Insulin
Most people with type 1 diabetes take insulin by injecting it with a needle and syringe or an insulin pen. The goal is to mimic normal insulin release as closely as possible.
People without diabetes have a low level of insulin available in the blood most of the time. This is a background, or basal, level of insulin. After meals, a bolus (extra dose) of insulin is released, just enough to clear the glucose in the blood after eating.
To imitate this sequence, you can develop a regular schedule of insulin injections using different forms of insulin. Read on in chapter 13 for a lot more about insulin and insulin plans. Other people use insulin pumps to dispense insulin at a steady background, or basal, rate and to provide extra insulin to cover meals. More about insulin pumps can be found in chapter 13.
Although today’s insulin pumps are worn externally, researchers are developing and testing pumps that are placed inside the body. Ideally, the pump would sense the amount of glucose in the blood and deliver the right amount of insulin, as needed. These pumps are called closed-loop systems.
Your type of insulin therapy should relate directly to your health and your lifestyle choices. Your chosen therapy may aim to keep your blood glucose levels from shooting too high after meals or falling too low between meals. Or your therapy may aim to keep after-meal blood glucose levels as close as possible to those of someone without diabetes.
The food you eat and the exercise you get go hand in hand with your insulin therapy. Of course, healthy eating and regular exercise are a part of everyone’s healthy living plan. But for you, knowing how these two daily features move your blood glucose level up and down is essential.
To know how much insulin you’ll need to have, it helps to know:
• Your current blood glucose level (you know this by blood glucose testing).
• What you plan to eat (so you can estimate how much your blood glucose will increase).
• What physical activities you plan to do.
There is more information about insulin therapy and different insulin plans in chapter 13, and more about healthy eating in chapter 10. Read about physical activity and exercise for people with type 1 diabetes in chapter 11.
Pancreas Transplants
So far, the only way to treat type 1 diabetes is to give the body another source of insulin. Usually, this is done through insulin injections. However, new experimental approaches also show some promise.
Some patients with type 1 diabetes have experienced positive results from pancreas transplants. Typically, part or all of a new pancreas is surgically implanted. The old pancreas is left alone; it still makes digestive enzymes, even though it doesn’t make insulin. Most organs are obtained from someone who has died but decided to be an organ donor.
A transplant of the pancreas is usually reserved for those with serious complications. Pancreas transplants are most often done when a patient also receives a new kidney. The pancreas transplant adds little further risk and offers big benefits. However, transplant surgery is risky. Each person needs to carefully weigh the potential benefits and risks.
Benefits of Pancreas Transplants
• You may be able to maintain a normal blood glucose level without taking insulin.
• Many of the diabetes-related side effects are prevented or delayed.
• Most people with nerve damage who receive a pancreas transplant do not get worse and sometimes show improvement.
Downsides to Pancreas Transplants
• The body treats the new pancreas as foreign and the immune system attacks the transplanted pancreas.
• Transplant patients must take powerful immunosuppressant drugs to prevent rejection of the new pancreas. Drugs that suppress the immune system can lower resistance to other diseases, such as cancer, and to bacterial and viral infections.
Islet Transplants
Researchers are testing transplanting only the islet cells of the pancreas. These are the cells in the pancreas that secrete insulin. The islets also sense glucose levels in the blood and dispense the right amount of insulin to the blood.
Islets from a deceased person are taken out, purified, and then transferred to a person with type 1 diabetes. These cells then go on to make insulin.
The procedure has been beneficial for some people—allowing them to take less or sometimes no insulin. However, islet transplantation is still considered experimental.
Organ Donors
One of the biggest problems with both pancreas and islet cell transplantation is the shortage of organ donors. About 7,000 bodies are donated for organ transplants each year in the United States—too few to supply islet cells for everyone with type 1 diabetes.
CHAPTER 4
Type 2 Diabetes
Most people (about 95%) with diabetes have type 2 diabetes. Type 2 diabetes tends to develop in people over 40 and used to be called adult-onset diabetes. If you’re reading this chapter, you or someone you love has probably been diagnosed with type 2 diabetes.
However, in recent years, more children and teens are developing type 2 diabetes. Much of this has to do with kids becoming obese and inactive.
Early Symptoms and Tests
Usually, type 2 diabetes does not appear suddenly. Instead, you may have no noticeable symptoms or only mild symptoms for years before diabetes is detected, perhaps during a routine exam or blood test.
Common Symptoms of Type 2 Diabetes
• Frequent urination due to the body trying to flush out excess glucose
• Increased thirst due to dehydration
• Fatigue because the necessary glucose is not getting to your cells
• Blurred vision due to a buildup of fluid in your eyes or elevated glucose levels
• More frequent or slower-healing infections
Tests for Type 2 Diabetes
If your doctor suspects diabetes, he or she will perform a blood test, such as the A1C, fasting plasma glucose test, or the random plasma glucose test, as discussed in chapter 2. If your A1C is 6.5% or higher, your fasting plasma glucose test is 126 mg/dl or higher, or your random plasma glucose test is 200 mg/dl or higher, you will be diagnosed with diabetes. Usually, a second test will be done to confirm the diagnosis.
Causes and Risk Factors
Initially,