Morphine and Cardiovascular Outcomes Among Patients With Non-ST-Segment Elevation Acute Coronary Syndromes Undergoing Coronary Angiography.

BACKGROUND: Mechanistic studies have shown that morphine blunts the antiplatelet effects of oral adenosine diphosphate receptor blockers. However, the clinical relevance of this interaction is controversial. OBJECTIVES: This study sought to explore the association between morphine and ischemic events in 5,438 patients treated with concomitant clopidogrel presenting with non-ST-segment elevation acute coronary syndromes (NSTEACS) in the EARLY ACS (Early Glycoprotein IIb/IIIa Inhibition in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome) trial. Patients not treated with clopidogrel (n = 3,462) were used as negative controls. METHODS: Endpoints were the composite of death, myocardial infarction (MI), recurrent ischemia, or thrombotic bailout at 96 h (4-way endpoint) and the composite of death or MI at 30 days. RESULTS: In patients treated with clopidogrel, morphine use was associated with higher rates of the 4-way endpoint at 96 h (adjusted odds ratio [OR]: 1.40; 95% confidence interval [CI]: 1.04 to 1.87; p = 0.026). There was a trend for higher rates of death or MI at 30 days (adjusted OR: 1.29; 95% CI: 0.98 to 1.70; p = 0.072), driven by events in the first 48 h (adjusted hazard ratio: 1.54; 95% CI: 1.07 to 2.23; p = 0.021). In patients not treated with clopidogrel, morphine was not associated with either the 4-way endpoint at 96 h (adjusted OR: 1.05; 95% CI: 0.74 to 1.49; p = 0.79; pinteraction = 0.36 ) or death or MI at 30 days (adjusted OR: 1.07; 95% CI: 0.77 to 1.48; p = 0.70; pinteraction = 0.46). CONCLUSIONS: When used concomitantly with clopidogrel pre-treatment, morphine was associated with higher rates of ischemic events in patients with NSTEACS. (EARLY ACS: Early Glycoprotein IIb/IIIa Inhibition in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome; NCT00089895).

Medication Discontinuation in the IMPROVE-IT Trial.

BACKGROUND: Although cholesterol-lowering medications can reduce the risk of recurrent cardiovascular events, premature discontinuation limits effectiveness. Discontinuation rates have not been systematically reported for lipid-lowering trials. METHODS AND RESULTS: We evaluated medication discontinuation in IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial), which evaluated placebo+simvastatin versus ezetimibe+simvastatin in patients hospitalized with the acute coronary syndrome and followed longitudinally postdischarge. Reasons for discontinuation were evaluated from randomization through study end (median 71.9 [interquartile range 51.8-85.8] months). Kaplan-Meier (KM) discontinuation rates were evaluated at 30 days, 1 year, and through year 7, and compared by treatment arm and region, with Cox proportional hazards modeling used to evaluate predictors of discontinuation. Overall, 46.7% of subjects discontinued study medication (KM rate by study end 50.9% [95% CI, 50.1%-51.7%]). The risk of discontinuation was highest early in the trial but decreased with increasing time, with a terminal KM rate per 100 person-years of 8.4 (8.2-8.6) from years 1 to 7. Discontinuation was higher in the placebo+simvastatin versus ezetimibe+simvastatin arm (KM rate 52.0% versus 49.8%, P=0.049) and was highest in the United States (7-year KM rate 57.4%). In multivariable modeling, smoking, prior revascularization, hypertension, unstable angina, female sex, nonwhite race, and US location were associated with higher discontinuation rates. CONCLUSIONS: Although discontinuation was highest early and stabilized to 8% per year, because of prolonged follow-up, most discontinuation occurred after year 1. Adding ezetimibe to statin therapy did not increase discontinuation risk. Geographic differences and patient-level factors should be considered in trial design and analysis. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00202878.