The intersection of heart failure and cancer in women: a review.

Cancer and cardiovascular disease represent the two leading causes of morbidity and mortality worldwide. Women continue to enjoy a greater life expectancy than men. However, this comes at a cost with more women developing diabetes, hypertension and coronary artery disease as they age. These traditional cardiovascular risk factors not only increase their lifetime risk of heart failure but also their overall risk of cancer. In addition to this, many of the cancers with female preponderance are treated with potentially cardiotoxic therapies, adding to their increased risk of developing heart failure. As a result, we are faced with a higher risk population, potentially suffering from both cancer and heart failure simultaneously. This is of particular concern given the coexistence of heart failure and cancer can confer a worse prognosis than either a single diagnosis of heart failure or cancer alone. This review article explores the intersection of heart failure and cancer in women at multiple levels, including traditional cardiovascular risk factors, cardiovascular toxicity derived from antineoplastic and radiation therapy, shared pathophysiology and HF as an oncogenic process. This article further identifies opportunities and strategies for intervention and optimisation, whilst highlighting the need for contemporary guidelines to better inform clinical practice.

Obstructive sleep apnea and temporal changes in cardiac repolarization in patients undergoing coronary artery bypass grafting.

STUDY OBJECTIVES: In coronary artery bypass grafting (CABG), abnormal cardiac repolarization is associated with adverse cardiovascular events that can be measured via the QTc interval. We investigated the impact of obstructive sleep apnea on the change in repolarization after CABG and the association of change in repolarization with the occurrence of major adverse cardiac and cerebrovascular events. METHODS: A total of 1,007 patients from 4 hospitals underwent an overnight sleep study prior to a nonemergent CABG. Electrocardiograms of 954 patients (median age: 62 years; male: 86%; mean follow-up: 2.1 years) were acquired prospectively within 48 hours before CABG (T1) and within 24 hours after CABG (T2). QTc intervals were measured using the BRAVO algorithm by Analyzing Medical Parameters for Solutions LLC. The change in T2 from T1 for QTc (ΔQTc) was derived, and Cox regression was performed. RESULTS: Compared with those without, patients who developed major adverse cardiac and cerebrovascular events (n = 115) were older and had (1) a higher prevalence of smoking, hypertension, diabetes mellitus, and chronic kidney disease; (2) a higher apnea-hypopnea index and oxygen desaturation index; and (3) a smaller ΔQTc. Cox regression analysis demonstrated a smaller ΔQTc to be an independent risk factor for major adverse cardiac and cerebrovascular events (hazard ratio: 0.997; P = .032). In the multivariable regression model, a higher oxygen desaturation index was independently associated with a smaller ΔQTc (correlation coefficient: -0.58; P < .001). CONCLUSIONS: A higher preoperative oxygen desaturation index was an independent predictor of a smaller ΔQTc. ΔQTc within 24 hours after CABG could be a novel predictor of occurrence of major adverse cardiac and cerebrovascular events at medium-term follow-up. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: Undiagnosed Sleep Apnea and Bypass OperaTion (SABOT); URL: https://classic.clinicaltrials.gov/ct2/show/NCT02701504; Identifier: NCT02701504. CITATION: Teo YH, Yong CL, Ou YH, et al. Obstructive sleep apnea and temporal changes in cardiac repolarization in patients undergoing coronary artery bypass grafting. J Clin Sleep Med. 2024;20(1):49-55.

Non-Vitamin K Antagonist Oral Anticoagulants versus Low Molecular Weight Heparin for Cancer-Related Venous Thromboembolic Events: Individual Patient Data Meta-Analysis.

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality in cancer patients. Low molecular weight heparin (LMWH) has been the standard of care but new guidelines have approved the use of non-vitamin K antagonist oral anticoagulants (NOAC). By conducting an individual patient data (IPD) meta-analysis of randomised controlled trials (RCTs) comparing the outcomes of NOAC versus LMWH in cancer patients, we aim to determine an ideal strategy for the prophylaxis of VTE and prevention of VTE recurrence. Three databases were searched from inception until 19 October 2022. IPD was reconstructed from Kaplan-Meier curves. Shared frailty, stratified Cox and Royston-Parmar models were fit to compare the outcomes of venous thromboembolism recurrence and major bleeding. For studies without Kaplan-Meier curves, aggregate data meta-analysis was conducted using random-effects models. Eleven RCTs involving 4844 patients were included. Aggregate data meta-analysis showed that administering NOACs led to a significantly lower risk of recurrent VTE (RR = 0.65; 95%CI: 0.50-0.84) and deep vein thrombosis (DVT) (RR = 0.60; 95%CI: 0.40-0.90). In the IPD meta-analysis, NOAC when compared with LMWH has an HR of 0.65 (95%CI: 0.49-0.86) for VTE recurrence. Stratified Cox and Royston-Parmar models demonstrated similar results. In reducing risks of recurrent VTE and DVT among cancer patients, NOACs are superior to LMWHs without increased major bleeding.

Global Registry of Acute Coronary Events Score Underestimates Post-Acute Coronary Syndrome Mortality among Cancer Patients.

Background Patients with prior cancer are at increased risk of acute coronary syndrome (ACS) with poorer post-ACS outcomes. We aimed to ascertain if the Global Registry of Acute Coronary Events (GRACE) score accurately predicts mortality risk among patients with ACS and prior cancer. Methods We linked nationwide ACS and cancer registries from 2007 to 2018 in Singapore. A total of 24,529 eligible patients had in-hospital and 1-year all-cause mortality risk calculated using the GRACE score (2471 prior cancer; 22,058 no cancer). Results Patients with prior cancer had two-fold higher all-cause mortality compared to patients without cancer (in-hospital: 22.8% versus 10.3%, p < 0.001; 1-year: 49.0% vs. 18.7%, p < 0.001). Cardiovascular mortality did not differ between groups (in-hospital: 5.2% vs. 4.8%, p = 0.346; 1-year: 6.9% vs. 6.1%, p = 0.12). The area under the receiver operating characteristic curve of the GRACE score for prediction of all-cause mortality was less for prior cancer (in-hospital: 0.64 vs. 0.80, p < 0.001; 1-year: 0.66 vs. 0.83, p < 0.001). Among patients with prior cancer and a high-risk GRACE score > 140, in-hospital revascularization was not associated with lower cardiovascular mortality than without in-hospital revascularization (6.7% vs. 7.6%, p = 0.50). Conclusions The GRACE score performs poorly in risk stratification of patients with prior cancer and ACS.

Rationale and Design of the Cessation Of Pharmacotherapy In Recovered Chemotherapy-induced cardioToxicity (COP-RCT): A Pilot Study.

BACKGROUND: Cancer therapeutics-related cardiac dysfunction (CTRCD) is a well-recognised complication of cancer treatment. Treatment of CTRCD involves cardioprotective therapy (CPT) which can lead to a recovery of CTRCD with normalisation of the left ventricular ejection fraction (LVEF). As a result, there are potentially millions of cancer survivors with recovered CTRCD on CPT. Cardioprotective therapy can be associated with an undesirable long-term pill burden, financial costs, and side effects. Cancer survivorship is anticipated to increase significantly by the end of this decade. To date, there is no evidence of the safety of stopping CPT in this setting. This study seeks to evaluate the hypothesis that ceasing cardioprotective medication is a feasible and safe option without significant impact on LVEF in low-risk patients who have recovered from CTRCD. METHODS AND ANALYSIS: We will perform a multicentre prospective open-label randomised controlled trial with blinded endpoint (PROBE) of supervised CPT cessation compared to continuing CPT (control). The primary study end point is the change in LVEF by cardiac magnetic resonance imaging at 6 months of enrolment between the two groups. Secondary end points include changes in quality-of-life questionnaires, other cardiac imaging parameters, and recurrence of heart failure. CONCLUSION: Cessation Of Pharmacotherapy In Recovered Chemotherapy-induced cardioToxicity (COP-RCT) is one of the first studies currently underway to evaluate the safety of ceasing CPT in recovered CTRCD. The results will inform clinical practice in this evidence-free zone.

Comparing Renin-Angiotensin-Aldosterone Blockade Regimens for Long-Term Chemotherapy-Related Cardiac Dysfunction: A Network Meta-Analysis.

PURPOSE: Cancer therapies including trastuzumab and anthracyclines are cardiotoxic and cause cardiac dysfunction. To prevent cardiotoxicity, pharmacological agents used in heart failure have been administered concomitantly with cardiotoxic cancer therapy, but few studies to date have performed a head-to-head comparison of these different agents. This systematic review and network meta-analysis of randomized-controlled trials aims to evaluate the efficacy of renin-angiotensin-aldosterone system (RAAS) blockers, namely angiotensin-converting enzyme inhibitors (ACE-Is), aldosterone receptor blockers (ARBs), and mineralocorticoid receptor antagonists (MRAs), in primary prevention against chemotherapy-related cardiac dysfunction in patients receiving anthracyclines and/or trastuzumab. METHODS: A systematic search was performed in major web databases for studies from inception to 15 September 2022. A Bayesian network meta-analysis model was used to assess the relative effects of competing treatments on the primary outcomes of risk of significant decline in left ventricular ejection fraction (LVEF) and mean LVEF decline. Secondary outcomes included left ventricular diastolic function, global longitudinal strain, and cardiac biomarkers. This study is registered with PROSPERO, CRD42022357980. RESULTS AND CONCLUSION: Nineteen studies reported the effects of 13 interventions (N = 1905 patients). Only enalapril (RR 0.05, 95% CI 0.00-0.20) was associated with reduced risk of patients developing significant decline in LVEF relative to placebo. Subgroup analysis showed that the beneficial effect of enalapril was driven by protection against anthracycline-associated toxicity. In addition, no RAAS-inhibiting agents showed efficacy in protection against treatment with both anthracycline and trastuzumab. The use of RAAS inhibition therapy did not conclusively impact on other markers of cardiac function, including left ventricular diastolic function and cardiac biomarkers.

Natural Progression of Left Ventricular Function following Anthracyclines without Cardioprotective Therapy: A Systematic Review and Meta-Analysis.

BACKGROUND: Anthracyclines form the backbone of many systemic chemotherapy regimens but are accompanied by dose-limiting cardiotoxicity. We elucidate the progression and severity of cardiac function over time, in the absence of cardioprotection, which less is known about. METHODS: This PRISMA-guideline-adherent review was registered on PROSPERO (CRD42022373496). RESULTS: 26 studies met the eligibility criteria including a total of 910 patients. The overall reduction in post-anthracycline pooled mean left ventricular ejection fraction (LVEF) in placebo arms of the included randomised-controlled trials was 4.5% (95% CI, 2.6 to 6.4). The trend in LVEF showed a progressive decline until approximately 180 days, after which there was no significant change. Those receiving a cumulative anthracycline dose of 300 mg/m2 experienced a more profound reduction. The overall pooled risk of a 10% absolute decline in LVEF from baseline, or a decline to an LVEF below 50%, was 17% (95% CI: 11 to 24; I2 = 71%). Sensitivity analyses of baseline LVEF and trastuzumab treatment status did not yield significant differences. CONCLUSION: While the mean LVEF decline in patients without cardioprotective therapy was clinically small, a vulnerable subset experienced significant impairment. Further research to best identify those who benefit most from cardioprotective therapies when receiving anthracyclines is required.

Prior Cancer Is Associated with Lower Atherosclerotic Cardiovascular Disease Risk at First Acute Myocardial Infarction.

Background: Patients with cancer are at increased risk of acute myocardial infarction (AMI). It is unclear if the Atherosclerotic Cardiovascular Disease (ASCVD) risk score at incident AMI is reflective of this higher risk in patients with prior cancer than those without. Methods: We linked nationwide AMI and cancer registries from 2008 to 2019. A total of 18,200 eligible patients with ASCVD risk score calculated at incident AMI were identified (1086 prior cancer; 17,114 no cancer). Results: At incident AMI, age-standardized mean ASCVD risk was lower in the prior cancer group (18.6%) than no cancer group (20.9%) (p < 0.001). Prior to incident AMI, smoking, hypertension, hyperlipidemia and diabetes mellitus were better controlled in the prior cancer group. However post-AMI, prior cancer was associated with lower guideline-directed medical therapy usage and higher all-cause mortality (adjusted hazard ratio 1.85, 95% confidence interval 1.66−2.07). Conclusions: AMI occurred despite better control of cardiovascular risk factors and lower age-standardized estimated mean 10-year ASCVD risk among patients with prior cancer than no cancer. Prior cancer was associated with lower guideline-directed medical therapy post-AMI and higher mortality.

Lipid profiles and outcomes of patients with prior cancer and subsequent myocardial infarction or stroke.

Patients with cancer are at increased risk of myocardial infarction (MI) and stroke. Guidelines do not address lipid profile targets for these patients. Within the lipid profiles, we hypothesized that patients with cancer develop MI or stroke at lower low density lipoprotein cholesterol (LDL-C) concentrations than patients without cancer and suffer worse outcomes. We linked nationwide longitudinal MI, stroke and cancer registries from years 2007-2017. We identified 42,148 eligible patients with MI (2421 prior cancer; 39,727 no cancer) and 43,888 eligible patients with stroke (3152 prior cancer; 40,738 no cancer). Median LDL-C concentration was lower in the prior cancer group than the no cancer group at incident MI [2.43 versus 3.10 mmol/L, adjusted ratio 0.87 (95% CI 0.85-0.89)] and stroke [2.81 versus 3.22 mmol/L, adjusted ratio 0.93, 95% CI 0.91-0.95)]. Similarly, median triglyceride and total cholesterol concentrations were lower in the prior cancer group, with no difference in high density lipoprotein cholesterol. Prior cancer was associated with higher post-MI mortality [adjusted hazard ratio (HR) 1.48, 95% CI 1.37-1.59] and post-stroke mortality (adjusted HR 1.95, 95% CI 1.52-2.52). Despite lower LDL-C concentrations, patients with prior cancer had worse post-MI and stroke mortality than patients without cancer.

Sleep apnea and recurrent heart failure hospitalizations after coronary artery bypass grafting.

STUDY OBJECTIVES: Sleep apnea is prevalent in patients undergoing coronary artery bypass grafting (CABG). We investigated the relationship between sleep apnea and recurrent heart failure hospitalizations in patients undergoing nonurgent CABG. METHODS: Between November 2013 and December 2018, 1,007 patients completed a sleep study prior to CABG and were followed up until April 2020. Recurrent heart failure hospitalizations were analyzed by Poisson, negative binomial, Andersen-Gill, and joint frailty models, with partial and full adjustment for covariates. RESULTS: At an average follow-up of 3.3 years, the number of patients with 0, 1, or ≥ 2 heart failure hospitalizations were 908 (90.2%), 62 (6.2%), and 37 (3.7%), respectively. The total number of heart failure hospitalizations was 179, comprising 62 (35%) first and 117 (65%) repeat events. The numbers of heart failure hospitalizations for the sleep apnea (n = 513, 50.9%) and nonsleep apnea groups were 127 and 52, respectively. Negative binomial regression demonstrated that sleep apnea was associated with recurrent heart failure hospitalizations (fully adjusted rate ratio, 1.71; 95% confidence interval [CI], 1.12-2.62; P = .013). Similar results were found in Poisson (1.63; 95% CI, 1.15-2.31; P = .006), Andersen-Gill (1.66; 95% CI, 1.01-2.75; P = .047), and joint frailty models (1.72; 95% CI, 1.00-3.01; P = .056). CONCLUSIONS: In patients after CABG, repeat events accounted for two-thirds of heart failure hospitalizations. Sleep apnea was independently associated with recurrent heart failure hospitalizations. CITATION: Teo YH, Tam WT, Koo C-Y, et al. Sleep apnea and recurrent heart failure hospitalizations after coronary artery bypass grafting. J Clin Sleep Med. 2021;17(12):2399-2407.

Recurrent Stent Thrombosis Secondary to Immunoglobulin G4-Related Disease.

Immunoglobulin G4-related disease (IgG4-RD) is an insidiously progressive multiorgan disease. However, lack of familiarity with IgG4-RD results in patients often being undiagnosed and undertreated. IgG4-RD can affect any organ, and manifests as aortitis within the cardiovascular system. Cardiac involvement is less common, and myocardial infarction is rarely reported. We report the first case of a patient with multiple myocardial infarctions caused by recurrent stent thrombosis associated with IgG4-RD, which resolved upon treatment of IgG4-RD. This case highlights the importance for cardiologists to consider IgG4-RD as a rare but possible association with stent thrombosis.

Chemotherapy and adverse cardiovascular events in colorectal cancer patients undergoing surgical resection.

BACKGROUND: Colorectal cancer patients undergoing surgical resection are at increased short-term risk of post-operative adverse events. However, specific predictors for long-term major adverse cardiac and cerebrovascular events (MACCE) are unclear. We hypothesised that patients who receive chemotherapy are at higher risk of MACCE than those who did not. METHODS: In this retrospective study, 412 patients who underwent surgical resection for newly diagnosed colorectal cancer from January 2013 to April 2015 were grouped according to chemotherapy status. MACCE was defined as a composite of cardiovascular death, myocardial infarction, stroke, unplanned revascularisation, hospitalisation for heart failure or angina. Predictors of MACCE were identified using competing risks regression, with non-cardiovascular death a competing risk. RESULTS: There were 200 patients in the chemotherapy group and 212 patients in the non-chemotherapy group. The overall prevalence of prior cardiovascular disease was 20.9%. Over a median follow-up duration of 5.1 years from diagnosis, the incidence of MACCE was 13.3%. Diabetes mellitus and prior cardiovascular disease were associated with an increased risk of MACCE (subdistribution hazard ratio, 2.56; 95% CI, 1.48-4.42) and 2.38 (95% CI, 1.36-4.18) respectively. The chemotherapy group was associated with a lower risk of MACCE (subdistribution hazard ratio, 0.37; 95% CI, 0.19-0.75) compared to the non-chemotherapy group. CONCLUSIONS: Amongst colorectal cancer patients undergoing surgical resection, there was a high incidence of MACCE. Diabetes mellitus and prior cardiovascular disease were associated with an increased risk of MACCE. Chemotherapy was associated with a lower risk of MACCE, but further research is required to clarify this association.

Sleep apnea and diabetes mellitus are independently associated with cardiovascular events and hospitalization for heart failure after coronary artery bypass grafting.

The relative and combined effects of sleep apnea with diabetes mellitus (DM) on cardiovascular outcomes in patients undergoing coronary artery bypass grafting (CABG) remain unknown. In this secondary analysis of data from the SABOT study, 1007 patients were reclassified into four groups based on their sleep apnea and DM statuses, yielding 295, 218, 278, and 216 patients in the sleep apnea (+) DM (+), sleep apnea (+) DM (-), sleep apnea (-) DM (+), and sleep apnea (-) DM (-) groups, respectively. After a mean follow-up period of 2.1 years, the crude incidence of major adverse cardiac and cerebrovascular event was 18% in the sleep apnea (+) DM (+), 11% in the sleep apnea (+) DM (-), 13% in the sleep apnea (-) DM (+), and 5% in the sleep apnea (-) DM (-) groups. Using sleep apnea (-) DM (-) as the reference group, a Cox regression analysis indicated that sleep apnea (+) and DM (+) independently predicted MACCEs (adjusted hazard ratio, 3.2; 95% confidence interval, 1.7-6.2; p = 0.005) and hospitalization for heart failure (adjusted hazard ratio, 12.6; 95% confidence interval, 3.0-52.3; p < 0.001). Sleep apnea and DM have independent effects on the prognosis of patients undergoing CABG.Clinical trial registration: ClinicalTrials.gov identification no. NCT02701504.

Sleep apnoea and cardiovascular outcomes after coronary artery bypass grafting.

OBJECTIVE: Patients with advanced coronary artery disease are referred for coronary artery bypass grafting (CABG) and it remains unknown if sleep apnoea is a risk marker. We evaluated the association between sleep apnoea and major adverse cardiac and cerebrovascular events (MACCE) in patients undergoing non-emergent CABG. METHODS: This was a prospective cohort study conducted between November 2013 and December 2018. Patients from four public hospitals referred to a tertiary cardiac centre for non-emergent CABG were recruited for an overnight sleep study using a wrist-worn Watch-PAT 200 device prior to CABG. RESULTS: Among the 1007 patients who completed the study, sleep apnoea (defined as apnoea-hypopnoea index ≥15 events per hour) was diagnosed in 513 patients (50.9%). Over a mean follow-up period of 2.1 years, 124 patients experienced the four-component MACCE (2-year cumulative incidence estimate, 11.3%). There was a total of 33 cardiac deaths (2.5%), 42 non-fatal myocardial infarctions (3.7%), 50 non-fatal strokes (4.9%) and 36 unplanned revascularisations (3.2%). The crude incidence of MACCE was higher in the sleep apnoea group than the non-sleep apnoea group (2-year estimate, 14.7% vs 7.8%; p=0.002). Sleep apnoea predicted the incidence of MACCE in unadjusted Cox regression analysis (HR 1.69; 95% CI 1.18 to 2.43), and remained statistically significant (adjusted HR 1.57; 95% CI 1.09 to 2.25), after adjustment for age, sex, body mass index, left ventricular ejection fraction, diabetes mellitus, hypertension, chronic kidney disease and excessive daytime sleepiness. CONCLUSION: Sleep apnoea is independently associated with increased MACCE in patients undergoing CABG. TRIAL REGISTRATION NUMBER: NCT02701504.

Screening and treatment of obstructive sleep apnea in acute coronary syndrome. A randomized clinical trial.

BACKGROUND: We evaluated the effects of sleep-study guided multidisciplinary therapy (SGMT) of obstructive sleep apnoea (OSA) in patients presenting with acute coronary syndrome. METHODS: Eligible patients were randomized into (1) SGMT, comprised a sleep study during the index admission and continuous positive airway pressure and behavioral therapy for those with at least mild OSA or (2) standard therapy. The primary end point was the change in the plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) level from baseline to the 7-month follow-up. RESULTS: A total of 159 patients completed the trial. Of the 70 patients randomized to SGMT, 21 (30%), 15 (22%) and 27 (39%) were diagnosed with mild, moderate and severe OSA, respectively. Continuous positive airway pressure and a positional pillow were prescribed to 57 (91%) and 6 (9%) patients with OSA. Although plasma NT-proBNP levels were lower after 7 months compared to the baseline, the levels did not differ significantly between the SGMT and standard therapy groups at baseline (579 ±â€¯1117 vs. 611 ±â€¯899 pg/dL, p = .851) or at 7 months (90 ±â€¯167 vs. 93 ±â€¯174 pg/dL, p = .996). The changes in NT-proBNP levels from baseline to 7 months were similar with SGMT and standard therapy (-489 vs. -518 pg/dL, p = .726). Similar findings were observed for the plasma ST2 and hs-CRP levels. CONCLUSIONS: OSA screening and multifaceted treatment during the sub-acute phase of acute coronary syndrome did not further reduce the levels of cardiovascular biomarkers when compared with standard therapy. CLINICAL TRIAL REGISTRATION: clinicaltrial.gov NCT02599298.

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.

Optimal Body Mass Index Cut-offs for Identification of Patients with Coronary Artery Disease at High Risk of Obstructive Sleep Apnoea.

BACKGROUND: We sought to evaluate the relationship between Body Mass Index (BMI) and obstructive sleep apnoea (OSA) in Chinese patients hospitalised with coronary artery disease, and to determine the optimal BMI cut-off for prediction of OSA. METHODS: Consecutive Chinese patients who were hospitalised with symptomatic coronary artery disease were recruited to undergo an in-hospital sleep study. RESULTS: A total of 587 patients were recruited. Using cut-off for Asians, 81.2% of the cohort was overweight (BMI ≥23kg/m(2)) and 31.6% was obese (≥27kg/m(2)). A total of 59.5% was diagnosed with OSA, defined as apnoea-hypopnoea index ≥15. Body mass index, hypertension and smoking were predictors of OSA. Multiple logistic regression analysis showed that BMI remains an independent predictor of OSA (odds ratio: 1.11 [95% confidence interval: 1.06 to 1.17], p<0.001) after adjusting for smoking and hypertension. Further analysis using BMI and Apnoea-Hypopnoea Index (AHI) as continuous variables showed significant correlation between BMI and AHI (Pearson's r =0.25, P<0.001). In adjusted models, optimal BMI cut-offs to screen for OSA were 27.3kg/m(2), 23.0-23.9kg/m(2), and 20kg/m(2) for patients with neither, either, or both predictors (smoking and hypertension) respectively. The area under the curve for the adjusted and unadjusted models were similar (0.6013 vs 0.6262, p=0.118). CONCLUSIONS: Body mass index represents a convenient and readily available tool for bedside identification of patients at high risk of OSA. Body mass index cut-offs to predict risks of OSA in Chinese patients with symptomatic coronary artery disease are defined in this study.

A meta-analysis of the predictive accuracy of postoperative mortality using the American Society of Anesthesiologists' physical status classification system.

BACKGROUND: The American Society of Anesthesiologists' physical status (ASA) tool has been applied to determine compensation, risk adjustment and risk prediction, but little is known about the accuracy and generalizability of this tool for prediction of postoperative mortality. METHODS: We systematically investigated prior published reports of associations between ASA physical status and mortality to test the hypothesis that ASA physical status will have varying accuracy in prediction of postoperative mortality across surgical populations with varying surgical risk of mortality. We used random effects models and metaregression to account for heterogeneity. RESULTS: Combining 77 studies with 165,705 patients, the ASA physical status tool demonstrated the following pooled performance (95 % confidence intervals)--sensitivity 0.74 (0.73, 0.74), specificity 0.67 (0.67, 0.67), and area under summary receiver operating curve 0.736 (0.725, 0.747). Metaregression revealed that study death rates and surgical specialty were significant factors. CONCLUSION: ASA physical status is a better predictor of postoperative mortality in settings with lower rather than higher death rates.

Prognostic implication of obstructive sleep apnea diagnosed by post-discharge sleep study in patients presenting with acute coronary syndrome.

OBJECTIVE: We aimed to determine the prognostic implications of obstructive sleep apnea (OSA) diagnosed during the recovery phase of acute coronary syndrome (ACS). METHODS: Patients presenting with ACS and treated with percutaneous coronary intervention were recruited prospectively for a home-based sleep study within 30 days of hospital discharge. Major adverse cardiac and cerebrovascular events (MACCEs) assessed included cardiac death, myocardial infarction, stroke, unplanned revascularization, and hospitalization for heart failure. RESULTS: Of the 85 patients recruited, 68 successfully completed the study. The median time from percutaneous coronary intervention to sleep study was 14 days (interquartile range: 7.5-27 days). OSA was diagnosed in 24 patients (35.3%) (apnea-hypopnea index > or =15). A drug-eluting stent was implanted into the target lesion in 45 patients (66.2%). None of the study patients had received treatment for OSA. At 24-month follow-up, the MACCE incidence was 34.9% in the OSA group and 5.1% in the non-OSA group (P=0.008, log-rank test). After adjusting for the possible confounding effect of age, gender, coronary intervention indications, hypertension, smoking, and body mass index, OSA remained an independent predictor of MACCEs (adjusted hazard ratio, 6.95; 95% confidence interval, 1.17-41.4; P=0.033). CONCLUSION: OSA diagnosed in patients treated with percutaneous coronary intervention for ACS by post-discharge sleep studies conducted 2 weeks after percutaneous coronary intervention was independently associated with MACCEs at 24-month follow-up.