Impact of restrictive prescription plans on heart failure medication use.
BACKGROUND
Prescription plans frequently use restrictive strategies to control drug expenditures. Increased restrictions may reduce access to evidence-based therapy among patients with chronic disease. We sought to evaluate the impact of increased restrictions on medication use among heart failure (HF) patients.


RESULTS
We conducted a population-based cohort study of administrative data from 3 Canadian provinces. During 1998 to 2001, Quebec (QC) had a minimally restrictive plan, whereas Ontario (ON) and British Columbia (BC) had more restrictive prescription plans. We evaluated drug use at 30 days of discharge stratified by prescription plan. Provincial rates of filled prescriptions for HF drugs in QC, ON, and BC were 62%, 58%, and 47% for angiotensin-converting enzyme inhibitors; 34%, 22%, and 16% for beta-blockers; 9%, 5%, and 3% for angiotensin receptor blockers; and 79%, 76%, and 62% for loop diuretics, respectively. In multivariate analyses, patients residing in provinces with restrictive plans were less likely to be prescribed drugs that were restricted, such as beta-blockers (odds ratio, 0.53; 95% CI, 0.46 to 0.60; 0.36, 0.29 to 0.44, for ON and BC, respectively) and angiotensin receptor blockers (0.50, 0.45 to 0.56; 0.38, 0.32 to 0.46, for ON and BC, respectively), than drugs with no restrictions, such as loop diuretics (0.81, 0.74 to 0.88; 0.40, 0.36 to 0.45, for ON and BC, respectively) and angiotensin-converting enzyme inhibitors (0.80, 0.75 to 0.86; 0.47, 0.43 to 0.52, for ON and BC, respectively).


CONCLUSIONS
Among HF patients, residing in a province with a more restrictive prescription plan may be associated with lower use of restricted HF medications over and above the expected regional differences in HF drug use across provinces.
Thanassoulis
George
G
Divisions of Clinical Epidemiology, Cardiology, and Internal Medicine, McGill University Health Center, Montreal, Quebec, Canada.
Karp
Igor
I
Humphries
Karin
K
Tu
Jack V
JV
Eisenberg
Mark J
MJ
Pilote
Louise
L
D000319:Adrenergic beta-Antagonists / Q000191:economics / Q000627:therapeutic use; D000368:Aged; D000369:Aged, 80 and over; D047228:Angiotensin II Type 1 Receptor Blockers / Q000191:economics / Q000627:therapeutic use; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000191:economics / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000191:economics / Q000627:therapeutic use; D002170:Canada / Q000453:epidemiology; D002317:Cardiovascular Agents / Q000191:economics / Q000627:therapeutic use*; D015331:Cohort Studies; D015897:Comorbidity; D004232:Diuretics / Q000191:economics / Q000627:therapeutic use; D016527:Drug Costs; D011307:Drug Prescriptions / Q000191:economics / Q000706:statistics & numerical data*; D005260:Female; D006291:Health Policy; D006333:Heart Failure / Q000188:drug therapy* / Q000191:economics / Q000453:epidemiology*; D006801:Humans; D019458:Insurance Coverage / Q000191:economics; D008297:Male; D015999:Multivariate Analysis; D016903:Drug Monitoring
D000319:Adrenergic beta-Antagonists; D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D002317:Cardiovascular Agents; D004232:Diuretics