Complications of diabetes

The complications of diabetes can be serious, but if you make appropriate lifestyle changes and pay attention to your blood glucose control, you can substantially reduce the risk of these complications. If diabetes is left undiagnosed or unchecked for too long, it can lead to serious and often life threatening complications including:

  • Heart disease
  • Kidney disease
  • Blindness
  • Limb amputation
  • Erectile dysfunction
  • Persistent infections

You can find out more about possible complications by watching this video or  by reading the information below.

It’s important to note that some of the complications are specific to your type of diabetes – type 1, type 2 or gestational diabetes. So take note of this and if you have questions talk to your doctor, diabetes team or call our Helpline on 1300 342 238.


Hypoglycaemia (also called ‘a hypo’) is when your blood glucose level has dropped too low. While hypoglycaemia can be experienced by people taking certain tablets for their diabetes, it is more common in people who inject insulin for type 1 diabetes. It is generally not a problem for people with type 2 diabetes who can manage their diabetes through a healthy eating plan and physical activity, but it is still possible.


Hyperglycaemia (also called a ‘hyper’) means high blood glucose levels. It’s possible for your blood glucose levels to be high and for you to not be aware of it, because many people do not experience the symptoms of hyperglycaemia.

Kidney disease

Your kidneys help to clean your blood. They remove waste from the blood and pass it out of the body as urine. Over time, diabetes can cause damage to your kidneys (a condition called diabetic nephropathy). You won’t notice damage to your kidneys until it’s quite advanced, so it’s important that you have the recommended tests to pick up any problems early. The risk of developing kidney problems is reduced by managing your blood glucose levels, having regular kidney and blood pressure checks and leading a healthy lifestyle. Finding out about kidney damage early is simple and painless. Early treatment can prevent kidney damage and serious complications.

Nerve damage and lower limb complications

Progressive damage to your nervous system caused by diabetes is called diabetic neuropathy. It can lead to a loss of feeling in your hands and feet. Reduced circulation from high blood glucose can affect normal wound healing in your extremities. That means minor damage can linger and develop into permanent injury. Personal daily foot checks and thorough annual foot examinations conducted by your doctor or podiatrist will help to reduce your risk of lower limb complications.

Heart disease and stroke

People with diabetes have increased risk of heart disease and stroke due to raised blood glucose levels (BGLs), in association with high blood pressure and cholesterol.

Eye disease (diabetic retinopathy)

Diabetes can damage the back of the eye and affect your vision. The development of diabetic retinopathy is strongly related to the length of time you’ve had diabetes and your degree of blood glucose control. Regular checks and treatment can prevent serious eye problems and blindness.

Oral health

Dental problems are more common in people with diabetes, including:

  • Gum inflammation (gingivitis)
  • Infection and inflammation of the ligaments and bone that support the teeth (periodontitis)
  • Tooth decay (dental caries)
  • Dry mouth (xerostomia)
  • Fungal infections (oral thrush)
  • Disturbances in taste

Oral problems can occur in people with diabetes for a number of different reasons. It’s important to visit your dentist regularly and tell them about your diabetes. If you have diabetes and persistent high blood glucose levels you’re more likely to have dental problems.

Sexual health

While most people with diabetes are able to lead completely normal sex lives, diabetes may contribute to sexual problems for some people.


We don’t know exactly why hearing loss is more common among people with diabetes. Some researchers believe prolonged high blood glucose levels may lead to hearing loss by affecting the supply of blood or oxygen to the tiny nerves and blood vessels of the inner ear. Over time, the nerves and blood vessels become damaged, affecting your ability to hear.

Coeliac disease

Type 1 diabetes and coeliac disease are both described as autoimmune diseases, meaning that your immune system is attacking parts of your body. While the causes of both coeliac disease and type 1 diabetes are not fully known, there is a relationship between the two. Between 4 and 10 per cent of people with type 1 diabetes also have coeliac disease.

Diabetic ketoacidosis (DKA)

Consistently high blood glucose levels can lead to a condition called diabetic ketoacidosis. This happens when a severe lack of insulin means your body cannot use glucose for energy and it starts to break down other body tissue as an alternative energy source. Ketones are the by-product of this process.

Ketones are poisonous chemicals which build up and, if left unchecked, will cause the body to become acidic, hence the name ‘acidosis’. DKA generally develops over 24 hours but can develop more quickly, particularly in young children. DKA develops when blood glucose levels are extremely high, often as a result of illness. DKA can develop rapidly and should be treated as a medical emergency at hospital.

Depression, distress and burnout

The demands of managing type 1 diabetes are considerable. Diabetes burn-out, diabetes distress and diabetes depression are very real problems you may experience. It’s important that you don’t ignore your emotional wellbeing. These factsheets have been developed to provide you with useful tips to avoid these complications:

Diabetes NSW & ACT also has a Psychologist on Call service. Our Psychologist, is available for confidential and informal phone discussions to help you develop strategies to manage your diabetes and get you back to a happier, more fulfilling life. If you would like to access this service please call our Helpline on 1300 342 238 to make an appointment.


If you repeatedly inject insulin into the same place on your body, you can develop a build-up of fatty tissue under the skin which is known as lipohypertrophy.

Persistent infections

Ongoing infections that don’t appear to heal can lead to more serious consequences for people living with type 1 diabetes. If you get an infection, it is important that you contact your doctor or call Diabetes NSW & ACT on 1300 342 238 and ask to speak to a diabetes educator.

Need help or advice?

Speak to a member of your diabetes team or contact the NDSS Helpline on 1300 136 588 and ask to speak to a Diabetes Educator.

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