Nationwide trends in major cardiovascular risk factors in England in the last 2 decades: Health Survey of England 2003-2019

Abstract Cardiovascular disease (CVD) accounts for a quarter of deaths annually in the UK, with more than 7.6 million people living with the disease. Hypertension, diabetes, and obesity are among the most prevalent modifiable risk factors for CVD, and the strategies to reduce the incidence and prevalence of these CV risk factors are deemed the most effective to reduce this immense toll. In the UK, over the last few decades, several health policy decisions and pathways have been developed to reduce this toll. We used data from 11 nationally representative, cross-sectional surveys from the Health Survey of England between 2003 and 2019 to evaluate trends in the prevalence of these CV risk factors and whether there has been any population-wide improvement in them. These surveys have cumulative information on 94,100 adults, and we applied sample weights, accounting for oversampling and nonresponse. We used "period definitions and cut-offs" to define those with diabetes. For example, for undiagnosed diabetes, we used glycated haemoglobin cut-off equivalent of 7% or more for years before 2011 and the current diagnostic threshold of > 6.5% thereafter. This was done to facilitate and compare the trends after accounting for changes in medical practice and understanding across this period. Similarly, hypertension was defined as doctor-diagnosed hypertension or in its absence regular use of antihypertensive medications or blood pressure ≥ 140/90mmHg (period diagnostic threshold remains unchanged during). Python and STATA were used to conduct analyses, and Join Point regression software was used to develop and compare trends. In England, from 2003-2019, mean population BMI consistently increased over this period, rising by 0.8kg/m2 from 27.6 to 28.8 kg/m2. Obesity prevalence (BMI ≥30kg/m2) increased by 5.4% from 22.6% to 28.0%. Concurrently, mean glycated haemoglobin increased by 0.36% from 6.18% to 6.54%, surpassing the current diabetes diagnostic threshold. Diabetes period prevalence surged from 4.2% to 11.6%, a trend consistent when the current diagnostic threshold was alternatively applied across all periods. Conversely, doctor-diagnosed and total hypertension (including those who are unaware) prevalence exhibited a slight decrease (1.4% and 3%, respectively), mirrored by reductions in population-wide mean systolic and diastolic blood pressure by 4.6mmHg and 1.9mmHg. These results suggest that, with the total population in England standing at 56.3 million in 2019, an estimated 15.8 million adults were within the obese BMI range, 6.5 million had diabetes and 17.6 million had hypertension. The obesity epidemic is likely fuelling the increase in diabetes prevalence. These findings underscore the importance of prioritising obesity reduction in public health initiatives, aiming to subsequently curb diabetes prevalence. Hypertension still remains a major CV risk factor, affecting almost one third of the adult population.