Effects of Ethnicity on the Prevalence of Obstructive Sleep Apnoea in Patients with Acute Coronary Syndrome: A Pooled Analysis of the ISAACC Trial and Sleep and Stent Study.

BACKGROUND: Obstructive sleep apnoea (OSA) is an emerging risk factor for acute coronary syndrome (ACS). We sought to determine the effects of ethnicity on the prevalence of OSA in patients presenting with ACS who participated in an overnight sleep study. METHODS: A pooled analysis using patient-level data from the ISAACC Trial and Sleep and Stent Study was performed. Using the same portable diagnostic device, OSA was defined as an apnoea-hypopnoea index of ≥15 events per hour. RESULTS: A total of 1961 patients were analysed, including Spanish (53.6%, n=1050), Chinese (25.5%, n=500), Indian (12.0%, n=235), Malay (6.1%, n=119), Brazilian (1.7%, n=34) and Burmese (1.2%, n=23) populations. Significant differences in body mass index (BMI) were found among the various ethnic groups, averaging from 25.3kg/m2 for Indians and 25.4kg/m2 for Chinese to 28.6kg/m2 for Spaniards. The prevalence of OSA was highest in the Spanish (63.1%), followed by the Chinese (50.2%), Malay (47.9%), Burmese (43.5%), Brazilian (41.2%), and Indian (36.1%) patients. The estimated odds ratio of BMI on OSA was highest in the Chinese population (1.17; 95% confidence interval: 1.10-1.24), but was not significant in the Spanish, Burmese or Brazilian populations. The area under the curve (AUC) for the Asian patients (ranging from 0.6365 to 0.6692) was higher than that for the Spanish patients (0.5161). CONCLUSION: There was significant ethnic variation in the prevalence of OSA in patients with ACS. The magnitude of the effect of BMI on OSA was greater in the Chinese population than in the Spanish patients.

Obstructive Sleep Apnea and Cardiovascular Events After Percutaneous Coronary Intervention.

BACKGROUND: There is a paucity of data from large cohort studies examining the prognostic significance of obstructive sleep apnea (OSA) in patients with coronary artery disease. We hypothesized that OSA predicts subsequent major adverse cardiac and cerebrovascular events (MACCEs) in patients undergoing percutaneous coronary intervention. METHODS AND RESULTS: The Sleep and Stent Study was a prospective, multicenter registry of patients successfully treated with percutaneous coronary intervention in 5 countries. Between December 2011 and April 2014, 1748 eligible patients were prospectively enrolled. The 1311 patients who completed a sleep study within 7 days of percutaneous coronary intervention formed the cohort for this analysis. Drug-eluting stents were used in 80.1% and bioresorbable vascular scaffolds in 6.3% of the patients, and OSA, defined as an apnea-hypopnea index of ≥15 events per hour, was found in 45.3%. MACCEs, a composite of cardiovascular mortality, nonfatal myocardial infarction, nonfatal stroke, and unplanned revascularization, occurred in 141 patients during the median follow-up of 1.9 years (interquartile range, 0.8 years). The crude incidence of an MACCEs was higher in the OSA than the non-OSA group (3-year estimate, 18.9% versus 14.0%; p=0.001). Multivariate Cox regression analysis indicated that OSA was a predictor of MACCEs, with an adjusted hazard ratio of 1.57 (95% confidence interval, 1.10-2.24; P=0.013), independently of age, sex, ethnicity, body mass index, diabetes mellitus, and hypertension. CONCLUSIONS: OSA is independently associated with subsequent MACCEs in patients undergoing percutaneous coronary intervention. Evaluation of therapeutic approaches to mitigate OSA-associated risk is warranted. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01306526.

The influence of timing of polysomnography on diagnosis of obstructive sleep apnea in patients presenting with acute myocardial infarction and stable coronary artery disease.

BACKGROUND: We aimed to determine if timing of polysomnography (PSG) influences the diagnosis of obstructive sleep apnea (OSA) in acute myocardial infarction (AMI) or stable coronary artery disease (CAD). METHODS: A total of 160 patients admitted with AMI or stable CAD were consecutively recruited for either in-hospital (n=80) or postdischarge (n=80) PSG. RESULTS: The median time from admission to PSG for the in-hospital and postdischarge groups was 1 day and 17 days, respectively (P<.001). Overall, 59 patients (36.9%) were diagnosed with OSA (apnea-hypopnea index [AHI] > or = 15), and they were more likely to have diabetes mellitus (DM), hypertension, hyperlipidemia, chronic renal failure, and a greater body mass index (BMI) (P<.05 for all). The diagnosis of OSA was significantly higher (P=.037) in patients who had a PSG performed as an inpatient than those who had a PSG as an outpatient. There was a significant interaction between clinical presentation and the effect of PSG timing on the diagnosis of OSA (P=.003). For the patients presenting with AMI but not those with stable CAD, in-hospital PSG was an independent predictor of OSA (adjusted odds ratio, 3.84 [95% confidence interval, 1.42-10.41]; P=.008). CONCLUSION: The timing of PSG influenced the diagnosis of OSA in patients who presented with AMI but not in those who presented with stable CAD.

Relationship between apnoea-hypopnoea index and angiographiccoronary disease phenotypes in patients presenting with acutemyocardial infarction.

BACKGROUND: Relationship between obstructive sleep apnoea and atherosclerosis has not been confirmed using coronary angiography. We sought to investigate the relationships between the apnoea-hypopnoea index (AHI) and angiographic coronary disease phenotypes.
 METHODS: SYNTAX score, lesion complexity, and thrombus burden grade were determined in 125 patients presenting with acute myocardial infarction and had undergone a screening sleep study. Severe OSA was defined as AHI ≥ 30.
 RESULTS: Most of the recruited patients were male (97.6%). Severe obstructive sleep apnoea was diagnosed in 37% of the patients. The severe obstructive sleep apnoea group (n = 46) was older (P = 0.039) and more obese (P = 0.003) than the non-severe group (n = 79). There was no evidence of difference between the severe and non-severe obstructive sleep apnoea groups with regard to SYNTAX score (P = 0.871), number of complex lesions (P = 0.241), and thrombus burden grade (P = 0.433). Multivariate analysis adjusting for difference in age and body mass index did not change the findings. CONCLUSION: Using the three angiographic scoring systems, we found no association between AHI and angiographic coronary disease phenotypes, suggesting a limited effect of obstructive sleep apnoea on the amount and distribution of coronary plaques in patients presenting with acute myocardial infarction.

Myocardial infarction in singapore: ethnic variation in evidence-based therapy and its association with socioeconomic status, social network size and perceived stress level.

BACKGROUND: Singapore is a multiethnic Asian country comprising predominantly Chinese, Malays, and Indians. We sought to study the disparities in evidence-based therapy for people from these three ethnic groups who were admitted to hospital with ST-segment elevation myocardial infarction (STEMI). We also examined its association with socioeconomic level and social network size and the influence on psychological stress level. METHODS: In a prospective study, patients admitted with STEMI were recruited for a questionnaire survey. Relevant demographic and clinical data were collected. RESULTS: A total of 364 patients were recruited and categorised based on ethnicity: Chinese (222 patients), Malays (72 patients), and Indians (70 patients). Malays and Indians were significantly younger than Chinese at the time of presentation with STEMI. Malays had significantly more children than the Chinese and Indians. Malays were in the lowest socioeconomic class, based on education level (P ≤ .02) and residential type (P ≤ .003). Most (87%) patients were treated with primary percutaneous coronary intervention. There were no significant differences between Chinese, Malays, and Indians in accessibility to primary percutaneous coronary intervention, symptom-to-balloon time, door-to-balloon time, and prescription of evidence-based medications. Malays had larger social networks for information support (P ≤ .05) and financial support (P ≤ .04) than Chinese and Indians. There were no significant differences between the three ethnic groups in satisfaction with social support. The perceived stress level was higher among Malays and Indians than Chinese. CONCLUSIONS: Although Malays were underprivileged in the socioeconomic level, no significant difference in healthcare disparities were observed among the three ethnic groups. This may be a reflection of the advancement in Singapore's healthcare system. The lower socioeconomic level may also explain the higher perceived stress level in Malays.