This study evaluates and compares the performance of different machine learning techniques on predicting the individuals at risk of developing hypertension, and who are likely to benefit most from ...interventions, using the cardiorespiratory fitness data. The dataset of this study contains information of 23,095 patients who underwent clinician- referred exercise treadmill stress testing at Henry Ford Health Systems between 1991 and 2009 and had a complete 10-year follow-up. The variables of the dataset include information on vital signs, diagnosis and clinical laboratory measurements. Six machine learning techniques were investigated: LogitBoost (LB), Bayesian Network classifier (BN), Locally Weighted Naive Bayes (LWB), Artificial Neural Network (ANN), Support Vector Machine (SVM) and Random Tree Forest (RTF). Using different validation methods, the RTF model has shown the best performance (AUC = 0.93) and outperformed all other machine learning techniques examined in this study. The results have also shown that it is critical to carefully explore and evaluate the performance of the machine learning models using various model evaluation methods as the prediction accuracy can significantly differ.
Coronary Calcium Score and Cardiovascular Risk Greenland, Philip; Blaha, Michael J.; Budoff, Matthew J. ...
Journal of the American College of Cardiology,
07/2018, Volume:
72, Issue:
4
Journal Article
Peer reviewed
Open access
Coronary artery calcium (CAC) is a highly specific feature of coronary atherosclerosis. On the basis of single-center and multicenter clinical and population-based studies with short-term and ...long-term outcomes data (up to 15-year follow-up), CAC scoring has emerged as a widely available, consistent, and reproducible means of assessing risk for major cardiovascular outcomes, especially useful in asymptomatic people for planning primary prevention interventions such as statins and aspirin. CAC testing in asymptomatic populations is cost effective across a broad range of baseline risk. This review summarizes evidence concerning CAC, including its pathobiology, modalities for detection, predictive role, use in prediction scoring algorithms, CAC progression, evidence that CAC changes the clinical approach to the patient and patient behavior, novel applications of CAC, future directions in scoring CAC scans, and new CAC guidelines.
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To inform the study and regulation of emerging tobacco products, we sought to identify sensitive biomarkers of tobacco-induced subclinical cardiovascular damage by testing the cross-sectional ...associations of smoking with 17 biomarkers of inflammation in 2,702 GENOA study participants belonging to sibships ascertained on the basis of hypertension. Cigarette smoking was assessed by status, intensity (number of cigarettes per day), burden (pack-years of smoking), and time since quitting. We modeled biomarkers as geometric mean (GM) ratios using generalized estimating equations (GEE). The mean age of participants was 61 ±10 years; 64.5% were women and 54.4% African American. The prevalence of smoking was 12.2%. After adjusting for potential confounders, 6 of 17 biomarkers were significantly higher among current smokers at a Bonferroni adjusted p-value threshold (p<0.003). High sensitivity C-reactive protein was the most elevated biomarker among current smokers when compared to never smokers GM ratio = 1.39 (95% CI: 1.23, 1.57); p <0.001. Among former smokers, each pack-year of cigarettes smoked was associated with a 0.4% higher serum level of hsCRP GM ratio = 1.004 (95% CI: 1.001, 1.006); p = 0.002 and each 5-year lapsed since quitting was associated with a 4% lower serum level of hsCRP GM ratio = 0.96 (95% CI: 0.93, 0.99); p = 0.006. However, we found no significant association of smoking intensity or burden with biomarkers of inflammation among current smokers. HsCRP appears to be the most sensitive biomarker of inflammation associated with cigarette smoking of those investigated, and could be a useful biomarker of smoking-related injury for the study and regulation of emerging tobacco products.
Abstract Objective To evaluate the effect of statins on short-term cognitive function and the long-term incidence of dementia. Patients and Methods A systematic search was performed of MEDLINE, ...EMBASE, and the Cochrane Central Register from their inception to April 25, 2013. Adults with no history of cognitive dysfunction treated with statins were included from high-quality randomized controlled trials and prospective cohort studies after formal bias assessment. Results Sixteen studies were included in qualitative synthesis and 11 in quantitative synthesis. Short-term trials did not show a consistent effect of statin therapy on cognitive end points. Digit Symbol Substitution Testing (a well-validated measure of cognitive function) was the most common short-term end point, with no significant differences in the mean change from baseline to follow-up between the statin and placebo groups (mean change, 1.65; 95% CI, –0.03 to 3.32; 296 total exposures in 3 trials). Long-term cognition studies included 23,443 patients with a mean exposure duration of 3 to 24.9 years. Three studies found no association between statin use and incident dementia, and 5 found a favorable effect. Pooled results revealed a 29% reduction in incident dementia in statin-treated patients (hazard ratio, 0.71; 95% CI, 0.61-0.82). Conclusion In patients without baseline cognitive dysfunction, short-term data are most compatible with no adverse effect of statins on cognition, and long-term data may support a beneficial role for statins in the prevention of dementia.
Abstract Background The improvement in discrimination gained by adding nontraditional cardiovascular risk markers cited in the 2013 American College of Cardiology/American Heart Association ...cholesterol guidelines to the atherosclerotic cardiovascular disease (ASCVD) risk estimator (pooled cohort equation PCE) is untested. Objectives This study assessed the predictive accuracy and improvement in reclassification gained by the addition of the coronary artery calcium (CAC) score, the ankle–brachial index (ABI), high-sensitivity C-reactive protein (hsCRP) levels, and family history (FH) of ASCVD to the PCE in participants of MESA (Multi-Ethnic Study of Atherosclerosis). Methods The PCE was calibrated (cPCE) and used for this analysis. The Cox proportional hazards survival model, Harrell’s C statistics, and net reclassification improvement analyses were used. ASCVD was defined as myocardial infarction, coronary heart disease–related death, or fatal or nonfatal stroke. Results Of 6,814 MESA participants not prescribed statins at baseline, 5,185 had complete data and were included in this analysis. Their mean age was 61 years; 53.1% were women, 9.8% had diabetes, and 13.6% were current smokers. After 10 years of follow-up, 320 (6.2%) ASCVD events occurred. CAC score, ABI, and FH were independent predictors of ASCVD events in the multivariable Cox models. CAC score modestly improved the Harrell’s C statistic (0.74 vs. 0.76; p = 0.04); ABI, hsCRP levels, and FH produced no improvement in Harrell’s C statistic when added to the cPCE. Conclusions CAC score, ABI, and FH were independent predictors of ASCVD events. CAC score modestly improved the discriminative ability of the cPCE compared with other nontraditional risk markers.
Accurate risk assessment of atherosclerotic cardiovascular disease (ASCVD) is essential to effectively balance the risks and benefits of therapy for primary prevention.
To compare the calibration and ...discrimination of the new American Heart Association (AHA) and American College of Cardiology (ACC) ASCVD risk score with alternative risk scores and to explore preventive therapy as a cause of the reported risk overestimation using the AHA-ACC-ASCVD score.
Prospective epidemiologic study of ASCVD.
MESA (Multi-Ethnic Study of Atherosclerosis), a community-based, sex-balanced, multiethnic cohort.
4227 MESA participants aged 50 to 74 years and without diabetes at baseline.
Observed and expected events for the AHA-ACC-ASCVD score were compared with 4 commonly used risk scores-and their respective end points-in MESA after a 10.2-year follow-up.
The new AHA-ACC-ASCVD and 3 older Framingham-based risk scores overestimated cardiovascular events by 37% to 154% in men and 8% to 67% in women. Overestimation was noted throughout the continuum of risk. In contrast, the Reynolds Risk Score overestimated risk by 9% in men but underestimated risk by 21% in women. Aspirin, lipid-lowering or antihypertensive therapy, and interim revascularization did not explain the overestimation.
Comparability of MESA with target populations for primary prevention and possibility of missed events in MESA.
Of the 5 risk scores, 4, including the new AHA-ACC-ASCVD score, showed overestimation of risk (25% to 115%) in a modern, multiethnic cohort without baseline clinical ASCVD. If validated, overestimation of ASCVD risk may have substantial implications for individual patients and the health care system.
National Heart, Lung, and Blood Institute.
Abstract This expert consensus statement summarizes the available data regarding the prognostic value of CAC in the asymptomatic population and its ability to refine individual risk prediction, ...addresses the limitations identified in the current traditional risk factor-based treatment strategies recommended by the 2013 ACC/AHA Prevention guidelines including use of the Pooled Cohort Equations (PCE), and the US Preventive Services Task Force (USPSTF) Recommendation Statement for Statin Use for the Primary Prevention of Cardiovascular Disease in Adults. It provides CAC based treatment recommendations both within the context of the shared decision making model espoused by the 2013 ACC/AHA Prevention guidelines and independent of these guidelines.
Summary Background The JUPITER trial showed that some patients with LDL-cholesterol concentrations less than 3·37 mmol/L (<130 mg/dL) and high-sensitivity C-reactive protein (hsCRP) concentrations of ...2 mg/L or more benefit from treatment with rosuvastatin, although absolute rates of cardiovascular events were low. In a population eligible for JUPITER, we established whether coronary artery calcium (CAC) might further stratify risk; additionally we compared hsCRP with CAC for risk prediction across the range of low and high hsCRP values. Methods 950 participants from the Multi-Ethnic Study of Atheroslcerosis (MESA) met all criteria for JUPITER entry. We compared coronary heart disease and cardiovascular disease event rates and multivariable-adjusted hazard ratios after stratifying by burden of CAC (scores of 0, 1–100, or >100). We calculated 5-year number needed to treat (NNT) by applying the benefit recorded in JUPITER to the event rates within each CAC strata. Findings Median follow-up was 5·8 years (IQR 5·7–5·9). 444 (47%) patients in the MESA JUPITER population had CAC scores of 0 and, in this group, rates of coronary heart disease events were 0·8 per 1000 person-years. 74% of all coronary events were in the 239 (25%) of participants with CAC scores of more than 100 (20·2 per 1000 person-years). For coronary heart disease, the predicted 5-year NNT was 549 for CAC score 0, 94 for scores 1–100, and 24 for scores greater than 100. For cardiovascular disease, the NNT was 124, 54, and 19. In the total study population, presence of CAC was associated with a hazard ratio of 4·29 (95% CI 1·99–9·25) for coronary heart disease, and of 2·57 (1·48–4·48) for cardiovascular disease. hsCRP was not associated with either disease after multivariable adjustment. Interpretation CAC seems to further stratify risk in patients eligible for JUPITER, and could be used to target subgroups of patients who are expected to derive the most, and the least, absolute benefit from statin treatment. Focusing of treatment on the subset of individuals with measurable atherosclerosis could allow for more appropriate allocation of resources. Funding National Institutes of Health–National Heart, Lung, and Blood Institute.
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