Bill Thurston was playing golf when he had his first heart attack at the age of 60.

He recalls experiencing "uncontrollable heavy breathing" but had no idea what was causing it and decided to cut his game short and go home.

"Luckily I was playing with a mate who had had a heart bypass who dragged me to A&E," he says.

When the 79-year-old was diagnosed with type 1 diabetes doctors warned him he was more at risk of heart disease in later life but then 23, he "didn't take much notice of it."

"They talked about the long term complications like diabetic retinopathy, where your blood vessels burst behind the eye, and the increased danger of heart disease and kidney disease," he says.

"Eventually one by one they caught up with me."

People with diabetes - both type 1 and 2 - are up to three times likely to develop a heart condition than the general population.

However many will not experience any of the typical heart attack symptoms such as crushing chest pain and shortness of breath.

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Now, Scots scientists are hoping a major new project will help untangle the link between diabetes and so-called 'silent' heart attacks to help prevent more happening.

Diabetes damages blood vessels, making them easier to become clogged or blocked. 

While the link with type one is well recognised, experts say many patients with the genetic form of the condition are not aware of the risks.

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"There is a huge additional burden in heart disease in people with diabetes," said Professor Ewan Pearson, Professor of Diabetic Medicine at the University of Dundee.

"I think most people would assume it's type two diabetes because that is the type that is more associated with overweight and an unhealthy lifestyle but actually - depending on whether you look at men or women and the age - there is a two to three times risk of heart disease in type 1 as well.

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"We know that the higher the sugar levels the greater the impact on heart disease.

"A person with diabetes can have a heart attack but not know about it. You think of a heart attack as crushing chest pain and feeling extremely ill but people with diabetes can have silent heart attacks.

"They may go completely unnoticed. If it's not immediately obvious, there is a delay in treatment them and their heart will be being damaged and sometimes there is irreparable damage."

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Type 1 diabetes occurs when the immune system attacks and destroys the insulin-producing beta cells of the pancreas and blood glucose (sugar) levels become too high.

Scientists think genes and environmental factors, such as viruses, that might trigger the disease. Obesity and an inactive lifestyle are two of the most common causes of type 2.

Prof Pearson says there is a wealth of data available in the NHS that is "not being used properly" that could help answer key questions including why, for example, some people who are overweight do not develop type 2.

The Diabetes Data Science Catalyst - a partnership between the British Heart Foundation (BHF), Diabetes UK and Health Data Research UK - aims to do this by giving researchers ethical access to this "big data".

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"The NHS is unique in the world in that it has one universal healthcare provider and as such we have joined up data and a huge opportunity to understand who is most at risk and how can we prevent diabetes and heart disease", says Prof Pearson, who is , Associate Director of the BHF Data Science Centre.

He says maintaining healthy cholesterol, blood pressure and sugar levels is "really important".

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Mr Thurston, who lives in Broughty Ferry with his wife Margaret, was diagnosed with type 1 diabetes in 1967 when he was 23.

"One minute I was playing football at 11 stone 4lbs, two or three months later I was less than six-and-a-half stone," he said.

"I lost huge amounts of weight and had a massive thirst. I was drinking 20 or 30 pints of water a day but was still thinking there was nothing wrong with me.

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"I went to the GP and was taken straight to hospital and put on insulin."

He had a second heart attack in 2013, when he was 70 and this time the symptoms were "more dramatic" and necessitated a heart bypass.

"I believe it's all to do with the increased sugar levels because the control of your sugar is never accurate. It's always a bit hit and miss. For the first 25 years of my diabetic career I had no means of testing my own blood - even the finger pricking machines hadn't been invented.

"These days I've got one of those Libre Sensors that Theresa May has. If I had had one of those 50 years ago I probably wouldn't have had a heart bypass."

Mr Thurston's father died of a heart attack when he was 68 and while he didn't have type 1 diabetes, his son thinks he may have had the genetic defect that can lead to some people developing the condition.

He said: "None of the tablets that I am on to improve the heart's function were available to him so he died at 68 and I am still going fairly strong at 79."