Increased morbidity, mortality and length of in-hospital stay for patients with acute coronary syndrome with pre-morbid psychiatric diagnoses

BACKGROUND: Psychiatric and cardiac comorbidities form the top two budget categories for health systems in high-income countries with evidence that psychiatric pre-morbidities lead to worse outcomes in patients with acute coronary syndrome (ACS). There are no studies examining this relationship in a national multicentre population level study in the UK, and no studies examining their impact on length of in-hospital stay (LoS) in ACS. Recognizing at-risk populations and reducing LoS in ACS is an essential part of improving patient care and cost-effectiveness.

METHODS: We investigated the impact of psychiatric diagnoses on morbidity, all-cause mortality and LoS amongst 57,668 ACS patients between Jan-2004 and Dec-2014 using the Secure-Anonymized-Information-Linkage (SAIL) databank. Demographics, admissions, cardiac and psychiatric comorbidities were identified using coded data.

RESULTS: There were a total of 3857 out of 57,668 patients who had a pre-morbid psychiatric diagnosis. The mean LoS in patients without psychiatric comorbidities was 9.78days (95% CI: 9.66-9.91). This was higher (p<0.01) in the presence of any psychiatric diagnosis (14.72), dementia (20.87), schizophrenia (15.67), and mood disorders (13.41). Patients with psychiatric comorbidities had worse net adverse cardiac events (HR 1.18, 95% CI: 1.16-1.21) and mortality rates (HR 1.26, 95% CI: 1.23-1.30).

CONCLUSIONS: Our results demonstrate that psychiatric comorbidities have a significant and clinically important impact on morbidity, mortality and LoS in ACS patients in Wales, UK. Clinicians' awareness and active management of psychiatric conditions amongst ACS patients is needed to reduce poor outcomes and LoS and ultimately the risk for patients and financial burden for the health-service.