They found that type 1 diabetes was associated with a 47% excess risk of heart failure in women compared to men, whilst type 2 diabetes has a 9% excess risk of heart failure for women than men.
“The excess risk of heart failure associated with diabetes is significantly greater in women with diabetes than in men”
The study, published in the journal Diabetologia, was carried out by teams at the University of New South Wales and the University of Oxford.
The researchers noted that it was already recognised that diabetes and heart failure were conditions that often occurred together.
They also highlighted that accumulating evidence suggested that there were “considerable” sex differences in the increased risk of a range of cardiovascular diseases associated with diabetes.
Previous analyses had shown diabetes conferred a greater excess risk of coronary heart disease and stroke, as well as other non-cardiovascular complications including dementia and cancer, in women.
The new study specifically examined possible sex differences in the excess risk of heart failure associated with diabetes, by looking at a range of existing studies that were deemed relevant.
The study pooled the sex-specific relative risks and the women to men ratio of relative risks for heart failure, either fatal or non-fatal, comparing individuals with diabetes to those without the condition.
Of 5,991 articles originally identified, 14 studies provided useable data for sex differences in the association between diabetes and the risk of heart failure.
Two of these included data on type 1 diabetes, while data on type 2 diabetes and heart failure were available from 13 studies.
Type 1 diabetes was linked with a 5.15 times higher risk of heart failure in women, and a 3.47 times higher risk in men – meaning a 47% excess relative risk of heart failure for women compared to men.
Meanwhile, type 2 diabetes was associated with a 1.95 times higher risk of heart failure in women, and a 1.74 times higher risk in men – meaning a 9% excess relative risk for women versus men.
The study authors stated: “The excess risk of heart failure associated with diabetes is significantly greater in women with diabetes than in men with diabetes.”
The authors suggested several potential explanations for the increased excess risk of heart failure in women with diabetes.
They noted that diabetes may mean a higher CHD risk in women or that sex differences in diabetes management could be a factor, as historically women have had poorer blood glucose control.
Another possibility is that under-treatment for women with diabetes may contribute to the development of diabetic cardiomyopathy, suggested the authors.
Yet another option for the difference concerns sex variation in prolonged high blood glucose levels prior to full diabetes, known as “prediabetes”, which can be up to two years longer in females.
Finally, other cardiovascular risk factors, again reported to be higher in women with diabetes than men, may account for the greater excess risk in women, said the researchers.
They stated that their findings highlighted “the importance of intensive prevention and treatment of diabetes for women as well as men”.
They also stressed the need for further research to understand the mechanisms underpinning the excess risk in women they had identified, particularly for type 1 diabetes.