Type 1 Diabetes
Introduction
Type 1 diabetes has no cure, but the outlook for people who have the disease is far better today than it was even 20 years ago. Living with type 1 diabetes can still be a challenge, but improvements in patient education, blood sugar monitoring and insulin delivery have simplified the daily routine of managing the disease. Thanks to these and other advances, people with type 1 diabetes may now have life expectancies comparable to those of people without diabetes. The risk of disabling complications from type 1 diabetes has also been reduced.
Signs and symptoms
The signs and symptoms of type 1 diabetes often appear after a flu-like illness and gradually intensify over the course of a few weeks. Typical features may include:
- Increased thirst and frequent urination. With type 1 diabetes, excess sugar (glucose) builds up in your bloodstream. A high level of blood glucose pulls water from your body's tissues, making you thirsty. As a result, you drink more fluids and urinate more. The excess sugar in your bloodstream passes through your kidneys and leaves your body in your urine.
- Extreme hunger. The basic defect in type 1 diabetes— an inability to produce insulin, the hormone necessary for glucose to enter cells and fuel their functions — leaves your muscles and organs energy depleted. That triggers intense hunger. Eating fills your stomach, but the hunger persists because, without insulin, the glucose produced from dietary carbohydrates never reaches your body's energy-starved tissues.
- Weight loss. Despite eating a lot to relieve their constant hunger, people with type 1 diabetes lose weight, sometimes rapidly. That's because the body's cells are deprived of glucose and energy as glucose is lost into the urine. Without the energy glucose supplies, cells die at an increased rate before they can divide and replace themselves. Muscle tissues and fat stores shrink, and body weight declines.
- Blurred vision. A high level of blood glucose pulls fluid from all your tissues, including the lenses of your eyes. The decrease in fluid affects your ability to focus.
- Fatigue. When your cells are deprived of glucose, you become tired and irritable.
Causes
In type 1 diabetes, the body has little or no insulin because the immune system — which normally fights harmful bacteria or viruses — has attacked and destroyed the insulin-producing cells in the pancreas, a gland located just behind the stomach. Similar immune system attacks on different body tissues occur in a number of other diseases, which are known as autoimmune diseases. Such diseases include multiple sclerosis, in which the immune system attacks the substance that coats nerve fibers, and rheumatoid arthritis, in which the immune system attacks the linings of the joints.
Researchers believe that factors such as genetics, diet and exposure to certain viruses all may be involved in triggering different autoimmune diseases, including type 1 diabetes. Because type 1 diabetes typically appears in the wake of an infection, the immune attack on insulin-producing cells may be a consequence of the immune system's reaction to the earlier infection.
Lack of insulin results in diabetes because of the vital role insulin plays in making glucose — the body's fuel — available to cells. During digestion, your body transforms the carbohydrates from such foods as bread, fruits and milk products into different types of sugar molecules. One of these sugar molecules is glucose, the main energy source for your body. Glucose is absorbed directly into your bloodstream after you eat, but it can't enter your cells without the help of insulin.
Normally, your pancreas produces insulin continuously, raising its output in response to the increase in blood sugar that occurs after you eat. This extra insulin "unlocks" your cells so that more sugar can enter, providing your body with energy as well as maintaining a normal level of sugar in your blood.
Your liver also plays a key role in maintaining a normal blood sugar level. If you have more glucose than your cells need for energy, your body can remove the excess glucose from your bloodstream and store it in your liver as glycogen — a form of stored glucose. Then, when you run low on glucose — if you haven't eaten for a while, say — your body can tap into the stored glucose and release it into your bloodstream.
When your pancreas functions normally, your blood glucose fluctuates in response to exercise, stress, infections, food and a variety of other factors. But your hormonal system — including but not limited to the insulin-producing pancreas — continuously makes complex adjustments that keep your blood sugar levels within set limits.
Treatment
Treatment is a life-long commitment in type 1 diabetes. The ongoing goal is to keep your blood sugar levels as close to normal as possible. By controlling your blood sugar, you can avoid short-term complications and delay or prevent long-term complications. In fact, research shows that tight control of blood sugar levels can reduce the risk of diabetes-related heart attacks and strokes by more than 50 percent.
You'll work closely with your diabetes care team — doctor, nurse, dietitian and diabetes educator — to balance your insulin intake with your diabetes meal plan and activity level.
Blood sugar monitoring
If you've just received a diagnosis of type 1 diabetes, monitoring your blood sugar may seem like an overwhelming task. But once you learn to measure your blood sugar and understand how important it is, you'll feel more comfortable with the procedure and better able to manage your disease. You'll test your blood sugar at least twice a day. Depending on what type of insulin therapy you select or require — single dose injections, multiple dose injections or insulin pump — you may establish a pattern of testing four times each day, or even more often.
Testing is crucial because it tells you whether you're keeping glucose levels within your target range. Your doctor sets this target range based on your age, the presence of diabetes-related complications or other medical conditions, and your ability to recognize signs and symptoms of hypoglycemia soon enough to eat something sugary before you have serious symptoms. The ideal target range before meals is 90 to 130 mg/dL. Two hours after a meal, your blood sugar should be below 180 mg/dL.
When you have type 1 diabetes, the timing of your insulin injections and the type of insulin used have dramatic effects on your blood sugar. But even if you take insulin and eat on a very rigid schedule, the amount of sugar in your blood can change unpredictably. Self-monitoring — testing your blood sugar and keeping a record of the results — helps you understand the factors that affect your blood sugar, so you can learn to make adjustments in your treatment. You'll learn from experience how your blood sugar changes in response to:
- Food. Food raises your blood sugar level. Blood sugar is highest one to two hours after a meal. What and how much you eat, and the time of day, also affect your blood sugar level.
- Exercise and physical activity. In general, the more active you are, the lower your blood sugar. Physical activity moves sugar from your bloodstream into your cells. Aerobic exercises such as brisk walking, jogging or biking are especially good for reducing blood sugar. Because aerobic exercise is so effective at lowering blood sugar, your health care team will help you figure out how to adjust your insulin dose before you exercise so that your levels don't fall too low.
- Medications. You take insulin to lower your blood sugar. In fact, insulin is the basis for all the other aspects of type 1 diabetes treatment. But medications you take for other conditions may affect your blood glucose levels as well, sometimes making it necessary to alter your diabetes treatment plan. Among the drugs most likely to increase blood glucose are corticosteroids, used to treat asthma and many other types of inflammation, and thiazides, which are often the first line of treatment for high blood pressure.
- Illness. The physical stress of a cold or other illness causes your body to produce hormones that raise your blood sugar level. The additional sugar helps promote healing. But if you have diabetes, more sugar can be a problem. In addition, a fever increases your metabolism, speeding your cells' utilization of insulin. As a result, you may need to take more or larger doses of insulin when you're running a fever. Whatever your symptoms, it's important to monitor your glucose levels frequently when you're sick.
- Alcohol. Even a small amount of alcohol — about 2 ounces — can cause your sugar levels to fall too low. If you choose to drink, do so only in moderation. And monitor your blood sugar before and after consuming alcohol to see how it affects you. Also, keep in mind that alcohol counts as carbohydrate calories in your diet.
- Fluctuations in hormone levels. The female hormone estrogen typically makes cells more responsive to insulin, and progesterone makes cells more resistant. Although these two hormones fluctuate throughout the menstrual cycle, the majority of women don't notice a corresponding change in blood sugar levels. Those who do are more likely to experience changes in blood sugar during the third week of their menstrual cycle, when estrogen and progesterone levels are highest.
Informations obtained from National Institute of Health.