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23.6 million people—7.8 percent of the population—has diabetes.
Diabetes can lead to cardiovascular damage in a number of ways. These processes do not develop independently, as each may accelerate or worsen the others. This means that when people with diabetes develop for example a heart attack or stroke, the prognosis is worse than for people without diabetes because of the vicious cycle caused by the combined vascular abnormalities associated with diabetes. Indeed, cardiovascular disease is the leading cause of death in people with diabetes in developed countries.
All types of diabetes can lead to diseases within the heart and circulatory system. In many people with diabetes these different factors co-exist resulting in progressive damage to the heart and blood vessels.The two main processes which lead to cardiovascular disease are atherosclerosis and hypertension.
Atherosclerosis
Not only are people with diabetes at increased risk of developing atherosclerosis, but the process also tends to be accelerated, more severe and more widespread. This can cause severe clinical consequences in younger individuals. Since atherosclerosis damages the medium and large blood vessels, the term macroangiopathy Disease of the large blood vessels. Usually refers to the complications of diabetes resulting from atherosclerosis. is often used to indicate its presence in people with diabetes. Atherosclerosis in diabetes results from a complex interplay between a number of risk factors.
Hypertension
Hypertension is at least twice as common in people with diabetes as in the general population, and is also more frequent in people with impaired glucose tolerance. As well as atherosclerosis and hypertension there are other damaging effects which are specific to diabetes, microangiopathy Disease of the very small blood vessels. Usually refers to the chronic complications of diabetes resulting from damage to the capillaries.
Other abnormalities of blood vessels and autonomic neuropathy Disease of the nerves affecting mostly internal organs such as the bladder, the cardiovascular system, the digestive tract and the genital organs. These nerves are not under a person's conscious control and function automatically.. These processes worsen vascular function and therefore make the consequences of atherosclerosis/macroangiopathy and hypertension more difficult to withstand. In addition, they lead to other diabetic complications such as nephropathy and dysfunction..impotence The loss of a man’s ability to have an erect penis, often referred to as erectile dysfunction.
Autonomic neuropathy
Damage to the nerve supply of the internal organs of the body
- Problems with the pulse rate
- Postural fall in blood pressure
- Foot ulcers
- Impotence
- Gastro-intestinal dysfunction
Other blood vessel damage
Damage to the inner or outer lining of blood vessels
- Impaired regulation of blood flow
- Weakened vessel walls
- Aggravated microangiopathy and atherosclerosis/macroangiopathy
Microangiopathy
Microangiopathy refers to damage to the small blood vessels and capillaries, and is largely restricted to people with diabetes. It is a direct result of chronic hyperglycaemia. Other factors such as hypertension and dyslipidaemia also contribute. The direct causal link between hyperglycaemia and microangiopathy has been emphasized by a number of recent clinical trials, all of which show that the microangiopathic complications of diabetes are the most readily preventable with good glycaemic control. The largest of these studies are the Diabetes Control and Complications Trial (DCCT) in type 1 diabetes and the United Kingdom Prospective Diabetes Study (UKPDS) in type 2 diabetes.
Microangiopathy adversely affects capillary function leading to a shortage of supply of oxygen and nutrients to the tissues, and a leakage of proteins into the tissue spaces. Capillaries throughout the body are affected, but damage to the microcirculation of the eyes, kidneys and nerves is responsible for the major clinical manifestations - retinopathy, nephropathy, neuropathy and the diabetic foot.
Autonomic neuropathy
Diabetes can affect different components of the nervous system. One component, known as the autonomic nervous system, provides a nerve supply to the internal organs of the body, including the heart and blood vessels. Damage to this system is known as autonomic neuropathy.
Damage to the autonomic nervous system can be a direct result of chronic hyperglycaemia or, in turn, can follow microangiopathy involving the small vessels which supply blood to the nerves themselves, thereby causing a vicious cycle of nerve and blood vessel damage. Damage to the nerve supply of the heart affects the regulation of the pulse rate. In the blood vessels, manifestations such as a fall in blood pressure on standing or exercising can produce disabling symptoms and can affect measures aimed at treating hypertension.
Loss of the nerve supply to small blood vessels can also impair the regulation of blood flow. This is an important contributory factor to the development of diabetic foot ulcers A break in the skin or a deep sore that can occur in people with diabetes because of nerve and/or vessel damage to the foot.. Autonomic neuropathy is an important cause of impotence in men with diabetes. It can also affect the function of the bladder, stomach and intestine.
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