Drug prescriptions after acute myocardial infarction: dosage, compliance, and persistence.
BACKGROUND
Although it has been well documented that aspirin, beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, and lipid-lowering drugs are under-prescribed for patients with acute myocardial infarction (Am Heart J 2003;145:438-44.), few studies have examined dosage and long-term compliance and persistence patterns for the use of these drugs after AMI.


METHODS
Using Quebec administrative data on all elderly (aged > or =65 years) survivors of hospital admissions for AMI between 1996 and 1998 (n = 14,057), we studied the discharge prescriptions, dosages, patient compliance, and persistence during this period for aspirin, beta-blockers, ACE inhibitors, and lipid-lowering drugs.


RESULTS
Rates of discharge medications were suboptimal (aspirin 65%, beta-blockers 54%, ACE inhibitors 45%, lipid-lowering drugs 21%). Most patients with prescriptions for aspirin and ACE inhibitors were prescribed dosages equivalent to those administered in clinical trials (99% and 88%, respectively). In contrast, only 20% of patients with beta-blocker prescriptions and 48% of patients with lipid-lowering drug prescriptions were prescribed clinical trial doses. For patients with discharge prescriptions, 1-year compliance rates were high (aspirin 74%, beta-blockers 74%, ACE inhibitors 70%, lipid-lowering drugs 84%), as were the 1-year persistence rates (aspirin 71%, beta-blockers 72%, ACE inhibitors 69%, lipid-lowering drugs 80%).


CONCLUSIONS
Although cardiac drugs are under-prescribed to patients with AMI, once prescribed, patients are likely to adhere to these prescriptions, with high rates of compliance and persistence.
Simpson
Ewurabena
E
Division of Clinical Epidemiology, Montreal General Hospital, Montreal, Quebec, Canada.
Beck
Christine
C
Richard
Hugues
H
Eisenberg
Mark J
MJ
Pilote
Louise
L
D000208:Acute Disease; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D001241:Aspirin / Q000008:administration & dosage / Q000627:therapeutic use*; D002986:Clinical Trials as Topic / Q000706:statistics & numerical data; D019992:Databases as Topic; D004334:Drug Administration Schedule; D005260:Female; D019983:Guideline Adherence; D006753:Hospital Records; D006801:Humans; D000960:Hypolipidemic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D009203:Myocardial Infarction / Q000188:drug therapy*; D010349:Patient Compliance; D010351:Patient Discharge; D010818:Practice Patterns, Physicians'; D011792:Quebec
D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D000960:Hypolipidemic Agents; D001241:Aspirin