The effect of schizophrenia on major adverse cardiac events, length of hospital stay, and prevalence of somatic comorbidities following acute coronary syndrome

Abstract

Aims: We aimed to investigate major adverse cardiac events (MACE: defined as all-cause mortality, re-infarction, and stroke), length of hospital stays (LOS), and comorbidities following acute coronary syndrome (ACS) in a population with schizophrenia.

Methods and results: This Danish register study included patients diagnosed with ACS in the period between 1995 and 2013 with a preceding diagnosis of schizophrenia (n = 726). Each patient was matched to a psychiatric healthy control 1:2 on sex, age, year of ACS diagnosis, and number of comorbidities (total n = 2178). After performing Cox regression and Kaplan-Meier analyses, we found that patients with schizophrenia had an increased risk of MACE [hazard ratio (HR) 1.62, 95% confidence interval (CI) 1.45-1.81], all-cause mortality (HR 2.54, 95% CI 2.22-2.90), and stroke (HR 1.51, 95% CI 1.15-1.99). No differences were found in the re-infarction rates and LOS between the populations. Patients with schizophrenia had higher prevalence's diabetes, anaemia, heart failure, cardiomyopathy, chronic obstructive lung disease, and stroke. Nonetheless, we found lower prevalence's of hypertension and hyperlipidaemia.

Conclusion: Schizophrenia is associated with an increased risk of MACE despite a lower prevalence of some diagnosed traditional cardiac risk factors which may indicate underdiagnosing of these. Awareness of treatment bias may improve this increased risk.

Keywords: Acute coronary syndrome; Myocardial infarction; Psychiatry; Quality of care; Schizophrenia.