ABSTRACT
To determine the potential of a non-invasive acoustic device (CADScor®System) to reclassify patients with intermediate pre-test probability (PTP) and clinically suspected stable coronary artery disease (CAD) into a low probability group thereby ruling out significant CAD. Audio recordings and clinical data from three studies were collected in a single database. In all studies, patients with a coronary CT angiography indicating CAD were referred to coronary angiography. Audio recordings of heart sounds were processed to construct a CAD-score. PTP was calculated using the updated Diamond-Forrester score and patients were classified according to the current ESC guidelines for stable CAD: low < 15%, intermediate 15-85% and high > 85% PTP. Intermediate PTP patients were re-classified to low probability if the CAD-score was ≤ 20. Of 2245 patients, 212 (9.4%) had significant CAD confirmed by coronary angiography ( ≥ 50% diameter stenosis). The average CAD-score was higher in patients with significant CAD (38.4 ± 13.9) compared to the remaining patients (25.1 ± 13.8; p < 0.001). The reclassification increased the proportion of low PTP patients from 13.6% to 41.8%, reducing the proportion of intermediate PTP patients from 83.4% to 55.2%. Before reclassification 7 (3.1%) low PTP patients had CAD, whereas post-reclassification this number increased to 28 (4.0%) (p = 0.52). The net reclassification index was 0.209. Utilization of a low-cost acoustic device in patients with intermediate PTP could potentially reduce the number of patients referred for further testing, without a significant increase in the false negative rate, and thus improve the cost-effectiveness for patients with suspected stable CAD.
Subject(s)
Coronary Artery Disease/diagnosis , Coronary Stenosis/diagnosis , Heart Sounds , Phonocardiography , Adult , Aged , Aged, 80 and over , Algorithms , Coronary Angiography , Coronary Artery Disease/classification , Coronary Artery Disease/economics , Coronary Artery Disease/physiopathology , Coronary Stenosis/classification , Coronary Stenosis/economics , Coronary Stenosis/physiopathology , Cost Savings , Cost-Benefit Analysis , Decision Support Techniques , Female , Health Care Costs , Humans , Male , Middle Aged , Phonocardiography/economics , Phonocardiography/instrumentation , Predictive Value of Tests , Prognosis , Reproducibility of Results , Retrospective Studies , Severity of Illness Index , Young AdultABSTRACT
Glutathione-S-transferase T1 (GSTT1) and GSTM1 detoxify carcinogens and thus potentially contribute to inter-individual susceptibility to cancer. We determined the ability of GST copy number variation (CNV) to predict the risk of cancer in the general population. Exact copy numbers of GSTT1 and GSTM1 were measured by real-time PCR in 10 247 individuals, of whom 2090 had cancer. In men, the cumulative incidence of prostate cancer increased and the cumulative 5-year survival decreased with decreasing GSTT1 copy numbers (trends=0.02). The hazard ratios (HRs) (95% CIs) for prostate cancer and for death after prostate cancer diagnosis were, respectively, 1.2 (0.8-1.8) and 1.2 (0.6-2.1) for GSTT1*1/0, and 1.8 (1.1-3.0) and 2.2 (1.1-4.4) for GSTT1*0/0 versus GSTT1*1/1. In women, the cumulative incidence of corpus uteri cancer increased with decreasing GSTT1 copy numbers (trend=0.04). The HRs for corpus uteri cancer were, respectively, 1.8 (1.0-3.2) and 2.2 (1.0-4.6) for GSTT1*1/0 and GSTT1*0/0 versus GSTT1*1/1. Finally, the cumulative incidence of bladder cancer increased, and the cumulative 5-year survival decreased, with decreasing GSTM1 copy numbers (P=0.03-0.05). The HRs for bladder cancer were, respectively, 1.5 (0.7-3.2) and 2.0 (0.9-4.3) for GSTM1*1/0 and GSTM1*0/0 versus GSTM1*1/1. The HR for death after bladder cancer diagnosis was 1.9 (1.0-3.7) for GSTM1*0/0 versus GSTM1*1/0. In conclusion, exact CNV in GSTT1 and GSTM1 predict incidence and 5-year survival from prostate and bladder cancer, and incidence of corpus uteri cancer.