Low admission LDL-cholesterol is associated with increased 3-year all-cause mortality in patients with non ST segment elevation myocardial infarction

Background: The relationship between admission low-density lipoprotein (LDL) levels and long-term outcomes has not been established in patients with acute coronary syndrome. We tested the hypothesis that patients who develop non-ST segment elevation myocardial infarction (NSTEMI) despite low LDL have a worse cardiovascular outcome in the long term. Methods: Patients admitted with NSTEMI between 1 January 1997 and 31 December 2000 and with fasting lipid profiles measured within 24 hours of admission were selected for analysis. Baseline characteristics and 3-year all-cause mortality were compared between the patients with LDL above and below the median. Multivariate analysis was used to determine the predictors of all-cause mortality, and adjusted survival was analyzed using the Cox proportional hazard model. Results: Of the total of 517 patients, 264 had LDL £ 105 mg/dL and 253 had LDL > 105 mg/dL. There was no difference in age, gender, severity of coronary artery disease, and left ventricular ejection fraction between the 2 groups. Thirty-six percent of patients with LDL £ 105 mg/dL and 24% of patients with LDL > 105 mg/dL were on lipid-lowering therapy on admission. After 3 years, patients with admission LDL £ 105 mg/dL had higher all-cause mortality rate compared to patients with LDL > 105 mg/dL (14.8% vs. 7.1%, p = 0.005). The higher all-cause mortality persisted (OR 1.8, 95% CI 1.0–3.5, p = 0.05) even after adjustment for confounding variables. Conclusions: In our cohort, lower LDL-cholesterol at admission was associated with decreased 3-year survival in patients with NSTEMI. Whether this was a result of current therapy or a marker for worse baseline characteristics needs to be studied further

Systematic review and meta-analysis of mortality and digoxin use in atrial fibrillation

Background: There is growing controversy regarding the association between digoxin and mortality in atrial fibrillation (AF). The aim of this analysis was to systematically review digoxin use and risk of mortality in patients with AF. Methods: MEDLINE, EMBASE, GoogleScholar, CINAHL, meeting abstracts, presentations, and Cochrane central databases were searched from inception through December 2014, without language restrictions. For a study to be selected, it had to report the risk of mortality associated with digoxin use in AF patients as an outcome measure. Data were extracted by 2 independent authors. Evidence tables were created. Results: A total of 16 studies (6 post hoc analyses of randomized controlled trials) with 111,978 digoxin users and 389,643 non-digoxin users were included. In a random effects model, patients treated with digoxin had a 27% increased risk of all-cause mortality (pooled HR 1.27; 95% CI 1.19–1.36) and 21% increased risk of cardiovascular mortality (pooled HR 1.21; 95% CI 1.12–1.30) compared with those who did not use digoxin. In a random effects model, the association of digoxin with all-cause mortality was stronger for AF patients without heart failure (pooled HR 1.47; 95% CI 1.25–1.73) than AF patients with heart failure (pooled HR 1.21; 95% CI 1.07–1.36, interaction p = 0.06). Conclusions: Digoxin use in AF is associated with increased risk of all-cause and cardiovascular mortalities. The effect size was larger for AF patients without heart failure than AF patients with heart failure. The study suggests further directed analyses to study the effect that is suggested by this meta-analysis, especially in AF without heart failure.

Low admission triglyceride and mortality in acute coronary syndrome patients

Background: The relationship between admission triglyceride (TG) levels and long-term outcomes has not been established in patients with acute coronary syndrome. We tested the hypothesis that patients who develop non-ST segment elevation myocardial infarction (NSTEMI) despite low TG have a worse cardiovascular outcome in the long term. Methods: Patients admitted with NSTEMI between 1 January 1997 and 31 December 2000 and with fasting lipid profiles measured within 24 hours of admission were included for analysis. Baseline characteristics and three-year all-cause mortality were compared between the patients with TG above and below the median. Multivariate analysis was used to determine the predictors of all-cause mortality and adjusted survival was analyzed using the Cox proportional hazard model. Results: Of 517 patients, 395 had TG £ 200 mg/dL and 124 had TG > 200 mg/dL. Patients with low TG were more often Caucasian, with no significant differences in gender or severity of coronary artery disease between the two groups. There was a trend for increased all-cause mortality at six months (9% vs 3%, p = 0.045) and three years (13.4% vs 5.6%, p = 0.016) in patients with low TG. In multivariate analysis, low TG level at admission was an independent predictor of increased mortality at three years (adjusted OR 2.5, 95% CI = 1.04–5.9, p = 0.04). Conclusions: In our cohort, lower TG at admission is associated with increased three-year mortality in patients with NSTEMI. Whether this is a result of current therapy, or a marker for worse baseline characteristics, needs to be studied further. (Cardiol J 2011; 18, 3: 297–303

Predicting diabetes mellitus using SMOTE and ensemble machine learning approach: The Henry Ford ExercIse Testing (FIT) project

Machine learning is becoming a popular and important approach in the field of medical research. In this study, we investigate the relative performance of various machine learning methods such as Decision Tree, Naïve Bayes, Logistic Regression, Logistic Model Tree and Random Forests for predicting incident diabetes using medical records of cardiorespiratory fitness. In addition, we apply different techniques to uncover potential predictors of diabetes. This FIT project study used data of 32,555 patients who are free of any known coronary artery disease or heart failure who underwent clinician-referred exercise treadmill stress testing at Henry Ford Health Systems between 1991 and 2009 and had a complete 5-year follow-up. At the completion of the fifth year, 5,099 of those patients have developed diabetes. The dataset contained 62 attributes classified into four categories: demographic characteristics, disease history, medication use history, and stress test vital signs. We developed an Ensembling-based predictive model using 13 attributes that were selected based on their clinical importance, Multiple Linear Regression, and Information Gain Ranking methods. The negative effect of the imbalance class of the constructed model was handled by Synthetic Minority Oversampling Technique (SMOTE). The overall performance of the predictive model classifier was improved by the Ensemble machine learning approach using the Vote method with three Decision Trees (Naïve Bayes Tree, Random Forest, and Logistic Model Tree) and achieved high accuracy of prediction (AUC = 0.92). The study shows the potential of ensembling and SMOTE approaches for predicting incident diabetes using cardiorespiratory fitness data

Chronotropic incompetence and long-term risk of heart failure: The henry ford exercise testing project

Background: Chronotropic incompetence (CI) has been associated with cardiovascular mortality. However, its relationship with long-term risk of heart failure (HF) is not well studied. Methods: We included 43,098 participants (mean age 51.7±12.3 years, 47.5% females, 66.6% white) of the FIT project who completed a clinically indicated exercise test between 1991 and 2009. Patients with coronary artery disease, prior HF or on heart rate reducing medications were excluded. Incident HF was defined by having a documented diagnosis in 3 separate clinical encounters. CI was defined by inability to achieve 85% of maximal age predicted heart rate (calculated by 220 - age) with exercise. Multivariable adjusted Cox models were used to assess the independent association of CI with incident HF. Results: At baseline, 5,249 (12.2%) had CI. After a mean follow-up duration of 10.9 ± 4.6 years, 1329 (3.2%) experienced new onset HF. The cumulative incidence of HF was 397 (7.6%) among CI patients compared with 992 (2.6%) among chronotropic competent patients. Figure 1 shows the cumulative incidence of heart failure by CI status. In multivariable Cox regression models, CI was associated with increased risk of incident heart failure (HR 1.73; 95% CI 1.48 – 2.03, p \u3c0.001) after adjusting for confounders. There were no interactions by age, sex, race, body mass index. Conclusions: Our study shows that CI is an independent risk factor for HF. Further research is needed to determine whether CI could be a therapeutic target for HF

A systematic review of internet-based worksite wellness approaches for cardiovascular disease risk management: outcomes, challenges & opportunities.

ContextThe internet is gaining popularity as a means of delivering employee-based cardiovascular (CV) wellness interventions though little is known about the cardiovascular health outcomes of these programs. In this review, we examined the effectiveness of internet-based employee cardiovascular wellness and prevention programs.Evidence acquisitionWe conducted a systematic review by searching PubMed, Web of Science and Cochrane library for all published studies on internet-based programs aimed at improving CV health among employees up to November 2012. We grouped the outcomes according to the American Heart Association (AHA) indicators of cardiovascular wellbeing--weight, BP, lipids, smoking, physical activity, diet, and blood glucose.Evidence synthesisA total of 18 randomized trials and 11 follow-up studies met our inclusion/exclusion criteria. Follow-up duration ranged from 6-24 months. There were significant differences in intervention types and number of components in each intervention. Modest improvements were observed in more than half of the studies with weight related outcomes while no improvement was seen in virtually all the studies with physical activity outcome. In general, internet-based programs were more successful if the interventions also included some physical contact and environmental modification, and if they were targeted at specific disease entities such as hypertension. Only a few of the studies were conducted in persons at-risk for CVD, none in blue-collar workers or low-income earners.ConclusionInternet based programs hold promise for improving the cardiovascular wellness among employees however much work is required to fully understand its utility and long term impact especially in special/at-risk populations

The association of clinical indication for exercise stress testing with all-cause mortality: the FIT Project

INTRODUCTION: We hypothesized that the indication for stress testing provided by the referring physician would be an independent predictor of all-cause mortality. MATERIAL AND METHODS: We studied 48,914 patients from The Henry Ford Exercise Testing Project (The FIT Project) without known congestive heart failure who were referred for a clinical treadmill stress test and followed for 11 ±4.7 years. The reason for stress test referral was abstracted from the clinical test order, and should be considered the primary concerning symptom or indication as stated by the ordering clinician. Hierarchical multivariable Cox proportional hazards regression was performed, after controlling for potential confounders including demographics, risk factors, and medication use as well as additional adjustment for exercise capacity in the final model. RESULTS: A total of 67% of the patients were referred for chest pain, 12% for shortness of breath (SOB), 4% for palpitations, 3% for pre-operative evaluation, 6% for abnormal prior testing, and 7% for risk factors only. There were 6,211 total deaths during follow-up. Compared to chest pain, those referred for palpitations (HR = 0.72, 95% CI: 0.60-0.86) and risk factors only (HR = 0.72, 95% CI: 0.63-0.82) had a lower risk of all-cause mortality, whereas those referred for SOB (HR = 1.15, 95% CI: 1.07-1.23) and pre-operative evaluation (HR = 2.11, 95% CI: 1.94-2.30) had an increased risk. In subgroup analysis, referral for palpitations was protective only in those without coronary artery disease (CAD) (HR = 0.75, 95% CI: 0.62-0.90), while SOB increased mortality risk only in those with established CAD (HR = 1.25, 95% CI: 1.10-1.44). CONCLUSIONS: The indication for stress testing is an independent predictor of mortality, showing an interaction with CAD status. Importantly, SOB may be associated with higher mortality risk than chest pain, particularly in patients with CAD