Changes in the treatment and outcomes of acute myocardial infarction in Quebec, 1988-1995.
BACKGROUND
Few studies have reported population-based information on the treatment trends and outcomes of patients who have had an acute myocardial infarction (AMI). We therefore examined patterns of care and outcomes for AMI patients in Quebec, Canada, between 1988 and 1995.


METHODS
Longitudinal data files of hospital admissions in Quebec (Med-Echo database) and inpatient and outpatient services (Régie de l'Assurance Maladie du Québec database) were used to construct cohorts of all AMI patients in the province between 1988 and 1995. Temporal trends in the use of cardiac procedures after an AMI, discharge prescriptions and mortality rates were examined.


RESULTS
Between 1988 and 1995 the age- and sex-adjusted rates of AMI in the Quebec population declined (148 per 100,000 in 1988 to 137 per 100,000 in 1995). The use of intensive cardiac procedures increased in the same period; the 1-year cumulative incidence rate of catheterization increased from 28% in 1988 to 31% in 1994, that of angioplasty rose from 8% to 15% and that of coronary artery bypass surgery from 6% to 8%. Prescriptions for ASA, beta-blockers, lipid-lowering agents and angiotensin-converting enzyme inhibitors increased, and prescriptions for nitrates and calcium antagonists decreased. These temporal changes were paralleled by a decrease in mortality rates post-AMI. All-cause 1-year cumulative incidence mortality rates decreased from 23% in 1988 to 19% in 1994.


CONCLUSIONS
The decrease in AMI-related mortality in Quebec between 1988 and 1995 may be linked to changes in treatment strategies (i.e., increased use of cardiac surgical procedures and medications shown to increase survival).
Division of Clinical Epidemiology, Montreal General Hospital, QC. mdlp@musica.mcgill.ca
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L
Pilote
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F
Lavoie
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Ho
M J
MJ
Eisenberg
D000367:Age Factors; D000368:Aged; D000553:Ambulatory Care / Q000706:statistics & numerical data; D015906:Angioplasty, Balloon, Coronary / Q000706:statistics & numerical data; D006328:Cardiac Catheterization / Q000706:statistics & numerical data; D002317:Cardiovascular Agents / Q000627:therapeutic use; D015331:Cohort Studies; D016001:Confidence Intervals; D001026:Coronary Artery Bypass / Q000706:statistics & numerical data; D019992:Databases as Topic; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D009203:Myocardial Infarction / Q000401:mortality / Q000628:therapy*; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data*; D010343:Patient Admission / Q000706:statistics & numerical data; D010351:Patient Discharge / Q000706:statistics & numerical data; D011159:Population Surveillance; D011792:Quebec / Q000453:epidemiology; D012189:Retrospective Studies; D012737:Sex Factors; D015996:Survival Rate; D016896:Treatment Outcome
D002317:Cardiovascular Agents