Risk stratification in unstable coronary artery disease: Exercise test and troponin T from a gender perspective

Abstract

OBJECTIVESThe study was done to determine the prognostic yield of an early symptom-limited exercise test (ET) and measurement of troponin T (TnT) in men and women with unstable coronary artery disease (CAD), with special reference to gender differences.BACKGROUNDEarly risk assessment is essential for the application of appropriate treatment and further management in patients with unstable CAD. The early symptom-limited ET together with specific biochemical marker determination is an inexpensive, widely applicable method for early risk stratification. In women, however, the ET is considered less reliable, and there are few data on biochemical markers for risk stratification in women.METHODSIn a substudy of the Fragmin during InStability in Coronary artery disease (FRISC I) trial, 395 women and 778 men with unstable CAD who performed an early ET were followed for six months. Blood samples for TnT determination were taken in 342 women and 621 men at inclusion.RESULTSBased on the ET results, low-, intermediate-, and high-risk response groups were identified with event rates of cardiac death or myocardial infarction (MI) of 1%, 9%, and 19%, respectively, among women and 8%, 14%, and 20%, respectively, among men. Patients who could not perform the ET had an event rate similar to the high-risk group. The TnT levels were divided into three groups: <0.06, 0.06–0.19, and ≥0.20 μg/liter with event rates of 1%, 10%, and 18%, respectively, among women and 9%, 14%, and 18%, respectively, among men. Combining the ET results with TnT levels identified a low-risk group with an event rate of 3% in the male population and no events in the female population.CONCLUSIONSDirect comparison between men and women from the same population with a high pretest likelihood of disease suggests that both TnT and the early symptom-limited ET are at least as useful as prognostic risk indicators in women as they are in men.