Director of Public Health Annual Report 2022: Preventing heart disease and stroke in Buckinghamshire
3.2 Differences between ethnic groups
A note on terminology: This section summarises what the evidence tells us about cardiovascular disease and ethnicity.
This report has used the UK Government guide to writing about ethnicity. However, the ways that ethnicity has been defined and analysed by researchers varies for some studies. Where this is the case, we have used the same language, so that we are accurate in our description of the evidence but have noted the variation with a *.
Many studies use aggregated ethnic groups - in particular South Asian and black groups, for whom the risks are higher - as a whole. Recognising that these South Asian and black ethnic categories include diverse groups of people, where studies have analysed ethnic groups that refer to nationalities, they are provided below.
Different ethnic groups have different risks of cardiovascular disease. Asian and black groups in the UK have a higher risk of cardiovascular disease but the type of cardiovascular disease underlying this risk differs between different ethnic groups. There is less evidence available for European groups living in the UK, although Central and Eastern European countries have the highest death rates from cardiovascular disease in Europe (defined as WHO’s European Region) once the age of the population has been considered (for this reason, much research uses ‘white British’ people as a comparator group). Gypsy, Romany and Traveller groups are known to have worse health outcomes compared to other ethnic minorities,86 but there is little specific evidence available to understand the contribution that cardiovascular disease plays. The reason for these differences is complex and not always well understood, however, by working with people from ethnic minority backgrounds to identify and address known risk factors, we can reduce their risk of cardiovascular disease.
3.2.1 South Asian ethnic groups
People from South Asian groups are more likely to develop cardiovascular disease and are more likely to die from cardiovascular disease compared to white groups. *South Asian ethnicity applies to people whose ethnic roots originate from India, Pakistan, Bangladesh, Sri Lanka, Nepal and Bhutan.
South Asian people have the highest risk of death from heart disease of any ethnic group, a 50% higher risk than the population of England and Wales.
South Asian people also tend to develop heart disease at a younger age. South Asian groups are also more likely to have a stroke and to die from stroke, compared to white British groups.
South Asian men develop cardiovascular disease, on average around eight years younger than white men (60.4 years vs. 68.2) and South Asian women develop cardiovascular disease an average of around 11 years earlier than white women (62.9 vs. 74.2).
Death from ischaemic heart disease was highest for men and women in the Bangladeshi, Pakistani and Indian ethnic groups, compared to other ethnic groups.
Inequalities in clinical/biological risk factors
The primary clinical conditions that drive the difference in risk of death from cardiovascular disease for immigrant South Asian groups are ischaemic heart disease and type 2 diabetes.
People from South Asian groups are up to six times more likely to develop diabetes than people in white groups.
British South Asian (this paper uses the term ‘Indian Asian’, defined as from the Indian subcontinent) groups are more likely to develop diabetes at a younger age than European* groups (age 62 years vs 67). By the age of 80, close to half (40-50%) of South Asian people will have diabetes – this is twice the prevalence in Europeans*.
Obesity (defined as a BMI of 30.0kg/m2 or above) is associated with an increased risk of developing diabetes. For South Asian ethnic groups, the risk of diabetes increases at a lower BMI. The same risk of developing type 2 diabetes as is found in white populations at a BMI of 30kg/m2 or over is found at a much lower BMI of 23.9 kg/m2 for South Asian populations.
Ethnic differences in cardiovascular disease risk persist and are more pronounced in people with diabetes. Death from heart disease in people from South Asian groups with diabetes is around three times higher compared to people from white groups with diabetes.
South Asian adults do not have higher total cholesterol overall compared to white people, but they have lower levels of HDL (‘good’) cholesterol and higher levels of triglycerides (associated with poorer heart health).
The prevalence of high blood pressure varies between South Asian ethnic groups. There is evidence that for some South Asian ethnic groups (in particular, Indian ethnic groups), levels of high blood pressure are slightly higher than is seen in the white population. In other South Asian groups, levels of high blood pressure are moderately lower for Pakistani people and markedly lower for people from Bangladeshi ethnic groups. However, this pattern is not found in children - South Asian children have been found to have higher blood pressure compared to white children. The proportion of people from Asian groups with controlled blood pressure (defined as mean systolic BP <140 mm Hg and diastolic BP <90 mm Hg, among people who reported previously being informed of a hypertension diagnosis by a health professional as well as use of antihypertensive medication) is higher (44.4%) than for white groups (38.0%) in the UK, although this is not statistically different when adjusted for factors such as age and sex.
National data show that adults in Asian (8.3%) ethnic groups are less likely to smoke when compared with people of white ethnic groups (14.4%). Asian men (13.9%) are more likely to smoke compared with Asian women (2.9%) but less likely to smoke than white men (15.8%).
National survey data show that fewer Asian people (*in this research, the formal ethnic category used is ‘Asian, excluding Chinese’) have a ‘physically active’ lifestyle (defined as 150 minutes or more of activity per week) than any other ethnic group. The COVID-19 pandemic has had a negative impact on activity levels across all ethnic groups but has disproportionately affected Asian adults.
Asian women are less active (46%) than Asian men (50%) and have the lowest level of activity of all gender and ethnicity categories.
There is some evidence that physical activity levels may have increased from first to second generation South Asian people living in the UK. Research suggests that there is variation in participation in vigorous physical activity for children from certain ethnic minority groups – children from mixed ethnicity groups spent more time doing vigorous exercise compared to white children, whilst Pakistani and Bangladeshi children on average performed less.
Adults from South Asian ethnicities tend to have lower weight compared with white groups, but their risk from cardiovascular disease and diabetes increases at a lower body mass index. Weight distribution is also associated with cardiovascular disease risk and particularly fat around the waist increases the risk of cardiovascular disease and this weight distribution is known to be higher in South Asian people.
Data from the National Child Measurement Programme indicate that in 2020/21, the proportion of children in Reception year and Year 6 at school that were obese was higher than average for children from Asian groups.
People from Asian groups are less likely to consume alcohol to a hazardous, harmful or dependent level and South Asian people are more likely to abstain from drinking alcohol.
Access to treatment
There is evidence that although incidence, morbidity and mortality rates from cardiovascular disease are higher for people of South Asian ethnicity, once people from South Asian ethnic groups have a diagnosis of coronary disease, they have better outcomes compared to white people. Therefore, it has been suggested that to address inequalities for South Asian groups, efforts should focus on stopping cardiovascular disease developing in the first place, i.e., primary prevention. However, people from Pakistani, Indian, and Bangladeshi groups also report a poorer experience of using health care services. There is some evidence of variation in the management of cardiovascular disease risk specifically for people from ethnic minorities with diabetes - analysis of GP records from selected practices in UK suggested that people of South Asian ethnicity with type 2 diabetes were 9% less likely to receive a statin compared with European* people, where guidelines indicated they should be prescribed.
3.2.2 Black ethnic groups
People from black ethnic groups tend to have a lower risk of heart disease but are more likely to have, and die from, high blood pressure and stroke than other ethnic groups.
They are also more likely to have a stroke at a younger age than white groups. Black men develop cardiovascular disease, on average, five years earlier than white men (62.8 years vs. 68.2) and black women develop cardiovascular disease an average of around 13 years earlier (61.4 years vs. 74.2).
Inequalities in clinical/biological risk factors (black ethnic groups)
High BP (blood pressure) (black ethnic groups)
Prevalence of high blood pressure in black people in the UK may be up to three or four times higher than in white people.
There is evidence that blood pressure is less likely to be controlled4 in black groups compared to all other ethnic minorities (e.g., 35.7% of all hypertensive patients controlled to target vs. 38.0% white groups) and this difference was statistically significant after adjustment for age, sex, and other factors.
Diabetes (black ethnic groups)
People from black ethnic groups are up to three times more likely to develop diabetes and have a higher risk of dying from diabetes compared with the white population.
Obesity levels are higher in black groups and the risk of diabetes increases at a lower body mass index. Obesity (defined as a BMI of 30.0 kg/m2 or above) is associated with an increased risk of developing diabetes. For black ethnic groups the risk of diabetes increases at a lower BMI. The same risk of developing type 2 diabetes as is found in white populations at a BMI of 30kg/m2 or over is found at the lower BMI of 28.1kg/m2 for black populations.
People of African Caribbean heritage have lower cholesterol levels than Europeans*, higher levels of HDL (‘good’) cholesterol and lower levels of triglycerides than white people.
Health behaviours (black ethnic groups)
National data show that adults in black (9.6%) ethnic groups are less likely to smoke when compared with people of white ethnic groups (14.4%). Black men (13.0%) are more likely to smoke than black women (7.0%) but less likely to smoke than white men (15.8%).
Data from the National Child Measurement Programme indicate that in 2020/21, the proportion of children in Reception year and Year 6 at school that were obese was higher than average for children from black ethnic groups.
People from black ethnic groups are less likely to consume alcohol to a hazardous, harmful or dependent level.
Access to treatment (black ethnic groups)
Black populations tend to have lower than expected rates of healthcare use.
Analysis of GP records from selected practices in UK suggested that people of African/African Caribbean ethnicity with type 2 diabetes were 24% less likely to receive a statin compared with European people where guidelines indicated they should be prescribed.
3.2.3 Social and economic factors
Some ethnic groups are more likely to live in more deprived areas and it is likely that this is an important part of a complex relationship between biological, environmental and behavioural factors driving the increased risk of cardiovascular disease in some groups. For example, more ethnically diverse areas are more likely to have higher levels of air pollution.
In addition, experiences of structural racism are known to affect health and may play a role through other mechanisms, for example racial discrimination has been associated with increased stress at work and stress at work has been associated with an increased risk of cardiovascular disease.