It has long been claimed that there is a link between stroke and diabetes, with charity Stroke Association noting that the condition almost doubles your risk of having a stroke.
There are two types of diabetes: type one, where the body’s immune system attacks and destroys the cells that produce insulin, and type two, where the body either doesn’t produce enough insulin or cells do not react. According to the NHS, around 90 per cent of all adults with diabetes in the UK will suffer from type two.
Meanwhile a stroke is a condition in which blood supply to the brain is affected. Diabetes UK states that people with diabetes have up to a five times higher risk of cardiovascular disease, which can lead to heart attacks and stroke, and statistically have a higher risk of dying from these conditions than the general population.
But how exactly are the two connected – and most importantly, what can diabetes sufferers do to minimise their risk? Stroke Rehab Times examines the link.
How can diabetes lead to stroke?
According to Healthline, diabetes affects the body’s ability to create insulin or use it properly, and since insulin plays an important role in pulling glucose into cells from the bloodstream, people with diabetes are often left with too much sugar in their blood.
Over time, this excess sugar can contribute to the build-up of clots or fat deposits inside vessels that supply blood to the neck and brain – a process known as atherosclerosis.
If this build-up grows, it can cause a narrowing of the blood vessel wall, or even a complete blockage. When blood flow to the brain stops for any reason, a stroke occurs.
High blood pressure can also be attributed to increasing the risk of stroke in patients with diabetes. As a contributing factor in around half of all strokes, it is the single biggest risk for the condition. Plus, it’s twice as likely to strike a person with diabetes than a person without.
Diabetes UK has also warned of the risks of high cholesterol (blood fats) in diabetes patients. It says: “If your cholesterol is too high, then the extra fat in your blood sticks to the walls of your blood vessels. Over time, this fat hardens and is known as plaque.
“Hard plaque can block up the blood vessels, which makes the space narrower and leaves less room for blood to flow. In the narrower space, blood flow slows down and causes some of the blood cells to group together and clot.”
Similarly to the process with high blood sugar levels, when a blood clot breaks away, it can partially or completely block arteries and veins, which can in turn starve the brain of oxygen and nutrients, causing a stroke.
The charity therefore advises that by looking after blood sugar levels, blood pressure and cholesterol – and undertaking regular checks of these – diabetes patients can protect themselves from complications such as stroke.
What does the recent research say?
A recent study from Sweden has backed up the claims above, stating that insulin resistance – a key feature of type two diabetes – is associated with a higher risk of stroke.
The study of more than 100,000 people with the condition found that the higher the insulin resistance, the greater the stroke risk.
Insulin resistance – which occurs when cells don’t respond properly to insulin and cannot easily take up glucose from the blood – is a key feature of diabetes, and levels vary from patient to patient. The researchers used estimated glucose disposal rate (eGDR) as a measure of this resistance during the study.
Patients were followed up for an average of 5.6 years, during which four per cent had a stroke. Analysis revealed that those with the lowest insulin resistance – the highest eGDR – were found to be 40 per cent less likely to have a stroke.
Higher insulin resistance was also linked to a higher risk of death after a stroke, with those with lower resistance 28 per cent less likely to die during the follow-up period.
Meanwhile, research recently published in medical journal ‘Neurology’ has found that for people with diabetes who have already had one stroke, there may be ideal blood sugar levels to lower the risk of a second occurence.
Study author Moon-Ku Han, of Seoul National University College of Medicine in Korea, said: “We know that having diabetes may be associated with an increased risk of having a first stroke.
“But our results indicate that there is an optimal blood sugar level that may start to minimise the risk of having another stroke, heart attack or other vascular problems, and it’s right in the 6.8 to seven per cent range.”
How can I reduce the risk?
The good news for diabetes sufferers is that steps can be taken to minimise the risk of stroke.
Diabetes UK – one of the country’s leading charities – offers the following advice to reduce your chances of a stroke occurring:
- Get your HbA1c (average blood sugar levels), blood pressure and blood cholesterol measured at least once a year and keep in your target range
- Don’t smoke, as it makes it harder for blood to flow around the body
- Eat a healthy, balanced diet
- Be physically active
More information can be found on the charity’s website here.
Stroke Association also offers guidance to reduce the risk here.
