After being hospitalized for a myocardial infarction (MI), patients with dual Medicare-Medicaid eligibility fared worse than their Medicare-only peers following discharge, investigators found. Adherence to medication after MI was low in both groups, though patients eligible for Medicare and Medicaid — and therefore of lower socioeconomic class by definition — had better adherence to their medications at 1 year (36.4% versus 30.0% for patients only on Medicare, HR 1.55, 95% CI 1.39-1.74), according to Jacob A. Doll, MD, of Duke University School of Medicine in Durham, N.C., and colleagues in their analysis of Medicare data published online in JAMA Cardiology. Their dual eligibility, however, was also linked to greater risks: Readmission at 30 days (HR 1.16, 95% CI 1.06-1.26) Death at 1 year (HR 1.24, 95% CI 1.14-1.36), and Major adverse cardiac events at 1 year (HR 1.21, 95% CI 1.12-1.31) These patients “had worse short- and long-term outcomes after MI despite the additional financial support provided by Medicaid,” the investigators wrote. “While prior studies have shown a similar association between low socioeconomic status and worse outcomes, the present study is novel in demonstrating higher rates of postdischarge medication adherence among patients with dual eligibility, presumably owing to the lower copayment burden in this population.” What’s more, according to the authors, treatment of the dual-eligibles appeared to be of poorer quality, at least according to objective metrics. Examples include “lower rates of reperfusion for ST-segment elevation myocardial infarction, revascularization for non-ST-segment elevation myocardial infarction, drug-eluting stent (DES) use, and prescription of evidence-based medications at discharge,” they wrote. “[T]here may be a perception among clinicians that dual-eligible patients are less likely to adhere to medications owing to cost. This may contribute to lower usage rates of revascularization and DES, owing to concerns about discontinuation of dual-antiplatelet therapy,” Doll and colleagues wrote. “Our analysis indicates that these concerns should not be limited to the dual-eligible population. Nonadherence is common for all patients, and interventions to improve adherence should be applied uniformly.” “Most notably, the findings counter the stereotype that patients of lower financial means are less adherent to their medications,” according to Ian M. Kronish, MD, MPH, of Columbia University Medical Center/New York-Presbyterian Hospital, who was not involved in Doll’s study. “So long as generous prescription cost subsidies are in place, low income status was not a risk factor for nonadherence. That said, medication nonadherence was common across all income levels, and remains an important target for post-MI quality improvement efforts,” Kronish told MedPage Today. Doll and colleagues’ retrospective analysis included 17,419 Medicare patients, 27% of whom were dual eligible. This subgroup was more likely to be female, nonwhite, and have a higher prevalence of comorbidities. Patients in this cohort were also more likely to present with non-ST-segment elevation myocardial infarction. The hazard ratios reported in the study reflected adjustments for these factors and for in-hospital treatment differences. Doll’s group acknowledged that the investigation was hindered by its retrospective nature and its inherent caveats, among them unmeasured confounders and missing key information — such as pill counts and specific level of financial assistance given to each patient — that would have provided more precise data on medication adherence and socioeconomic status. Even so, their study “highlights the fact that failure to prescribe optimal medical therapy for dual eligible patients may partially underlie disparities in post-MI outcomes, and that interventions to reduce disparities in post-MI treatment are in order for dual-eligible patients,” Kronish said. “Prior studies have clearly shown that physicians are terrible at guessing which of their patients is nonadherent to treatment.” “Future studies should assess the extent to which conscious and unconscious biases based on income status influence physician estimations of their patients’ adherence status, and whether these biases, in turn, adversely influence physician management of post-MI patients,” he suggested. Disclosures The study was supported by the Agency for Healthcare Research and Quality. Doll and Kronish disclosed no relevant conflicts of interest. Study co-authors reported relationships with Janssen, Boehringer Ingelheim, Merck, Sanofi, Bayer, AstraZeneca, Eli Lilly, Daiichi Sankyo, Bristol Myers Squibb, Boston Scientific, Gilead, GlaxoSmithKline, Regeneron, and Premier.