Adherence to statin treatment and readmission of patients after myocardial infarction: a six year follow up study

Abstract

Objective: To investigate patients' adherence to statin treatment prescribed following their first myocardial infarction (MI) and to estimate the effect of adherence to statins on recurrence of MI and all cause mortality. Design: Cohort study using a record linkage database. Setting: Tayside, Scotland, UK. Patients: Patients who experienced their first MI between January 1990 and November 1995. Main outcome measures: Percentage of statin use and adherence to statins by patients after an MI and the relative risk of hospitalisation for recurrent MI. The effect of adherence on all cause mortality was also examined. The covariates used were age, sex, socioeconomic deprivation, serum cholesterol concentration, diabetes mellitus, cardiovascular drug use, and other hospitalisations. Results: Of 5590 patients who experienced an incident MI, 717 (12.8%) experienced at least one further MI. Only 7.7% of patients used statins after an MI during the study period. Compared with those not taking statins, those who had 80% or better adherence to statin treatment had an adjusted relative risk of recurrent MI of 0.19 (95% confidence interval (CI) 0.08 to 0.47) and all cause mortality of 0.47 (95% CI 0.22 to 0.99). There was no significant reduction in either end point for those who were less than 80% adherent to statins. Conclusions: Despite the infrequent use of statin during the study period, good adherence to statin treatment was associated with lower risk of recurrent MI.

Cohort study examining tamoxifen adherence and its relationship to mortality in women with breast cancer

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Statin Treatment in Diabetes Mellitus

“…The 5% of patients who were 80% adherent with statin therapy were 81% less likely to have a recurrent MI and 53% more likely to survive the observation period. 16 Based on analyses of the third National Health and Nutrition Examination Survey (NHANES-III), which examined patients between 1988 and 1994, there are 8.2 million people in the United States with diabetes and no clinical evidence of CVD with an LDL cholesterol ≥ 100 mg/dl and only 1.6 million with an LDL < 100 mg/dl. If statin therapy were administered to lower LDL < 100 mg/dl, 71,000 major coronary events could be prevented annually including 13,000 among people with LDL levels between 100 and 129 mg/dl at an annual incremental cost per person at risk of $480-950 for those with LDL 100-129 mg/dl and $590-1,920 for those with LDL ≥ 130 mg/dl.…”

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