Abstract 19205: Most Hospitalized Patients With Elevated Cardiac Troponin Levels Die From Non Cardiac Causes

Abstract

Cardiac troponins (Tn) have major prognostic importance as bio-markers in acute coronary syndromes (ACS). However during hospitalizations, Tn levels are often assayed in patients who do not have an acute coronary syndrome. To examine the prognostic implications of elevated Tn levels in patients with and without cardiovascular disease, survival at 12 months among 251,944 patients admitted in the period 2006-8 to public hospitals in NSW, Australia, was linked to measured troponin levels and their ICD-109 diagnostic code. In total 171,253 patients (68%) had a cardiovascular ICD code (CVD100-199) and 80,691 (32%) had a non-CVD code. Troponin positivity was defined as ≥ 1X the upper reference limit (URL) for the troponin T or I assay used at each institution. In total, of troponin positive patients at 12 months, 3,120 (33%) who had a CVD code had died whereas 6,205 (67%) of patients with a non CVD code had died. The hazard ratios for mortality among patients who were ‘troponin positivity’ and had non-CVD codes, adjusted for age and gender, were 2.0 [1.09-2.01] and for CVD codes 100-199 was 2.5 [2.3-2.7]. Among troponin positive patients with non-CVD admission diagnoses, the three most frequent causes of death at 12 months were: 1) diseases of the respiratory system, and 2) neoplasia, and 3) injury, poisoning and or external causes. In conclusion, among a large cohort of patients admitted over a two year period to public hospitals in NSW, Australia, more troponin positive patients with a non-CVD ICD code died at 12 months than those with an CVD code for their admission. Non cardiac disease is a common cause of elevated troponin levels and it has significant adverse prognostic consequences.