Older dual-eligibles who presented to the hospital with myocardial infarction had better rates of medication adherence compared with those who were eligible only for Medicare, according to a study. However, the dual-eligibles had higher rates of 30-day readmissions, death at one year and major adverse cardiovascular outcomes at one year. Dual eligibility status was associated with a 16% higher risk of readmission at 30 days, a 24% higher risk of death at one year and a 21% higher risk of major adverse cardiac events at one year. Of the patients who survived for a year after discharge and enrolled in Medicare Part D coverage for the full year, only 50% to 60% were adherent to each of the four classes of medications prescribed at discharge. However, dual-eligible patients were more likely to adhere to each medication. The researchers could not determine if dual eligibility, low socioeconomic status or the low income subsidy were causally related to the outcomes. They also could not rule out unmeasured confounders.