Abstract 16021: Contemporary Temporal Trends in Acute Coronary Syndrome in the Community by Age and Gender From 2008-2011: The Kaiser Permanente ACS Study
Background: Limited data exist about the most recent population trends in the incidence of acute coronary syndrome (ACS) in the community and whether they vary by age and gender.
Methods: We identified all ACS patients >=18 years old diagnosed between 2008 and 2011 within Kaiser Permanente Northern California, a large integrated health care delivery system carrying for ~3.3 million persons in northern California. Hospitalized ACS was defined as acute myocardial infarction (MI) (ICD-9 code 410.x) or unstable angina (ICD-9 code 411.x) with an elevated cardiac troponin I. Incidence per 100,000 person-years (p-y) was calculated overall for ACS, and for ST-segment elevation MI (STEMI) and non[[Unable to Display Character: –]]ST-segment elevation MI (NSTEMI) in the overall population and stratified by age group (18-49, 50-64, 65-74, 75-84 and >=85 years) and gender. Trends in events per calendar year were examined using Poisson regression.
Results: Rates (per 100,000 p-y) declined between 2008-2011 for ACS (233 to 201), NSTEMI (187 to 159) and STEMI (46 to 42) (P< 0.01 for all linear trends). ACS rates from 2008-2011 were significantly higher for men than women, but rates for both genders declined over the study period (304 to 266 and 168 to 143 events per 100,000 p-y for men and women, respectively; P<0.01 for both). The majority of ACS event rate reduction over the study period occurred primarily in older patients (269 to 220, 582 to 473, 1035 to 827, and 1705 to 1310 events per 100,000 p-y for patients 50-64, 65-74, 75-84, and >=85 years, respectively; P<0.01 for linear trends). However, there was no statistically significant reduction in the ACS event rate for patients <50 years (36 to 33 events per 100,000 p-y from 2008-2011; P= 0.11).
Conclusions: In a large, diverse community-based population, ACS incidence declined from 2008-2011. Although the absolute ACS rate was higher for men than women, favorable trends were observed in both genders. The majority of the reduction in ACS over time in this population was due to fewer NSTEMI events and was concentrated primarily in older patients (>=50 years). Future research should identify predictors of events in younger at-risk patients to help improve outcomes in this clinically vulnerable population.
- © 2013 by American Heart Association, Inc.