morning CRP and VCAM-1 levels. However, despite a good CPAP compliance, a month of treatment does not decrease vascular injury marker levels.     

Spousal involvement in CPAP adherence among patients with obstructive sleep apnea

Purpose  

To determine the effects of spousal involvement on continuous positive airway pressure (CPAP) adherence and response to CPAP problems in male patients with obstructive sleep apnea (OSA).     

Adaptive pressure support servoventilation: a novel treatment for residual sleepiness associated with central sleep apnea events

Objective  

Nasal continuous positive airway pressure (nCPAP) usually reduces sleepiness in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). However, even with regular use of nCPAP, some OSAHS patients experience residual sleepiness (RS). The aim of this study was to evaluate the efficacy of adaptive servoventilation (ASV) on RS in OSAHS patients.     

Auto bi-level with pressure relief during exhalation as a rescue therapy for optimally treated obstructive sleep apnoea patients with poor compliance to continuous positive airways pressure therapy—a pilot study

Background  

Continuous positive airways pressure (CPAP) is the accepted therapy for obstructive sleep apnoea (OSA), but compliance is variable. We hypothesised that an auto bi-level device with pressure relief during exhalation (auto bi-level) would treat OSA as well as CPAP and that transitioning non-compliant CPAP patients without modifiable causes of poor compliance to this device would improve compliance and clinical outcomes.     

阻塞性睡眠呼吸暂停低通气综合征患者呼吸调节的家族聚集性研究

目的　探讨呼吸调节异常是否是引起阻塞性睡眠呼吸暂停低通气综合征 (OSAHS)家族聚集性的原因。方法　对 10例重度OSAHS患者、其一级亲属 16名及单纯肥胖者 14例进行睡眠监测并测定低氧通气反应 (HVR)、高碳酸通气反应 (HCVR)。对OSAHS患者进行持续气道正压通气(CPAP)治疗 ,在治疗的第 1、2、3个月复查HVR和HCVR。结果　 (1)OSAHS患者亲属的呼吸暂停及低通气指数 (AHI)为 (2 8 4± 39 1)次 /h ,出现习惯性打鼾、白天嗜睡的比例分别为 10 0 %和 90 % ,与对照组相比明显增高 (分别为P <0 0 5 ,P <0 0 1,P <0 0 1)。 (2 )亲属中无论是否有OSAHS ,其HVR、HCVR分别为 (- 19± 2 4 )cmH2 O、(0 31± 0 35 )cmH2 O/mmHg ,与对照组比较差异无显著性 (P >0 0 5 )。 (3)经CPAP治疗后 ,OSAHS患者的HVR、HCVR恢复正常。结论　OSAHS有家族聚集性 ,但这一聚集性与遗传性呼吸调节异常无关     

Infertility and obstructive sleep apnea: the effect of continuous positive airway pressure therapy on serum prolactin levels

Background  

Obstructive sleep apnea disease (OSA) is associated with a myriad of endocrine adverse effects. Changes in the serum prolactin (PRL) secretion in OSA are thought to be related to the hypoxic stress and subsequently to result in reversible changes with effective continuous positive airway pressure (CPAP) therapy. Due to current disagreements on this topic, we investigated the effect of CPAP therapy on the serum PRL in patients with OSA, using the most accurate CPAP compliance assessment to date     

Accuracy of autotitrating CPAP to estimate the residual Apnea–Hypopnea Index in patients with obstructive sleep apnea on treatment with autotitrating CPAP

Objective  

Autotitrating continuous positive airway pressure (auto-CPAP) devices now have a smart card (a pocket-sized card with embedded integrated circuits which records data from the CPAP machine such as CPAP usage, CPAP pressure, large leak, etc.) which can estimate the Apnea–Hypopnea Index (AHI) on therapy. The aim of this study was to determine the accuracy of auto-CPAP in estimating the residual AHI in patients with obstructive sleep apnea (OSA) who were treated with auto-CPAP without a CPAP titration study.     

Quality of life,compliance, sleep and nasopharyngeal side effects during CPAP therapy with and without controlled heated humidification

Purpose  

To determine the effect of a controlled heated breathing tube humidifier (cHH) on the quality of life (QOL), compliance and nasopharyngeal side effects during continuous positive airway pressure (CPAP) therapy in patients with obstructive sleep apnea syndrome (OSAS) in comparison with conventional CPAP.     

Combined oral appliance and positive airway pressure therapy for obstructive sleep apnea: a pilot study

Background  

The high efficacy of continuous positive airway pressure (CPAP) in treating obstructive sleep apnea (OSA) is limited by poor compliance often related to pressure intolerance. Mandibular advancement devices (MADs) are proven alternative therapy although not universally effective. A combination of nasal CPAP and MAD may provide another option for CPAP-intolerant patients with incomplete response to MAD.     

Determinants of continuous positive airway pressure compliance in a group of Greek patients with obstructive sleep apnea

ObjectiveThe aim of the study was to investigate the patients' characteristics that correlate with greater compliance to CPAP use.MethodsPatients diagnosed with OSAHS and treated with CPAP, who had at least one follow-up visit in the Sleep Clinic during one year, were included in the study. Demographic data, history of symptoms, comorbidities, Body Mass Index (BMI), Epworth Sleepiness Scale questionnaire (ESS), were obtained from patients before and under CPAP use. All variables were correlated with average daily CPAP use. Objective and subjective compliance were estimated and a cut off point of 4.5 h/d was used to distinguish ‘more compliant’ from less ‘compliant’ patients.ResultsNinety eight patients, with a mean age (± SD) of 55.5 (± 11.1) years were examined. Patients' symptoms improved after CPAP use. The objective compliance was 5.3 ± 1.6 h/d whereas the subjective compliance was higher. Only 25% of patients were characterized as ‘more compliant’. Compliance was positively correlated in a significant way with age and female gender, and negatively correlated with neck circumference, preexisting nasal problems and minimum saturation during sleep. Patients with arterial hypertension showed a trend to better compliance. Weight gain was more frequently observed in ‘less compliant’ patients.ConclusionTo our knowledge this is the first study examining parameters of CPAP compliance in a Greek population of OSAHS patients. Age, gender and minimum saturation during sleep were related to better compliance whereas higher neck circumference and preexisting nasal problems were the parameters related to a worse adherence to treatment.     

The impact of split-night versus traditional sleep studies on CPAP compliance

Background  

Split-night polysomnography allows for the diagnosis of obstructive sleep apnea and titration of continuous positive airway pressure in a single study. However, there is concern that split-night studies do not provide sufficient time for optimal continuous positive airway pressure (CPAP) titration, which may lead to a poor initial experience with CPAP and potentially, worse adherence. Our goal was to determine whether CPAP use, after a split-night examination, is comparable to the use following separate diagnostic and titration studies.     

Clinical outcomes related to interface type in patients with obstructive sleep apnea/hypopnea syndrome who are using continuous positive airway pressure

STUDY OBJECTIVES: To evaluate the effect of interface on objective compliance, patient satisfaction, adverse effects, quality of life, and residual sleep-disordered breathing in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS) using continuous positive airway pressure (CPAP). DESIGN: Randomized, cross-over. SETTING: Two suburban community-based hospital sleep laboratories. PATIENTS: Data were collected on 39 patients with OSAHS (mean age, 48.7 years), in whom CPAP was a novel treatment. INTERVENTIONS: Interventions were nasal pillows (Breeze; Mallinckrodt Corporation; Minneapolis, MN) and nasal mask (Contour; Respironics; Murrysville, PA). MEASUREMENTS AND RESULTS: Outcomes assessed at the completion of each 3-week treatment period were objective compliance, adverse effects, and satisfaction with CPAP (CPAP questionnaire), daytime sleepiness (Epworth sleepiness scale [ESS]), quality of life (Functional Outcomes of Sleep Questionnaire [FOSQ]), sleep diary, and residual sleep-disordered breathing (apnea-hypopnea index [AHI]). Patients were randomly assigned to use the nasal pillows or the nasal mask following laboratory titration and initiated on CPAP (pressure range, 5 to 14 cm H(2)O). The percentage of days utilized favored the nasal pillows (94.1% vs 85.7%; p = 0.02), but minutes of use per night did not differ (nasal pillows, 223 min; nasal mask, 288 min). ESS scores were lower and the FOSQ total scores were higher following CPAP treatment (p < 0.001), but no differential treatment effects were noted. Fewer adverse effects, less trouble getting to sleep and staying asleep, and less air leak were reported with nasal pillows (p < 0.04). The mean +/- SD pretreatment AHI (47.1 +/- 35.1/h) was significantly lower following treatment with CPAP for both types of interface (nasal pillows, 10.2 +/- 9.8/h; nasal mask, 7.0 +/- 7.7/h; p < 0.001). CONCLUSIONS: Nasal pillows are a well-tolerated and effective interface for OSAHS patients receiving CPAP at < or = 14 cm H(2)O. Use of nasal pillows was associated with fewer adverse effects and better sleep quality during the first 3 weeks of CPAP therapy. Further investigation is needed to determine whether interface type affects long-term CPAP use.     

Higher dose of warfarin for patients with pulmonary embolism complicated by obstructive sleep apnea hypopnea syndrome

Background

The concomitant prevalence of obstructive sleep apnea hypopnea syndrome (OSAHS) and pulmonary embolism (PE) is strikingly high, and therefore we studied the patients with PE to determine whether those who had OSHAS required greater warfarin doses to achieve a therapeutic international normalized ratio (INR).

Methods

By using computer tomographic pulmonary angiography or pulmonary angiography, we identified and recruited 97 patients with PE and all underwent polysomnography. Warfarin was initiated at a dose of 3 mg/day and modified to adjust the INR to the range of 2.0–3.0.

Results

OSAHS patients (n = 32) required a significantly higher dose of warfarin than their non-OSAHS counterparts (5.01 mg vs 3.61 mg, P < .001). This difference still existed between the two groups after adjusting for covariates (achieved INR value and weight). Logistic analysis suggested that OSAHS was an independent risk factor for high dose warfarin (OR 5.715, P < .001). On admission, OSAHS patients had a lower mean value of INR and prothrombin time but higher plasminogen (PLG) activity compared to non-OSAHS patients. Other coagulation indices were not significantly different between the two groups. Except for the PLG activity (r = .273, P = .026), the correlation between the warfarin dose and the baseline coagulating indices wasn't significant.

Conclusions

Our findings indicate that factors associated with OSAHS, such as hypercoagulation, may explain the need for higher doses of warfarin in treating patients with PE.