Table 1

Baseline characteristics of patients with acute coronary syndrome stratified by cardiac troponin I concentration at 4 months

Total CDCSBiomarker cohort≤5 ng/L6 ng/L–99th centile>99th centile
n21401776795815166
Age, years66.5 (12.3)66.4 (12.0)63.7 (11.4)68.2 (11.9)70.8 (12.9)
Sex, male1531 (71.5)1282 (72.2)534 (67.2)661 (81.1)87 (52.4)
Past medical history*
 Hypertension1104 (52.0)905 (51.4)365 (46.4)432 (53.5)108 (65.1)
 Hypercholesterolaemia1135 (54.3)952 (54.5)440 (56.1)426 (53.2)86 (53.1)
 Diabetes mellitus353 (16.5)276 (15.6)96 (12.1)142 (17.4)38 (22.9)
 Smoking status
 Never smoked787 (36.8)669 (37.7)290 (36.5)316 (38.8)63 (38.0)
 Ex-smoker1218 (56.9)999 (56.2)448 (56.4)465 (57.1)86 (51.8)
 Current smoker135 (6.3)108 (6.1)57 (7.2)34 (4.2)17 (10.2)
 Prior myocardial infarction635 (29.9)504 (28.5)168 (21.2)268 (33.0)68 (41.5)
 Prior stroke257 (12.1)200 (11.3)66 (8.3)103 (12.7)31 (18.7)
 Prior congestive heart failure201 (9.4)154 (8.7)27 (3.4)95 (11.7)32 (19.5)
Status at presentation
 Heart rate, bpm73.1 (20.3)72.7 (20.6)70.7 (19.3)73.0 (20.8)81.2 (23.2)
 Systolic blood pressure, mm Hg134.9 (20.3)135.3 (20.6)135.1 (20.0)133.4 (21.2)148.3 (20.3)
 Killip class
 I1577 (73.8)1329 (75.0)664 (83.7)569 (69.9)96 (57.8)
 II526 (24.6)419 (23.6)124 (15.6)233 (28.6)62 (37.3)
 III/IV33 (1.5)25 (1.4)5 (0.6)12 (1.5)8 (4.8)
 eGFR, mL/min65.6 (19.9)66.1 (19.5)71.5 (16.9)62.9 (20.1)55.5 (20.5)
 ST depression471 (22.1)386 (21.9)112 (14.1)218 (26.9)56 (33.9)
Positive cardiac biomarker (index admission)1740 (81.4)1422 (80.1)575 (72.3)691 (84.9)156 (94.0)
No. of diseased vessels†
 0105 (6.4)90 (6.5)63 (9.4)21 (3.4)6 (5.8)
 1450 (27.5)387 (27.8)206 (30.7)155 (25.0)26 (25.2)
 2487 (29.7)413 (29.6)194 (29.0)187 (30.2)32 (31.1)
 3596 (36.4)503 (36.1)207 (30.9)257 (41.5)39 (37.9)
In-hospital percutaneous coronary intervention1080 (50.5)932 (52.5)442 (55.6)427 (52.4)63 (38.0)
LVEF at 4 months, %59.0 (52.0, 65.0)61.0 (56.0, 66.0)58.0 (49.0, 64.0)51.0 (40.0, 61.0)
Medications at discharge
 Aspirin2087 (97.6)1736 (97.9)781 (98.4)798 (98.0)157 (94.6)
 Clopidogrel1244 (58.2)1053 (59.4)489 (61.6)479 (58.8)85 (51.2)
 Renin-angiotensin system-blocking agents‡1334 (62.4)1095 (61.7)419 (52.8)553 (67.9)123 (74.1)
 Beta-blocker1856 (86.7)1554 (87.5)706 (88.8)710 (87.1)138 (83.1)
 Statin1948 (91.1)1623 (91.5)743 (93.6)739 (90.8)141 (84.9)
Optimal medical therapy at discharge¶884 (49.8)411 (51.7)406 (49.8)67 (40.4)
Index diagnosis
 Unstable angina567 (26.5)495 (27.9)294 (37.0)177 (21.7)24 (14.5)
 NSTEMI1089 (50.9)864 (48.6)377 (47.4)388 (47.6)99 (59.6)
 STEMI484 (22.6)417 (23.5)124 (15.6)250 (30.7)43 (25.9)
Time from index admission to 4-month visit, days128.0 (116.0, 140.0)128.0 (116.0, 140.0)129.0 (117.0, 142.0)126.0 (115.0, 138.0)128.0 (117.0, 141.8)
GRACE score111.0 (31.7)109.9 (30.8)99.4 (25.2)116.2 (30.9)129.9 (36.2)
GRACE score tertile¶
 Low614 (30.6)517 (31.0)286 (38.1)204 (26.6)27 (17.8)
 Intermediate675 (33.7)588 (35.2)311 (41.5)240 (31.2)37 (24.3)
 High716 (35.7)565 (33.8)153 (20.4)324 (42.2)88 (57.9)
  • *See https://www.outcomes-umassmed.org/grace/grace_risk_table.aspx).

  • †Determined at time of index hospital admission.

  • ‡Determines from diagnostic coronary angiography performed during index admission.

  • §Including ACE inhibitors or angiotensin receptor blockers.

  • ¶GRACE score tertiles determined according to index diagnosis: NSTEACS, low<88, intermediate 89–118, high≥119; STEMI, low<99, intermediate 100–127, high≥128.

  • §Optimal medical therapy defined as a prescription for all of aspirin, clopidogrel and a statin. In addition, prescription of a beta-blocker was required if the LVEF was ≤40%. An ACE inhibitor or angiotensin receptor blocker was also required if the LVEF was ≤40% or the patient had a diagnosis of hypertension or diabetes mellitus.

  • CDCS, Coronary Disease Cohort Study; eGFR, estimated glomerular filtration rate; GRACE, Global Registry of Acute Coronary Events; LVEF, left ventricular ejection fraction; NSTEMI, non-ST-segment elevation myocardial infarction; STEMI, ST-segment elevation myocardial infarction.