Management and outcomes of acute myocardial infarction in patients with Alzheimer's disease: a study of 2.7 million individuals with myocardial infarction, 2010 - 2020

Abstract Background As a consequence of population ageing, the prevalence of Alzheimer’s Disease (AD) is rising. Evidence-based clinical decision-making for those with AD that present with acute myocardial infarction (MI) is limited by difficulty in identifying which patients will benefit from guideline-directed invasive management versus a more conservative approach. Purpose This study aimed to assess the prevalence of AD in patients presenting with acute MI and characterise its association with patient factors, treatment utilisation and clinical outcomes. Methods A retrospective cohort study was conducted using the United States National Readmission Database (NRD), 2010–2020. International Classification of Disease (ICD; version 9 and 10, Clinical Modification) codes were used to identify patients with a principal diagnosis of MI, pre-existing AD and other comorbidities, in addition to invasive procedures (invasive coronary angiography ± percutaneous coronary intervention [PCI] or coronary artery bypass graft [CABG] surgery). Logistic and flexible parametric survival models (adjusted for age, sex, MI subtype, smoking status, comorbidities, and MI treatments) were used to evaluate the association between AD and in-hospital and 1-year clinical outcomes, respectively. Results Overall, 2,750,798 individuals were admitted with MI during the study period, of which 35,367 had Alzheimer’s disease; 1.3%; Figure 1). Patients with AD were older (median age 85 vs. 67), more likely to be female (57.6 vs. 37.9%), present with non-ST-elevation MI (77.7 vs. 69.5%), and had a greater burden of individual comorbidities (including chronic kidney disease and depression) and multimorbidity (≥2 long-term conditions; 77.4 vs. 71.0%). Patients with AD were less likely to undergo invasive management (coronary angiography ± PCI/CABG; 27.7 vs 77.6%; p < 0.001; adjusted odds ratio [aOR] 0.24, 95% confidence intervals [CI] 0.23–0.25). Patients with AD had greater mortality both in-hospital (11.9 vs. 5.2%; aOR 1.30 (95% CI: 1.26–1.35, p < 0.001) and 1-year (15.9 vs. 7.3%; adjusted hazard ratio [aHR] 1.21; 95% CI 1.18–1.25). AD was associated with a greater risk of major adverse cardiovascular events (MACE; myocardial infarction, stroke or all-cause mortality; 27.8 vs. 17.7%; aHR 1.10, 95% CI 1.08–1.12) at 1-year post-MI (figure 2). However, patients with AD that were selected to undergo invasive management experienced reduced MACE (aHR 0.74, 95% CI 0.70–0.77) and all-cause mortality (aHR 0.53, 95% CI 0.49–0.57) in comparison to those managed conservatively. Conclusions Patients with Alzheimer’s Disease presenting with acute MI face a poor prognosis marked by a high rate of MACE and all-cause mortality. Future research should seek to identify those who benefit most from invasive management. At present, individualised, shared and multidisciplinary decision-making is key to guide the management of patients with AD that present with acute MI.