Abstract 12514: The Difference in Risk of Future Cardiovascular Events for Patients Presenting With Acute Coronary Syndrome Diminishes After 6 Months Compared to Non-Acute Coronary Syndrome Patients: The Intermountain Heart Collaborative Study
Background: Pts presenting with acute coronary syndrome (ACS) are at an increased risk of future events. However, at what point in time, if at all, this difference in risk becomes that of non-ACS pts is not well-known.
Methods: A total of 32,591 (ACS: 16,756 [51.4%]; non-ACS: 15,835 [48.6%]) pts undergoing coronary angiography for CAD determination were studied. Landmark analyses were performed at 0-30, 31-180, 181-365, and 366-1825 days for MACE (death, MI, HF hospitalization, CVA). To be included, pts needed to be event-free at the start of follow-up. Cox hazard regression was performed to determine hazard ratios between ACS and non-ACS pts.
Results: Age for ACS (63±13) and non-ACS (63±12) pts was similar (p=0.66); more ACS pts were male (69% vs. 64%, p<0.0001). ACS pts had a significantly increased frequency of MACE at 30 days (10.9% [1829/16,735] vs. 4.6% [727/15,822], p<0.0001) and 31-180 days (7.3% [1020/13,932] vs. 5.1% [723/14,174], p<0.0001) post-angiography. However, this difference in MACE among ACS and non-ACS pts became similar after 6 months (3.2% [398/14,417] vs. 3.4% [442/12,994], p=0.38) and 1 year (17.8% [2069/11,648] vs. 18.4% [2241/12,179], p=0.20), with a trend toward a decreasing risk after multivariable adjustment (HR=0.93, p=0.02). See Figure.
Conclusions: ACS pts are at an increased risk of MACE within the first 6 months following angiography compared to non-ACS pts. However, this risk diminishes after 6 months and then can be considered stable at the rate for chronic CAD.
Figure. Multivariable Cox hazard regression plots and hazard ratios (HR) between ACS and non-ACS patients at A) 0-30 days, B) 31-180 days, C) 181-365 days, and D) 366-1825 days for the occurrence of MACE (death, MI, HF hospitalization, CVA).
Author Disclosures: T.L. Bair: None. H.T. May: None. V. Le: None. B.D. Horne: None. J.L. Anderson: None. D.L. Lappé: None. J.B. Muhlestein: None.
- © 2014 by American Heart Association, Inc.