New research by the University of Glasgow shows that high blood sugar levels do not put patients at high risk for heart disease.
The research, led by professor Naveed Sattar of the University’s Institute of Cardiovascular and Medical Sciences, followed over 370,000 patients from the UK Biobank over two to three months, testing the patients’ average blood glucose (sugar) levels. As screenings for diabetes risk often include blood sugar level measurements, researchers aimed to verify whether knowing blood sugar levels could improve cardiovascular disease risk assessment.
The study found that "on average [those at higher risk of diabetes] were around 10kg heavier, and their blood pressure was already six units higher.” Many of the study participants also smoked, which placed them at higher risk of cardiovascular diseases. The findings suggest that these factors put patients at greater risk well before elevated blood sugar level comes into play.
This means the risk for heart disease is not dependent on elevated sugar levels even though those at risk for diabetes have about an 80% greater chance of developing heart disease compared to those with average blood sugar levels.
The study also found that patients at a higher risk for diabetes had a higher risk of heart disease. Diabetes risk factors include obesity, high blood pressure and high cholesterol. When testing for heart disease, doctors often check these risk factors.
However, a traditionally held risk factor, blood sugar measurement, was not a reliable indicator of cardiovascular disease risk, the study showed.
Sattar said: “Doctors, therefore, should make sure [patients at risk] are properly checked for all risk factors as then the patient can better know all their risks and be more motivated to make lifestyle changes which may lessen all these risks.”
The NHS dietary recommendation is still to eat a low-fat, high-fibre diet which includes whole grains and fresh fruit and vegetables.
Despite these findings, healthy eating, exercise, and a limit on sugar intake is still recommended by prevailing medical science, and everyone should also be informed of other established heart disease risk factors like age, blood pressure, cholesterol levels, smoking and BMI.