Disparities in the management of non-ST-segment elevation myocardial infarction in the United States

Highlights

• NSTEMI patients ≥80 years get PCI-DES one artery at <50% of the rate in <80 years.

• Intervention is equally beneficial in both patients <80 and ≥ 80 years.

• Women are 21.5% less likely to get intervention for NSTEMI compared to men.

• Non-white race has a 16.8% less likelihood of intervention.

• Non-Medicare/Medicaid: 40% lower mortality in age < 80; 16% higher intervention.

Abstract

Guidelines recommend managing patients aged ≥75 with non-ST-segment elevation myocardial infarction (NSTEMI) similar to younger patients. We analyze disparities in NSTEMI management and compare those ≥80 years to those <80 years. This is a matched case-control study using the 2016 National Inpatient Sample data of adults with NSTEMI receiving percutaneous coronary intervention with drug-eluting stent (PCI-DES) - one artery or no intervention. We included the statistically significant variables in univariate analysis in exploratory multivariate logistic regression models. Total sample included 156,328 patients, out of which 43,265 were ≥ 80 years, and 113,048 were < 80 years.

Patients ≥80 years were more likely to not have an intervention (73.3%) when compared to those <80 (44.1%), P < 0.0005. Regardless of age, PCI-DES-one artery improved survival compared to no intervention (Age < 80: OR 0.230, 95% CI 0.189–0.279, and ≥ 80: OR 0.265, 95% CI 0.195–0.361, P < 0.0005). Women (OR 0.785, 95% CI 0.766–0.804, P < 0.0005) and non-white race (OR 0.832, 95% CI 0.809–0.855, P < 0.0005) were less likely to receive an intervention. Non-Medicare/Medicaid insurance was associated with 40% lower likelihood of dying in <80 age group (OR 0.596, 95% CI 0.491–0.724, P < 0.0005), and 16% higher chance of intervention overall (OR 1.160, 95% CI 1.125–1.197, P < 0.0005). Patients aged ≥80 with NSTEMI were 29% less likely to receive an intervention compared to patients aged <80, even though patients >80 derived similar mortality benefits from the intervention. There were gender, payor, and race-based disparities in NSTEMI management in 2016.

Introduction

Disparities in the care of myocardial infarction due to age, race, gender, socioeconomic factors, and geographic location have been reported [1]. More specifically, disparities in percutaneous invasive strategies for non-ST-segment elevation acute coronary syndrome (NSTEMI) continue to exist for octogenarians, women and marginalized communities. Most patients hospitalized for non-ST-segment elevation acute coronary syndrome (NSTEMI) are >65 years old [2]. Analysis of the Global Registry of Acute Coronary Events (GRACE) revealed a low rate of coronary angiography in the elderly, even though invasive strategy had significant mortality benefit [3]. Percutaneous coronary intervention (PCI) has been found to be safe in octogenarians, and complete revascularization and stenting were independent predictors of 2-year event-free survival [4]. A meta-analysis of pooled patient data from three large trials showed that an early invasive strategy was associated with a significant decrease in a 5-year composite of death and myocardial infarction in patients ≥75 years [5]. The American College of Cardiology/American Heart Association 2014 guidelines (Class I Recommendations, Level of evidence: A) recommend managing patients aged ≥75 years with NSTEMI using the same guideline-directed medical therapy and early invasive strategy and revascularization as appropriate, since early invasive strategy benefits older patients the same or better than younger patients [6].

Even though evidence strongly favors early invasive strategy in older adults, age ≥ 75 years was found to be the most influential factor for the avoidance of cardiac catheterization in patients with NSTEMI [7]. In another study, for patients between 65 and 75, the early invasive strategy showed a 39% reduction in death or myocardial infarction at 6 months compared with conservative strategy; however, a similar study conferred a 56% relative reduction for patients above the age of 75% [8]. Data from GRACE also showed similar results with a reduction in the 6-month mortality particularly significant in very elderly (odds ratio (OR) 0.68; confidence interval (CI) 0.49–0.95) [3]. In a meta-analysis of all the studies from 1990 to 2016, thirteen studies that included four randomized controlled trials and nine observational studies with a total population of 832,007 elderly patients presenting with non-ST-segment elevation acute coronary syndrome (NSTE-ACS), the early invasive approach significantly reduced the risk of death at follow-up from 6 months to 5 years (relative risk (RR) 0.65; CI 0.59–0.73; P < 0.001) [9]. This benefit was observed mainly in the observational studies. It should also be noted that the risk of any bleeding occurring in hospital was higher with the invasive strategy (RR 2.51; CI 1.53–4.11; P < 0.001) however, no difference in the in-hospital major bleeding was observed (RR 1.78; CI 0.31–10.13; P = 0.514).

Such disparities were also observed between men and women. Based on the National (Nationwide) Inpatient Sample (NIS) data between 2010 and 2014, women with NSTE-ACS were less likely to receive revascularization with PCI compared with men (51.1% vs. 58.2%; OR 0.86; CI 0.78–0.94] or coronary artery bypass grafting (CABG) [7.9% vs. 10.1%; OR 0.64;CI 0.54–0.75) [10]. It seems that data continues to remain significant even in 2016 despite changes in contemporary practice. Although studies and guidelines look mostly at adults older ≥75 years, this study aims to build on the limited evidence-based literature concentrating on very elderly patients (older than 80 years) [3,4].