Diabetes complications
Until the discovery of insulin in the 1920s, type 1 diabetes mellitus was a fatal disease. These days, people with diabetes, both type 1 and type 2, can live long and active lives with correct treatment and management of their condition.
How do complications occur?
As people with diabetes live longer, we now know that complications can occur over time, even though their blood sugar levels may be controlled by regular insulin use or by taking tablets called oral hypoglycaemic (blood glucose lowering) medications. Complications are generally more common in people who have difficulty in maintaining their blood sugar at acceptable levels, a condition sometimes called ‘brittle diabetes’. As a result, doctors place great emphasis on maintaining blood glucose levels as close to normal as possible.
There are a number of important conditions that a person with diabetes can be at risk of developing.
Complications of diabetes
- Hyperglycaemia — excess sugar in the blood which can lead to coma.
- Hypoglycaemia — inadequate sugar in the blood, often due to an excessive insulin dose.
- Keto-acidosis — an excess of ketones (a type of acid) in the body. This is the result of poorly controlled (high) blood sugar levels. When there is not enough insulin available for the body to convert glucose (sugar) into energy, the body starts breaking down fat for energy. This process releases ketones as a waste product. If the levels of ketones are allowed to keep rising, the result can be coma and death.
- Eye complications, including diabetic retinopathy (damage to the retina), diabetic cataracts and glaucoma.
- Diabetic nephropathy (damage to the kidneys).
- Diabetic neuropathy (damage to the nerves).
- Conditions that may affect the legs and feet, especially poor circulation.
- Skin and mucous membrane complications, e.g. increased likelihood of bacterial and fungal skin infections.
- Hyperlipidaemia (high cholesterol and high triglyceride (fat) levels in the blood) and cardiovascular problems such as high blood pressure, hardening and clogging up of the arteries (atherosclerosis) and coronary artery disease.
Emergency complications of diabetes
- Diabetic keto-acidosis.
- Hypoglycaemic coma.
- Hyperglycaemic hyperosmolar coma.
Coronary artery disease
Hardening of the coronary arteries and the accumulation of fatty deposits in the walls of these arteries are complications of diabetes that may cause angina and heart attacks. This type of change in the coronary arteries is twice as common in people with diabetes than in those without diabetes, and affects both men and women equally.
Poor blood supply to the legs and feet
The arteries that supply blood in the legs may also become hardened and narrowed, causing poor circulation.
This often results in a condition called intermittent claudication (not being able to walk very far because of pain in the legs due to poor blood supply to the leg muscles), as well as poor wound healing and ulcers of the legs and feet and, occasionally, gangrene.
Last Reviewed: 28 May 2003
