Background Following a myocardial infarction (MI), people with severe mental illness (SMI) have poorer outcomes than people without SMI. Differences in receipt of acute cardiac care between people with and without SMI may contribute to these disparities. The aim of this study was to compare receipt of acute cardiac care in people with versus without SMI and investigate the impact of the COVID-19 pandemic on any differences in care.

Methods We conducted a cohort study using data from the CVD-COVID-UK resource, which links electronic health data from multiple sources. Our cohort included adults with a non-ST-elevation MI (NSTEMI) recorded in the Myocardial Infarction National Audit Programme dataset between 1st November 2019 and 31st March 2022. We defined SMI as schizophrenia or bipolar disorder, ascertained through recorded diagnosis in primary care or hospital admission records. We examined receipt of cardiac care standards for NSTEMI, including: admission to cardiac ward; angiogram eligibility; receipt of angiogram (in those eligible); angiogram within 72 hours; secondary prevention medication prescribing at discharge, and arrangement of post-discharge cardiac rehabilitation. We used logistic regression to obtain odds ratios (ORs) for the association between SMI and receipt of each care standard, adjusting for age, sex and time period. We tested for an interaction between SMI and time period to determine if any disparities had changed since the start of the COVID-19 pandemic.

Results Among 95,125 adults with NSTEMI, 620 (0.6%) had schizophrenia and 575 (0.6%) had bipolar disorder. Compared to people without SMI and after adjusting for age, sex and period, patients with SMI were less likely to receive each care standard. For example, compared to those without SMI, those with SMI were less likely to: be admitted to a cardiac ward (schizophrenia: OR 0.72, 95% CI 0.61, 0.85; bipolar disorder: 0.74, 95%CI 0.63, 0.88); be eligible for an angiogram (schizophrenia: 0.37, 95% CI 0.29, 0.47; bipolar disorder: 0.52, 95% CI 0.40, 0.68); receive an angiogram (schizophrenia: 0.22, 95% CI 0.18, 0.28; bipolar disorder: 0.51, 95% CI 0.39, 0.66); and receive an angiogram within 72 hours (schizophrenia: 0.71, 95% CI 0.56, 0.90; bipolar disorder: 0.80, 95% CI 0.64, 1.00). We generally found no evidence that disparities had changed since the start of the COVID-19 pandemic.

Conclusion We identified marked SMI disparities in receipt of acute cardiac care among people treated in hospital for NSTEMI. Further research should seek to identify reasons for, and inform interventions to, address these disparities.