The prevalence and outcomes of in-hospital acute myocardial infarction in the Department of Veterans Affairs Health System.
BACKGROUND
Most studies of the epidemiology and treatment of acute myocardial infarction (AMI) have focused on patients who experienced onset of their symptoms in the community and then presented to the hospital. There are, however, patients whose symptoms of AMI begin after hospitalization for other medical conditions. The purposes of this study were to determine the prevalence of in-hospital AMI in the Veterans Health Administration (VHA) and to compare baseline characteristics, treatments, and outcomes according to whether individuals presented with AMI or had an in-hospital AMI.


METHODS
This was a retrospective cohort study of 7054 veterans who were hospitalized for AMI in 127 VHA medical centers between July 2003 and August 2004. The main outcome measure was 30-day mortality. Key covariates included age, body mass index, admission systolic blood pressure, heart rate, previous use of lipid-lowering drugs, elevated admission troponin value, prolonged and/or atypical chest pain on admission, and ST-segment elevation on the initial electrocardiogram.


RESULTS
There were 792 patients (11.2%) who had AMI while hospitalized for other medical conditions. These patients differed substantially from those who presented to the hospital with AMI. The odds of 30-day mortality were greater in the in-hospital group (odds ratio, 3.6; 95% confidence interval, 3.1-4.3; P<.001) and remained higher after statistical adjustment (odds ratio, 2.0; 95% confidence interval, 1.7-2.4; P<.001).


CONCLUSIONS
Although most attention has been paid to patients with AMI admitted via the community emergency medical system or through the emergency department, AMI occurring during hospitalization for other medical problems is an important clinical problem.
Maynard
Charles
C
Health Services Research and Development, VA Puget Sound Health Care System, Seattle, WA 98101, USA. cmaynard@u.washington.edu
Lowy
Elliott
E
Rumsfeld
John
J
Sales
Ann E
AE
Sun
Haili
H
Kopjar
Branko
B
Fleming
Barbara
B
Jesse
Robert L
RL
Rusch
Roxane
R
Fihn
Stephan D
SD
D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary / Q000706:statistics & numerical data; D006328:Cardiac Catheterization / Q000706:statistics & numerical data; D002561:Cerebrovascular Disorders / Q000453:epidemiology; D015331:Cohort Studies; D001026:Coronary Artery Bypass / Q000706:statistics & numerical data; D003704:Dementia / Q000453:epidemiology; D003920:Diabetes Mellitus / Q000453:epidemiology; D004363:Drug Utilization / Q000706:statistics & numerical data; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006333:Heart Failure / Q000453:epidemiology; D017052:Hospital Mortality; D006760:Hospitalization; D006787:Hospitals, Veterans; D006801:Humans; D007674:Kidney Diseases / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D009369:Neoplasms / Q000453:epidemiology; D017063:Outcome Assessment, Health Care; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology
D005343:Fibrinolytic Agents