Analysis of data from 427,435 people shows even below the threshold for diabetes people with high blood sugar have increased risk of heart and circulation problems with women at greater risk than men
Men and women with raised blood sugar levels have 30-50% greater risk of developing cardiovascular diseases even when these levels are below the threshold for diabetes, a new study has shown.
The study, led by researchers at the London School of Hygiene & Tropical Medicine (LSHTM) and University College London (UCL), also found that, among people diagnosed with diabetes, women's higher relative risk of developing any cardiovascular disease (CVD) than men disappeared once modifiable factors such as body measurements and medication use were taken into account.
The researchers discovered evidence that for blood sugar levels within the 'normal' range, it was a case of 'the lower the better' in protecting against CVDs. Compared to people with normal blood sugar levels, those with the lowest levels had a 10% lower risk of developing any form of CVD. On the other hand, men with raised blood sugar below the threshold for diabetes had a 30% greater risk of developing CVDs and women with raised blood sugar below the threshold for diabetes had between 30-50% greater risk of developing CVDs. The risks were as much as doubled in those with diagnosed diabetes.
The study analysed UK Biobank data from 427,435 UK individuals (54.2% women, 45.8% men) across the glycaemic spectrum, including people with blood sugar levels within a 'normal' range, those with prediabetes, and those with diabetes. The research is published in The Lancet Regional Health - Europe.
After adjusting for age, the researchers found that both men and women with moderately elevated blood sugar levels below the threshold for diabetes were at increased risk for any CVD, with relative increases higher for women than men.
Differences in the relative risk of developing CVDs between men and women largely disappeared after the researchers accounted for measures of obesity and the use of antihypertensive and statin therapies.
The research uncovered differences in the use of antihypertensive and statin therapies between men and women, with more men than women on these medications. It suggests that women are not prescribed these preventative medications at the same rate as men with similar blood sugar levels. The researchers say a study focusing on the factors behind this 'prescribing gap' is needed.
Lead author Dr Christopher Rentsch from LSHTM said: "This work represents a meaningful step forward from decades of research on diabetes and heart disease. We quantified differences in the risk of heart disease between men and women across the full range of blood sugar levels. What we discovered is that those risks are not only confined to people with diagnosed diabetes, that men and women with prediabetes are also significantly affected. Our team also uncovered compelling evidence that within the 'normal' blood sugar range, a lower level appears to be better for protecting against heart disease."
Senior author Professor Krishnan Bhaskaran from LSHTM said: "Our results suggest that the increased risks seen in both men and women could be mitigated through modifiable factors, including weight reduction strategies and greater use of antihypertensive and statin medications. This is an important new insight that should help guide future public health strategies."
Limitations of the study include that UK Biobank participants are healthier than the overall UK population, and that lifestyle data were self-reported.
The researchers conducted an observational cohort study using data from UK Biobank. The final analysis included 427,435 participants, including 195,752 (45.8%) men and 231,683 (54.2%) women aged 40-69 recruited between 2006 and 2010 across England, Scotland, and Wales, and followed through to 2021.
The researchers categorised participants at standard clinical cut-off points: low-normal (
Publication
Christopher T. Rentsch, Victoria Garfield, Rohini Mathur, Sophie V. Eastwood, Liam Smeeth, Nish Chaturvedi, and Krishnan Bhaskaran, Sex-specific risks for cardiovascular disease across the glycaemic spectrum: a population-based cohort study using the UK Biobank. The Lancet Regional Health - Europe. doi.org/10.1016/j.lanepe.2023.100693
