Aortic stenosis (AS) is the narrowing of the aortic valve and is the most common type of valve disease requiring surgery in high-income countries. It is estimated that 5% of adults aged 65 years have AS, with this number expected to rise with the ageing population. Small studies have suggested differences in treatment and outcomes for ethnic minorities and people from low socioeconomic groups. It is unclear whether these are due to differences in disease burden, symptoms, health-seeking behaviour or rates of diagnosis and referral. Ethnic minority groups make up 15% of the population in England but are massively under-represented in research studies on valve disease. Covid-19 has highlighted and potentially widened health inequalities. The impact of these on the outcomes of patients with AS is unknown.
There are no definitive epidemiological data on AS by ethnicity or socio-demographics in the UK. The OxValve study was a large community echocardiographic screening study that identified 1.3% of individuals >65 years had undiagnosed AS. However, this cohort comprised predominantly White patients (99%) in an affluent setting, and does not represent a diverse population.
This will be the first nationwide study to estimate these differences (if any) and subsequently, differences in treatment and results. We aim to present comprehensive, good quality data that may help to determine potential health inequalities and tailor future research strategies and healthcare policies to address these.
Aortic stenosis (AS) is the commonest valve disease requiring intervention in the west. Ethnic minorities make up 15% of the population in England, but are under-represented in research, with differences in treatment and outcomes also shown for those from ethnic minorities and low socio-economic groups. The overall prevalence of AS in England is unknown. The aim of this study is to determine sociodemographic differences in the incidence, prevalence, treatment, and outcomes of patients with AS.
All adult patients with a first diagnosis of AS in Clinical Practice Research Datalink (CPRD) database from January 2000 will be included to determine socio-demographic split of diagnosis, referral to secondary care and clinical outcomes. A random sample of one million adults will also be extracted to determine the incidence and prevalence of AS, split by socio-demographic factors, within that group. The annual incidence rate will be defined as the number of new AS cases divided by the number of person-years at risk, for each calendar year. The annual prevalence will be calculated by dividing the number of people ever diagnosed with AS who remain alive on 1st July, by the total number of eligible people at the same time point. Linked Hospital Episode Statistics (HES) data will confirm ethnicity and determine clinical outcomes (referral to secondary care, aortic valve intervention, hospitalisation with heart failure, arrhythmia, or syncope). Linkage to Office of National Statistics (ONS) Mortality data will determine cardiovascular and all-cause mortality.
This study is expected to benefit public health by providing the first epidemiological estimate of the incidence and prevalence of AS across ethnic groups and sexes, that may help to identify potential health inequalities and tailor future policies/strategies to address these.
Key variables: Aortic stenosis; Ethnicity; Socio-economic status (SES); Sex
Outcomes: Referral to secondary care for AS-related reasons; Hospitalisation for heart failure, arrhythmia, or syncope; Aortic valve replacement (AVR); Transcatheter aortic valve implantation (TAVI); Cardiovascular mortality; All-cause mortality
Anvesha Singh - Chief Investigator - University of Leicester
Saadia Aslam - Corresponding Applicant - University of Leicester
Claire Lawson - Collaborator - University of Leicester
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation