Troponin and Cardiac Events in Stable Ischemic Heart Disease and Diabetes

Abstract

BACKGROUND Cardiac troponin concentrations are used to identify patients who would benefit from urgent revascularization for acute coronary syndromes. We hypothesized that they might be used in patients with stable ischemic heart disease to identify those at high risk for cardiovascular events who might also benefit from prompt coronary revascularization. METHODS We measured the cardiac troponin T concentration at baseline with a high-sensitivity assay in 2285 patients who had both type 2 diabetes and stable ischemic heart disease and were enrolled in the Bypass Angioplasty Revascularization Investigation in Type 2 Diabetes trial. We tested for an association between the troponin T concentration and a composite end point of death from cardiovascular causes, myocardial infarction, or stroke; we then evaluated whether random assignment to prompt revascularization reduced the rate of the composite end point in patients with an abnormal troponin T concentration (≥14 ng per liter) as compared with those with a normal troponin T concentration (<14 ng per liter). RESULTS Of the 2285 patients, 2277 (99.6%) had detectable (≥3 ng per liter) troponin T concentrations and 897 (39.3%) had abnormal troponin T concentrations at baseline. The 5-year rate of the composite end point was 27.1% among the patients who had had abnormal troponin T concentrations at baseline, as compared with 12.9% among those who had had normal baseline troponin T concentrations. In models that were adjusted for cardiovascular risk factors, severity of diabetes, electrocardiographic abnormalities, and coronary anatomy, the hazard ratio for the composite end point among patients with abnormal troponin T concentrations was 1.85 (95% confidence interval [CI], 1.48 to 2.32; P<0.001). Among patients with abnormal troponin T concentrations, random assignment to prompt revascularization, as compared with medical therapy alone, did not result in a significant reduction in the rate of the composite end point (hazard ratio, 0.96; 95% CI, 0.74 to 1.25). CONCLUSIONS The cardiac troponin T concentration was an independent predictor of death from cardiovascular causes, myocardial infarction, or stroke in patients who had both type 2 diabetes and stable ischemic heart disease. An abnormal troponin T value of 14 ng per liter or higher did not identify a subgroup of patients who benefited from random assignment to prompt coronary revascularization. (Funded by the National Institutes of Health and Roche Diagnostics; BARI 2D ClinicalTrials.gov number, NCT00006305.)

Randomized Trial of the Effects of Insulin and Metformin on Myocardial Injury and Stress in Diabetes Mellitus: A Post Hoc Exploratory Analysis

“…Higher proportions have been reported in other cohorts (eg, 39% in the BARI 2D [Bypass Angioplasty Revascularization Investigation 2 Diabetes] trial) 10. In patients with diabetes mellitus with and without established cardiovascular disease, cardiac troponin concentrations are a significant predictor of myocardial infarction, stroke, heart failure, and cardiovascular death 9, 10, 23, 24. As a result, there is considerable interest in identifying treatment strategies that might modify troponin concentrations and thus confer cardiovascular benefit.…”

“…As a result, there is considerable interest in identifying treatment strategies that might modify troponin concentrations and thus confer cardiovascular benefit. Our data suggest that glucose control with either insulin glargine, metformin, or the combination, at least over the relatively short‐term follow‐up of this trial, might be added to the list of interventions (including coronary revascularization and statin therapy) that do not appear to lead to clinically meaningful reductions in troponin concentrations 10, 25…”

“…Our conclusions on the effects of glucose control on circulating concentrations of hsTnT and NT‐proBNP are limited by the relatively short duration of the trial. A more‐sustained effort at glucose control might lead to improvements in hsTnT that were not observed within 12 weeks, although no changes were noted in the BARI 2D or LIPID (Long‐Term Intervention with Pravastatin in Ischaemic Disease) studies after 1 year of follow‐up 10, 25. We did not collect measures of renal function, urine microalbumin, New York Heart Association class, or a history of hypoglycemic episodes.…”

“…Although a reduction in cardiovascular morbidity and mortality has been a major goal of therapy in patients with T2DM, therapeutic strategies focused on intensive glycemic control in these patients have largely failed to show a substantial impact on cardiovascular morbidity and mortality, at least in the short term 5, 6, 7, 8. Circulating concentrations of cardiac troponin, a marker of myocardial injury, and natriuretic peptides (NPs), markers of myocardial stress, have emerged as powerful predictors of cardiovascular risk in stable patients with and without T2DM 9, 10, 11, 12, 13. Both markers have also been associated with abnormalities in glucose metabolism.…”

Prognostic impact of cardiac troponin T in patients with stable coronary artery disease and diabetes

“…Recently, Everett et al 7. reported that using Bypass Angiography Revascularization Investigation in Type 2 Diabetes trial data, the cardiac troponin T concentration is an independent predictor of death from cardiovascular causes, myocardial infraction or stroke in patients who had both type 2 diabetes and stable ischemic heart disease.…”