title: Mind the gap: socio-economic and gender inequalities in service delivery and mortality in patients hospitalised with Acute Coronary Syndrome
Creators: name: Zhang, Ruiqi
Publisher: name: University of Glasgow
Year: 2022

description: Coronary heart disease persists as the leading cause of death in most countries and is severely affected by health inequalities. This thesis examined socioeconomic and sex disparities in presenting characteristics, treatment and all-cause mortality in patients hospitalized with myocardial infarction (MI) or angina. It is composed of four independent but related studies. Socioeconomic status and its association with healthcare and mortality after acute coronary syndrome: a systematic review (study 1) Aims: In the first section of the thesis, a systematic review was conducted to determine the associations of SES with mortality and access to invasive cardiac procedures after ACS hospitalisation. Methods and results: Electronic databases (Ovid Medline® and Embase) were searched in December 2017. The impact of SES was analysed separately for each outcome: 1) all-cause mortality at 30 days and at 1 year; 2) use of invasive cardiac procedures during hospitalisation split by coronary angiography (CAG) and percutaneous coronary intervention (PCI). Meta-analyses were conducted using random effects models. Subgroup analysis were performed to separate any differences across different measures of SES, countries of study, final diagnosis and year of publication. Sixty studies were included. The overall results of the meta-analyses provided evidence for significantly higher risk of death among ACS patients in lower socioeconomic categories for both 30-day and 1-year mortality. Compared to ACS patients of the highest socioeconomic position, the risk of death at 30-days in the lowest group increased by 24% (RR 1.24, 95% confidence interval (CI) 1.17-1.31). The lowest socioeconomic category was also associated with increased risk of death at 1-year (RR 1.20, 95% CI 1.14-1.26). Socioeconomic disparities were also found in invasive cardiac procedure rates in patients hospitalised with ACS. Overall, groups with the poorest level of SES had reduced access to coronary angiography (RR 0.70, 95% CI 0.59-0.82) and PCI (RR 0.82, 95% CI 0.74-0.90). Results were consistent across subgroup and sensitivity analyses. Conclusion: In patients with ACS, it is well established that a person’s socioeconomic status has modest but profound effects on the utilisation of invasive cardiovascular services and mortality. These relationships have been demonstrated for different dimensions of area-level and individual level SES measures, across different countries and have not improved over time. Differences in mortality across socioeconomic strata is greatly attenuated after considering treatments and related factors, while targeting poor geographical access to healthcare facilities may be the most efficient way to decrease the inequality gap in utilisation of invasive coronary procedures. In addition, inequalities in utilisation of PCI and in receiving medical attention suggest that inequalities in access to good quality care may play a role in explaining the higher case death of ACS among people with lower SES. However, the magnitude of the contribution of differences in interventional procedures to inequalities in mortality needs to be investigated further using mediation analyses.