Diabetes is a serious condition in which the body cannot maintain healthy blood glucose levels. Insulin, the hormone which regulates these levels, is no longer produced or is not produced in sufficient amounts by the body. People living with diabetes need to manage it daily, and it can have a significant impact on quality of life and health, including increased risk of cardiovascular disease (CVD), heart attack, stroke and blindness.
There are three main types of diabetes, plus a stage before diabetes called pre-diabetes.
Gestational diabetes occurs during pregnancy when the body cannot cope with the extra demand for insulin production, resulting in higher than normal blood glucose levels.
After the baby is born, gestational diabetes usually disappears, although some women may continue to have high blood glucose levels. There is also an increased risk of developing type 2 diabetes in the future for both mother and baby.
Gestational diabetes can occur in women with no known risk factors.
Type 1 diabetes
Type 1 diabetes is an auto-immune condition in which the pancreas produces little or no insulin. Those affected need to take insulin every day.
The exact cause of type 1 diabetes is not known, but there is a strong genetic link. There is no known link to modifiable lifestyle factors such as diet and exercise, but maintaining a healthy lifestyle can help to manage the condition.
Type 1 diabetes cannot be prevented, and there is no cure.
Type 2 diabetes
In type 2 diabetes, the body becomes resistant to the normal effects of insulin and/or gradually becomes unable to produce enough insulin. This develops over a long period of time. Until recently, this type of diabetes was seen only in adults, but it is now also occurring in children.
The cause of type 2 diabetes is not known. However, there is a strong genetic link, and it is also linked to modifiable lifestyle risk factors such as excess body weight and physical inactivity.
While many people with type 2 diabetes show no symptoms, symptoms can include:
- Frequent or excess thirst
- Passing more urine
- Feeling tired and lacking energy
- Feeling hungry frequently
- Having cuts that heal slowly
- Itching, skin infections
- Blurred vision
- Unexplained weight changes
- Headaches and feeling dizzy
In the early stages, type 2 diabetes can often be managed with healthy eating and regular physical activity. Taking medication or insulin as soon as required can also result in fewer long-term complications.
In pre-diabetes, blood sugar levels are higher than the normal range, but not enough to be considered diabetes. People with pre-diabetes are at higher risk of developing type 2 diabetes and CVD later in life.
More than one in four New Zealand adults have pre-diabetes.1 People with pre-diabetes have an increased risk of developing both diabetes and CVD, but this risk can be decreased through lifestyle changes such as losing weight, increased physical activity and eating a healthy diet.
It is estimated that more than 200,000 people in New Zealand have diabetes. In the Māori and Pacific populations, the prevalence of diabetes is around three times higher than among other New Zealanders.2
Diabetes is a major risk factor for CVD. People living with type 2 diabetes are over twice as likely to develop CVD, with the number one cause of death for people with type 2 diabetes being CVD.3, 4 One of these cardiovascular conditions is peripheral artery disease (PAD), which places sufferers at risk of limb amputation.
Type 2 diabetes can occur in anyone of any age or gender, but people are at a higher risk of developing it if they:
- have a family history of diabetes
- are overweight
- have high blood pressure
- are over 55 years of age
- are from a Māori or Pacific background, or are from an Indian subcontinent or Chinese cultural background.
There are also around 100,000 people in New Zealand living with undiagnosed diabetes.2
What is HRI doing?
HRI is tackling the urgent issue of rising rates of diabetes and cardiovascular disease from various research angles.
The Cardiometabolic Disease Group at HRI aims to develop better diagnostic markers, predictors and novel therapies for metabolic disorders such as diabetes, to enable early detection and better treatment.
The Vascular Complications Group aims to understand the pathogenesis of blood vessel disease in diabetes, and using this knowledge, identify new strategies to improve function and reduce the burden of disease.
The Thrombosis Group has made the fundamental discovery as to why patients with diabetes are at more risk of developing lethal blood clots. They are currently examining ways to prevent thrombosis in diabetics.
The Cardiovascular Neuroscience Group studies the brain changes that occur in obstructive sleep apnoea and how this is involved in the pathogenesis of diabetes in OSA patients.
Our findings may offer hope, especially to diabetic patients who are resistant to conventional anti-clotting drugs. Targeting biomechanical pathways may also have the advantage of preventing deadly clots without bleeding side effects. Since diabetes represents the biggest threat to the Australian health system, our discovery sheds light on protecting vulnerable diabetic individuals from heart diseases.
- Coppell KJ, Mann JI, Williams SM, et al. 2013. Prevalence of diagnosed and undiagnosed diabetes and pre-diabetes in New Zealand: findings from the 2008/09 Adult Nutrition Survey. New Zealand Medical Journal 126(1370):23-42.
- NZ Ministry of Health; About Diabetes https://www.health.govt.nz/our-work/diseases-and-conditions/diabetes/about-diabetes
- Haffner SM et al; Mortality from coronary heart disease in subjects with type 2 diabetes and in nondiabetic subjects with and without prior myocardial infarction. N Engl J Med 1998; 339:229-234.
- Australian Institute of Health and Welfare; Deaths among people with diabetes in Australia, 2009–2014.