Use of a new high-sensitivity assay for cardiac troponin T to stratify the risk of cardiovascular disease in outpatients with type-2 diabetes

Background: Chronic elevation of cardiac troponin T (TnT) levels as measured by conventional assays is strongly associated with structural heart disease and cardiovascular events. A new high-sensitivity assay for TnT makes it possible to measure concentrations more than a factor of 5 lower than the limits of detection of conventional assays. We evaluated the utility of serum TnT as a risk marker of cardiovascular disease in 409 outpatients with type-2 diabetes mellitus (T2DM). Results: TnT was detectable (>0. 002 ng/mL) in 80% of patients, and elevation in TnT levels (>0. 014 ng/mL) was found in 19. 3%, suggesting a higher prevalence of structural heart diseases in T2DM patients. A history of cardiovascular disease was noted in 89 (22%) patients. Patients with diabetic microvascular complications and those with abnormal electrocardiogram including left ventricular hypertrophy had higher TnT levels. Patients with increased levels of TnT (>0. 014 ng/mL) were older, had higher values of N-terminal pro-B-type natriuretic peptide (NT-proBNP), C-reactive protein, cystatin C, and urinary albumin/creatinine ratio, had lower values of hemoglobin and estimated glomerular filtration rate, and had a higher prevalence of cardiovascular disease compared with those without increased TnT levels. In stepwise logistic analysis, NT-proBNP (odds ratio 7. 40 per 10-fold increase, P < 0. 0001) and cystatin C (18. 0 per 1. 0 mg/L, P < 0. 0001) were independently associated with elevation of TnT levels. HsTnT level, cystatin C, and HDL-cholesterol were also independent risk factors for history of major cardiovascular diseases in T2DM patients. Conclusion: This new high-sensitivity TnT assay may be useful for stratifying cardiovascular risk in outpatients with T2DM.