Adherence to CPAP Treatment and the Risk of Recurrent Cardiovascular Events: A Meta-Analysis.

Importance: The effect of continuous positive airway pressure (CPAP) on secondary cardiovascular disease prevention is highly debated. Objective: To assess the effect of CPAP treatment for obstructive sleep apnea (OSA) on the risk of adverse cardiovascular events in randomized clinical trials. Data Sources: PubMed (MEDLINE), EMBASE, Current Controlled Trials: metaRegister of Controlled Trials, ISRCTN Registry, European Union clinical trials database, CENTRAL (Cochrane Central Register of Controlled Trials), and ClinicalTrials.gov databases were systematically searched through June 22, 2023. Study Selection: For qualitative and individual participant data (IPD) meta-analysis, randomized clinical trials addressing the therapeutic effect of CPAP on cardiovascular outcomes and mortality in adults with cardiovascular disease and OSA were included. Data Extraction and Synthesis: Two reviewers independently screened records, evaluated potentially eligible primary studies in full text, extracted data, and cross-checked errors. IPD were requested from authors of the selected studies (SAVE [NCT00738179], ISAACC [NCT01335087], and RICCADSA [NCT00519597]). Main Outcomes and Measures: One-stage and 2-stage IPD meta-analyses were completed to estimate the effect of CPAP treatment on risk of recurrent major adverse cardiac and cerebrovascular events (MACCEs) using mixed-effect Cox regression models. Additionally, an on-treatment analysis with marginal structural Cox models using inverse probability of treatment weighting was fitted to assess the effect of good adherence to CPAP (≥4 hours per day). Results: A total of 4186 individual participants were evaluated (82.1% men; mean [SD] body mass index, 28.9 [4.5]; mean [SD] age, 61.2 [8.7] years; mean [SD] apnea-hypopnea index, 31.2 [17] events per hour; 71% with hypertension; 50.1% receiving CPAP [mean {SD} adherence, 3.1 {2.4} hours per day]; 49.9% not receiving CPAP [usual care], mean [SD] follow-up, 3.25 [1.8] years). The main outcome was defined as the first MACCE, which was similar for the CPAP and no CPAP groups (hazard ratio, 1.01 [95% CI, 0.87-1.17]). However, an on-treatment analysis by marginal structural model revealed a reduced risk of MACCEs associated with good adherence to CPAP (hazard ratio, 0.69 [95% CI, 0.52-0.92]). Conclusions and Relevance: Adherence to CPAP was associated with a reduced MACCE recurrence risk, suggesting that treatment adherence is a key factor in secondary cardiovascular prevention in patients with OSA.

Insomnia disorder: clinical and research challenges for the 21st century.

BACKGROUND AND PURPOSE: Insomnia is a common and debilitating disorder that is frequently associated with important consequences for physical health and well-being. METHODS: An international expert group considered the current state of knowledge based on the most relevant publications in the previous 5 years, discussed the current challenges in the field of insomnia and identified future priorities. RESULTS: The association of trajectories of insomnia with subsequent quality of life, health and mortality should be investigated in large populations. Prospective health economics studies by separating the costs driven specifically by insomnia and costs attributable to its long-term effects are needed. Ignoring the heterogeneity of insomnia patients leads to inadequate diagnosis and inefficient treatment. Individualized interventions should be promoted. More data are needed on both the impact of sleep on overnight effects, such as emotion regulation, and the potential compensatory effort to counteract diurnal impairments. Another gap is the definition of neurocognitive deficits in insomnia patients compared to normal subjects after chronic sleep loss. There are also a number of key gaps related to insomnia treatment. Expert guidelines indicate cognitive-behavioural therapy for insomnia as first-line treatment. They neglect, however, the reality of major healthcare providers. The role of combined therapy, cognitive-behavioural therapy for insomnia plus pharmacological treatment, should be evaluated more extensively. CONCLUSION: Whilst insomnia disorder might affect large proportions of the population, there are a number of significant gaps in the epidemiological/clinical/research studies carried out to date. In particular, the identification of different insomnia phenotypes could allow more cost-effective and efficient therapies.

Surgical management of obstructive sleep apnoea: A position statement of the Australasian Sleep Association.

Surgery for adult obstructive sleep apnoea (OSA) plays a key role in contemporary management paradigms, most frequently as either a second-line treatment or in a facilitatory capacity. This committee, comprising two sleep surgeons and three sleep physicians, was established to give clarity to that role and expand upon its appropriate use in Australasia. This position statement has been reviewed and approved by the Australasian Sleep Association (ASA) Clinical Committee.

Diagnostic accuracy of a questionnaire and simple home monitoring device in detecting obstructive sleep apnoea in a Chinese population at high cardiovascular risk.

BACKGROUND AND OBJECTIVE: OSA is a common condition associated with cardiovascular (CV) morbidity. It remains underdiagnosed globally in part due to the limited availability and technical requirements of polysomnography (PSG). The aim of this study was to test the accuracy of two simple methods for diagnosing OSA. METHODS: Consecutive subjects identified from a community register with high CV risk were invited to complete the Berlin Sleep Questionnaire and undergo simultaneous, home, overnight PSG and ApneaLink device oximetry and nasal pressure recordings. The relative accuracies of the Berlin Questionnaire, oximetry and nasal pressure results in diagnosing PSG-defined moderate-severe OSA were assessed. RESULTS: Of 257 eligible high CV risk subjects enrolled, 190 completed sleep studies and 143 subjects' studies were of sufficient quality to include in final analyses. Moderate-severe OSA was confirmed in 43% of subjects. The Berlin Questionnaire had low overall diagnostic accuracy in this population. However, ApneaLink recordings of oximetry and nasal pressure areas had high diagnostic utility with areas under the receiver operating characteristic curves of 0.933 and 0.933, respectively. At optimal diagnostic thresholds, oximetry and nasal pressure measurements had similar sensitivity (84% vs 86%) and specificity (84% vs 85%). Technical failure was lower for oximetry than nasal pressure (5.8% vs 18.9% of tests). CONCLUSIONS: In patients with high CV risk overnight single-channel oximetry and nasal pressure measurements may provide high diagnostic accuracy and offer an accessible alternative to full PSG.

Developing a screening tool to recognise social determinants of health in Australian clinical settings.

Objective and importance of study: The importance of social determinants for individual health recovery outcomes is well recognised in public health. However, no succinct social health screening (SHS) tool exists that has been developed with information from clinicians and patients. This proof-of-concept study asked health consumer advocates, patients and clinicians about their attitudes towards social determinants of health (SDH) and the usefulness of an SHS tool for collecting these data for use in clinical settings. We then developed a streamlined SHS tool to bring this knowledge to clinicians, and conducted a proof-of-concept trial to check its acceptability with patients and clinicians. METHODS: This qualitative study had two stages. Stage 1 involved focus groups with health consumer advocates and interviews with clinicians about the draft SHS tool. Stage 2 involved refining the SHS tool and piloting it with 50 new patients in anxiety disorder and sleep disorder clinics, which often treat patients living in disadvantaged socio-economic conditions. The tool was evaluated by patients and clinicians. The data were analysed using framework analysis. RESULTS: All interviewees were positive about the benefits of addressing SDH in clinical practice to help reduce health inequities. We developed and refined an SHS tool that could be completed by patients ('self-complete'). CONCLUSION: The response to introducing an SHS tool in clinical settings was positive. Further piloting across diverse clinical settings is required to determine efficacy. This tool promotes public health equity outcomes by improving clinician understanding of individual social circumstances, and has the potential to provide useful epidemiological data on SDH.

The impact of ethnicity on the prevalence and severity of obstructive sleep apnea.

Obstructive sleep apnea (OSA) is a common disorder associated with multiple adverse health consequences and its prevalence is increasing in parallel with rising obesity trends. Early support for ethnic differences in OSA prevalence and severity has been derived from studies of relatively homogenous ethnic groups. However, between-study comparisons are problematic given differing methodologies. Recent large inter-ethnic studies examining different ethnic populations using standardized protocols support the notion that Chinese have an increased OSA prevalence and severity compared to those of European descent. Although the evidence is less clear, some data suggest that Hispanic/Mexican Americans also show higher rates of OSA, while OSA prevalence in African Americans is not dissimilar to that of populations of European ancestry. Of the anatomical traits underlying differences in OSA prevalence and severity between ethnic groups (i.e., obesity, fat distribution, and craniofacial structure) obesity appears to be the most important. The effect of ethnicity on non-anatomical factors (i.e., upper airway muscle responsiveness, arousal threshold, and loop gain) responsible for OSA severity and potentially prevalence is currently unknown and needs further research.

Atrial remodeling in obstructive sleep apnea: implications for atrial fibrillation.

BACKGROUND: There is a known association between obstructive sleep apnea (OSA) and atrial fibrillation (AF); however, how OSA affects the atrial myocardium is not well described. OBJECTIVE: To determine whether patients with OSA have an abnormal atrial substrate. METHODS: Forty patients undergoing ablation of paroxysmal AF and in sinus rhythm (20 with OSA [apnea-hypopnea index ≥ 15] and 20 reference patients with no OSA [apnea-hypopnea index < 15] by polysomnography) were studied. Multipolar catheters were positioned at the lateral right atrium (RA), coronary sinus, crista terminalis, and RA septum to determine the effective refractory period at 5 sites, conduction time along linear catheters at the RA and the coronary sinus, conduction at the crista terminalis, and sinus node function (corrected sinus node recovery time). Biatrial electroanatomic maps were created to determine the voltage, conduction, and distribution of complex electrograms (duration ≥ 50 ms). RESULTS: The groups had no differences in the prevalence of established risk factors for AF. Patients with OSA had the following compared with those without OSA: no difference in effective refractory period (P = .9), prolonged conduction times along the coronary sinus and RA (P = .02), greater number (P = .003) and duration (P = .03) of complex electrograms along the crista terminalis, longer P-wave duration (P = .01), longer corrected sinus node recovery time (P = .02), lower atrial voltage (RA, P <.001; left atrium, P <.001), slower atrial conduction velocity (RA, P = .001; left atrium, P = .02), and more widespread complex electrograms in both atria (RA, P = .02; left atrium, P = .01). CONCLUSION: OSA is associated with significant atrial remodeling characterized by atrial enlargement, reduction in voltage, site-specific and widespread conduction abnormalities, and longer sinus node recovery. These features may in part explain the association between OSA and AF.

Increased severity of lower urinary tract symptoms and daytime somnolence in primary Sjögren's syndrome.

OBJECTIVE: Functional antimuscarinic receptor autoantibodies have recently been described in both primary and secondary Sjögren's syndrome (SS) in a mouse bladder contraction assay. Most patients with these antibodies complained of severe lower urinary tract disturbances, which are not a recognized feature of SS. We compared the severity of self-reported urological symptoms, daytime somnolence, and fatigue between a cohort of patients with primary SS and controls with osteoarthritis (OA). METHODS: Female patients were recruited from rheumatology outpatient clinics at 2 hospitals. The American Urological Symptom Index (AUA-7), Epworth Sleepiness Scale, and FACIT-F fatigue self-administered instruments were employed. Results were obtained for 76 patients with primary SS and 43 controls (response rates 85% and 67%, respectively). The patient groups were matched for parity, hormone replacement and diuretic therapy, and number of bladder operations and urinary tract infections, although OA patients were slightly older. RESULTS: AUA-7 urological symptoms were more severe in patients with primary SS compared to OA controls (p = 0.039). Severe urological symptoms were reported by 61% of primary SS patients compared with 40% of OA controls. This difference was predominantly attributable to bladder irritability associated with urgency (p = 0.015) and not nocturia (p = 0.85). Epworth Sleepiness Scale scores were also more severe in primary SS patients compared to OA controls (p = 0.02), independent of nocturia. The FACIT-F fatigue severity scores were not significantly different between patient groups (p = 0.14). CONCLUSION: Urological symptoms and daytime somnolence may be previously unrecognized symptoms of primary SS. These symptoms are consistent with functional disturbances of muscarinic receptors, possibly mediated by muscarinic receptor autoantibodies.