title: Effect of drug combinations on admission for recurrent myocardial infarction.
abstract: OBJECTIVE
  To determine the effect of the number of different drugs with adherence to medication of at least 70% on recurrent admission for myocardial infarction (MI) in patients with a history of MI.
  
  
  METHODS
  Nested case-control study in a dynamic cohort.
  
  
  METHODS
  PHARMO database that contains pharmacy dispensing records and hospital discharge records of 350,000 Dutch citizens.
  
  
  METHODS
  All patients admitted to hospital for first MI (ICD-9 410) from 1991 to 2000 with at least a 30-day survival after admission. Cases were admitted for recurrent MI and were matched for age, sex, and year of admission with controls who did not have a recurrent MI.
  
  
  METHODS
  Odds ratio with 95% CI for admission for recurrent MI. Exposure was the number of preventive drugs (antiplatelet agents, statins and beta blockers or ACE inhibitors) used for at least 70% of the time.
  
  
  RESULTS
  389 cases were matched with 2344 controls. The use of one drug was associated with a 6% odds reduction (95% CI 30% reduction to 28% increase) for admission for recurrent MI. The use of two or three drugs was associated with reductions of 26% and 41% (47% reduction to 3% increase and 6% to 63% reduction, respectively). Addition of one drug caused a 16% reduction (4% to 26%).
  
  
  CONCLUSIONS
  Multiple drug treatment decreases admissions for recurrent MI in patients with a history of MI. Every addition of a drug, regardless of drug class, reduces the risk even further. These results support the treatment strategies as applied in daily practice.
authors.affiliation: Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands.
authors.forename: Menno E
authors.initials: ME
authors.lastname: van der Elst
authors.forename: Marcel L
authors.initials: ML
authors.lastname: Bouvy
authors.forename: Cornelis J
authors.initials: CJ
authors.lastname: de Blaey
authors.forename: Anthonius
authors.initials: A
authors.lastname: de Boer
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D016022:Case-Control Studies; D004338:Drug Combinations; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D008297:Male; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000453:epidemiology; D009426:Netherlands / Q000453:epidemiology; D016017:Odds Ratio; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D012008:Recurrence; D012044:Regression Analysis
chemical_list: D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D004338:Drug Combinations; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D010975:Platelet Aggregation Inhibitors