Women with diabetes are more likely to get heart failure than men because they don't manage the condition as well, scientists have said.
This difference in risk was particularly high for type 1 diabetics, with a 47 percent higher chance of heart failure in women than men.
Women with type 2 diabetes, meanwhile, had a risk nine per cent higher than men with the same condition, the study of 12million people found.
It is already known that diabetics are more likely to get heart disease because high blood sugar can cause blockages in blood vessels which become damaged over time.
Scientists suggest women are more likely to suffer because their diabetes isn't being spotted early enough and they don't get the same level of care.
Women with diabetes are more likely to get heart failure than men because they don't manage the condition as well, scientists have said (stock image)
Researchers from the George Institute for Global Health, in Oxford, published their findings in the journal of the European Association for the Study of Diabetes.
Lead author Dr Toshiaki Ohkuma said: 'It is already known that diabetes puts you at greater risk of developing heart failure but what our study shows for the first time is that women are at far greater risk – for both type 1 and type 2 diabetes.'
There are 3.8million people diagnosed with diabetes in the UK, of which about 90 per cent have type 2 diabetes.
If trends continue, it's estimated that more than five million people will have diabetes in the UK by 2025.
Globally the prevalence of diabetes is soaring, from 108million patients in 1980 to 422million in 2014, according to the World Health Organization.
Diabetes is associated with both an increased risk of heart failure and an increased risk of death following diagnosis.
Heart failure is the second most common initial presentation of cardiovascular disease in people with type 2 diabetes - more common than heart attack or stroke.
WHY ARE PEOPLE WITH DIABETES AT HIGHER RISK OF HEART FAILURE?
After we eat, we begin to digest foods and break carbohydrates down into glucose.
In people who don't have diabetes, insulin is released by their pancreas which acts as a signal for cells around their body to absorb the glucose and use it as fuel for energy.
People with diabetes have high levels of glucose in their bloodstream because they cannot make enough insulin so their body doesn't soak up the sugar.
If there are high blood sugar levels for a long of time, even slightly higher than is normal, the blood blood vessels can start to get damaged and this can lead to serious heart complications.
The body can't use all the sugar properly, so more of it sticks to the red blood cells and builds up in the blood.
This build-up can block and damage the vessels carrying blood to and from the heart, reducing blood flow and thus starving the heart of oxygen and nutrients.
High levels of glucose in your blood can also physically damage the walls of the arteries, and make them more likely to develop fatty deposits which restrict the vessels.
Diabetics must keep as close as possible to their target HbA1c level – an average measure of blood sugar over two to three months – to protect their blood vessels and in turn their heart. Even mildly raised blood sugar levels can, over time, put a diabetic at higher risk.
Data from 14 studies, with 47 groups and more 12million individuals from Australia, UK, Italy, Sweden, Canada, Japan, China, Taiwan and Korea was analysed by the research team.
Researchers found type 1 diabetes was associated with a 5.15 times higher risk of heart failure in women, and a 3.47 times higher risk in men.
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.
Women are at a five-fold increase of heart failure compared to women without diabetes.
The study authors offered a number of explanations.
Study co-author Dr Sanne Peters said: 'Women were reported to have two years' longer duration of pre-diabetes than men and this increased duration may be associated with greater excess risk.
'Some major concerns are that women are also being under-treated for diabetes, are not taking the same levels of medications as men and are less likely to receive intensive care.'
Excess risk of coronary heart disease associated with diabetes has previously been shown to be greater in women.
This could be due to women historically having poorer blood sugar control than men.
Another possibility is that under-treatment for women with diabetes may contribute to the development of diabetic cardiomyopathy – a disease of the heart muscle which causes it to become thick or rigid.
The authors said: 'In conclusion, the excess risk of heart failure following diagnosis of diabetes is significantly greater in women than men.
'[This highlights] the importance of intensive prevention and treatment of diabetes for women as well as men.
'Further research is required to understand the mechanisms underpinning the excess risk of heart failure conferred by diabetes - particularly type 1 - in women and to reduce the burden associated with diabetes in both sexes.'
Type 1 diabetes, of which the cause is unknown, and type 2 diabetes, which is largely preventable and treated with a healthy lifestyle, are serious health conditions.
If left unmanaged they can lead to kidney failure, eye problems, stroke and heart disease, as well as amputations.
Type 2 usually affects adults over 40 and until 20 years ago had never been seen in children in the UK.
However Britain’s spiralling obesity crisis means growing numbers of young people are at risk.
The George Institute has been leading gender specific research and has already shown women with diabetes have a significantly greater excess risk of stroke and coronary heart disease, as well as complications of dementia and cancer, than men.