While insulin allows a person with type 1 diabetes to stay alive, it does not cure the disease, nor does it prevent the development of serious complications, which can be many and varied. High blood sugar levels eventually damage blood vessels, nerves, and organ systems in the body. Among the potential complications of type 1 diabetes are:
Cardiovascular disease, a range of blood vessel system diseases that includes both stroke and heart attack, is the major cause of death in people with diabetes. The two most common types of cardiovascular disease are coronary heart disease, caused by fatty deposits in the arteries that feed the heart, and hypertension, or high blood pressure. Research shows that people with diabetes are more likely to have high cholesterol and hypertension, both of which cause damage to the cells lining the artery walls. Researchers think high blood glucose contributes to both of these conditions.
Hypoglycemia, low blood sugar, is a dangerous condition for people with diabetes. It can be triggered by not eating often enough, eating too little food, too much physical activity without eating, or too much insulin. People with diabetes can usually tell when their blood sugar is low. But the more episodes of hypoglycemia you have, the harder it gets for your body to detect the next episode. In severe forms, hypoglycemia can lead to unconsciousness or even death. For patients with type 1 diabetes, fear of hypoglycemia is a major obstacle to maintaining tight blood glucose control.
Diabetic kidney disease, also known as diabetic nephropathy, is one of the most common and most devastating complications of diabetes. It is a slow deterioration of the kidneys and kidney function which, in severe cases, can eventually result in kidney failure, also known as end-stage renal disease, or ESRD. About one third of people with type 1 diabetes develop nephropathy.
Neuropathy, or nerve damage, affects more than 60 percent of people with type 1 diabetes. The impact of nerve damage can range from slight inconvenience to major disability and even death. Diabetic neuropathy leads to loss of feeling and sometimes pain and weakness in the feet, legs, hands, and arms, and is the most common cause of amputations not caused by accident in the United States. In one type of neuropathy, known as autonomic neuropathy, high glucose levels injure the autonomic nervous system, which controls bodily functions such as breathing, circulation, urination, sexual function, temperature regulation, and digestion. Autonomic neuropathy may result in various types of digestive problems, diarrhea, erectile dysfunction, a rapid heartbeat, and low blood pressure.
Diabetic retinopathy is the most common and serious eye-related complication of diabetes. It is a progressive disease that destroys small blood vessels in the retina, eventually causing vision problems. In its most advanced form (known as “proliferative retinopathy”) it can cause blindness. Nearly all people with type 1 diabetes show some symptoms of diabetic retinopathy, usually after about 20 years of living with diabetes; approximately 20 to 30 percent of them develop the advanced form.