title: Magnitude and nature of noncompliance with treatment using isosorbide dinitrate in patients with ischemic heart disease.
abstract: Isosorbide dinitrate is one of the most commonly prescribed medications for the treatment of ischemic heart disease. It has been demonstrated to be ineffective relative to placebo when taken inappropriately. This study objectively documents the magnitude and nature of compliance in 68 ambulatory patients who were prescribed isosorbide dinitrate three times a day. Each patient received a 9-week supply of medication in a vial equipped with a computerized monitor (MEMS-4 cap; APREX Corporation, Fremont, CA) and were informed as to the purpose of the study. Of the patients, 74% were classified into the low and 16% into the high compliance category, defined as compliant < 70% and > or = 85% of study days, respectively. The mean (+/- SD) percent days in which isosorbide dinitrate was taken three times was 66% (+/- 29), and the mean number of days in which it was taken three times with a 10-hour "nitrate free period" was 53% (+/- 31). It is concluded that the magnitude of noncompliance in patients prescribed isosorbide dinitrate three times daily is substantial (74%). The nature of this noncompliance is often due to failure to observe a 10- to 12-hour nitrate free period. Given the need to take isosorbide dinitrate appropriately and given the demonstrated magnitude of noncompliance, physicians should take these factors into consideration when selecting this agent for the management of coronary artery disease relative to other pharmacologic options.
authors.affiliation: Department of Pharmacy Practice, University of Minnesota College of Pharmacy, Minneapolis 55455, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Straka
authors.forename: J T
authors.initials: JT
authors.lastname: Fish
authors.forename: S R
authors.initials: SR
authors.lastname: Benson
authors.forename: J T
authors.initials: JT
authors.lastname: Suh
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D004361:Drug Tolerance; D005260:Female; D006801:Humans; D007548:Isosorbide Dinitrate / Q000008:administration & dosage* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000188:drug therapy*; D011795:Surveys and Questionnaires; D016312:Treatment Refusal; D014665:Vasodilator Agents / Q000008:administration & dosage* / Q000627:therapeutic use
chemical_list: D014665:Vasodilator Agents; D007548:Isosorbide Dinitrate