Complications of Diabetes

Diabetes mellitus occurs when the pancreas (an endocrine gland in the abdomen) cannot make enough insulin to satisfy the demands of the body. We currently recognize two types of diabetes. Type 1 is due to destruction of the cells in the pancreas that make insulin. These individuals, usually, must take insulin injections for the rest of their life. Type 1 generally occurs early in life and is of sudden onset. This type of diabetes happens at a level rate and does not seem to be increasing. In our country, only 1 of 25 people with diabetes has type 1 diabetes.

Type 2 diabetes is much more common than type 1. We now have about 25 million people in the US with type 2 diabetes, and the number of people affected is rising rapidly. Type 2 diabetes seems to have a more gradual onset, and is often treated with pills early in its course. This type of diabetes seems to be tied to the epidemic of overweight and obesity around the world. We used to think of it as starting at an older age, but now it is more frequently diagnosed in younger people, including children and teenagers. The US has the third largest number of people in the world with diabetes, surpassed only by India and China. The increased incidence of diabetes is a worldwide epidemic, and no country is spared.

Both types of diabetes are associated with similar complications. They are generally split into microvascular and macrovascular complications. Microvascular means small blood vessels such as the blood vessels in the eye and the kidney. Macrovascular means large blood vessels such as the blood vessels of the heart and the brain, as well as the large blood vessels of the legs. We’ll start out with the small blood vessels.

Let’s start with diabetic retinopathy, which refers to disease of the small blood vessels of the retina caused by diabetes. Diabetic retinopathy usually starts out with small areas of bleeding in the back of the eye (the retina). The retina is the area responsible for our eyesight, and if it becomes seriously damaged eyesight becomes impaired. The result of untreated retinopathy can be blindness. Diabetic retinopathy is the leading cause of blindness in adults. Early diagnosis and treatment can prevent blindness from occurring. Everybody with diabetes should have what we call a dilated eye exam once a year. This means that the pupils are dilated with eye drops and the eye doctor can get a good look at the retina in the back of the eye. If there are early changes of retinal disease, the person can be treated. Early treatment usually consists of laser therapy to the retina. Tight control of diabetes will often keep the retinopathy from getting worse, and may even reverse the effects.

Diabetic nephropathy is another microvascular complication that refers to disease of the small blood vessels of the kidney. If nephropathy continues to progress, it can ultimately lead to kidney failure, which may have to be treated by dialysis or kidney transplantation. The early stages of nephropathy can be picked up by laboratory testing of the blood and urine. Medicines are available to prevent the kidney disease from getting worse. Tight diabetes control also helps. Diabetes, however, is the leading cause of kidney failure leading to dialysis in the adult population. Renal failure is serious and can dramatically worsen quality of life of the person with diabetes, and also shorten the lifespan of the person who has it. Once again, it is important to pick up kidney disease early and institute treatment as soon as possible. Kidney disease also makes it difficult to treat the person for other diseases because kidney failure can change the action of many drugs that we prescribe.

Diabetic neuropathy refers to a complication involving the nerves of the body, perhaps by interfering with the small blood vessels supplying these nerves. The feet are usually the first to suffer and common symptoms include numbness, pins and needles feelings, pain, and eventually loss of sensation. With severe neuropathy of the feet, one cannot feel cold, heat or even touch. Under these circumstances, it is easy to produce damage to the feet. For example, if you had a nail in your shoe and couldn’t feel it, you could damage your feet.