Harvard Health Publications and Krames Consults
Type 1 Diabetes Consult
From Harvard Health Publications, brought to you by Krames
Of Interest
With type 1 diabetes, managing your condition requires daily care. To maintain your health or that of a loved one with diabetes, plan ahead. Have extra supplies on hand so that you’re prepared in the event of an emergency. A small makeup or travel bag makes an ideal kit. Think about storing at least three days’ worth of insulin, insulin-delivery supplies, and glucose-monitoring supplies, as well as a source of quick-acting glucose.
In This Booklet You Will Learn
- What type 1 diabetes is and how it affects the body.
- Which medications are used to treat type 1 diabetes.
- Steps you can take to reduce your risk of health problems resulting from type 1 diabetes.
What Is Type 1 Diabetes?
Diabetes is a disease that raises the sugar level in your blood, a condition known as hyperglycemia (high-per-gly-SEE-mee-a), which means high blood sugar. The reason that the sugar level is high in type 1 diabetes is that the body’s immune system destroys cells in the pancreas that produce the hormone insulin. Insulin is needed to transfer sugar from your blood to your body’s cells, which use the sugar to create energy. Because of the lack of insulin, sugar cannot get into cells, causing blood sugar level to rise. When cells are deprived of sugar, they starve. Eventually, this can damage various systems in your body.
Possible Risk Factors
Scientists don’t know what causes the body’s immune system to destroy insulin-making cells in the pancreas. But research so far suggests the following factors may be involved:
- Genes. Type 1 diabetes runs in families. Also, people with type 1 diabetes and their immediate family members (even those who do not have diabetes) are more likely to develop other immune disorders, such as thyroid inflammation, Addison’s disease (failure of the adrenal gland), and lupus.
- Viruses. Some scientists believe that certain viruses may activate type 1diabetes. These may include the Coxsackie virus and those that cause mumps and German measles.
- Foods. Some studies show that eating wheat-containing products and drinking cow’s milk early in life might lead to type 1 diabetes in people who have genes that make them vulnerable. But this research is preliminary. It is too early to tell whether children with a family history of type 1 diabetes should avoid these products.
How the Body Normally Uses Glucose
To gain energy, the body creates fuel from food. During digestion, food is broken down, resulting in a type of sugar called glucose. After leaving the digestive system, glucose enters the bloodstream. This causes the body’s blood glucose (also called blood sugar) level to rise.
As glucose enters the bloodstream, the pancreas is signaled to release insulin. Together, insulin and glucose move throughout the body. For glucose to provide energy to cells, it needs to get inside the cells. That’s where insulin comes in. Insulin opens the cell in a way that allows glucose to enter. Once inside the cell, glucose is used as energy to fuel the cell’s functions.
How Type 1 Diabetes Affects Glucose
With type 1 diabetes, the pancreas becomes less able to make insulin. The digestive process still produces glucose, but without insulin, glucose cannot enter the cells. Instead, the glucose builds up in the bloodstream. As insulin production drops, blood sugar level increases.
Cells that are not being fueled by glucose burn fat instead. While this does supply the cell with energy, it also creates a by-product called ketones. These acids remain in the blood and urine. A buildup of ketones can cause a condition known as ketoacidosis (key-toe-ass-id-DOE-sis), which can be life-threatening.
Type 1 Diabetes Symptoms
Symptoms of type 1 diabetes usually develop quickly, over days or weeks. They can include:
- Extreme thirst
- Frequent urination
- Unintended weight loss
- Fatigue
- Irritability
- Blurry vision
- Tingling or numbness in the hands and feet (in advanced cases)
- Urinary or vaginal yeast infections
The reason you are always thirsty and urinate frequently is because the excess sugar in your blood causes you to pass too much water in your urine. This makes you dehydrated. Unintended weight loss occurs because of dehydration and because the sugar in your urine is carrying away calories.
Inadequate insulin and the high blood sugar level that results also can lead to ketoacidosis. This serious condition occurs because the low level of insulin causes fat to release fatty acids into the blood, which turn into ketones. A high concentration of ketones can cause a coma.
Your Diagnosis
If you have any symptoms of diabetes, see your doctor promptly. Your doctor will take a medical history, and he or she probably will perform one of three simple blood tests:
- A random plasma glucose test. This measures the glucose (sugar) levels in your blood. If your level is above 200 mg/dL (milligrams per deciliter), you probably have diabetes, especially if you also have symptoms.
- A fasting plasma glucose test. This is the standard diagnostic test for diabetes. It requires fasting for at least 8 hours before the test, so that food you’ve eaten won’t make the result inaccurate. A result of 126 mg/dL or above indicates diabetes. If this is your result, get tested again to make sure.
- An oral glucose tolerance test. This test is not often ordered because it is time-consuming and cumbersome. First, your blood sugar is tested after you fast overnight. Next, you drink a sugary solution and your blood is tested again 2 hours later. If the second test shows a glucose level of 200 mg/dL or higher, you have diabetes.
Type 1 Diabetes Treatment
Insulin is the primary treatment for type 1 diabetes. It cannot be taken by mouth because enzymes in the stomach will destroy it. Right now, the standard way to take it is by injection, usually several times a day. The goal is to achieve a lower, stable level of insulin in your blood between meals, and a higher level with meals, to offset the rise in blood sugar that occurs after eating.
Types of Insulin
There are several types of insulin. They can be injected individually, or mixed, after your doctor or nurse shows you how.
- Very-rapid-acting insulins work within 15 minutes of injection, although their effects don’t last as long as other insulins. They are taken just before meals so that you have lots of insulin in your system when the blood sugar from meals starts to rise.
- Rapid-acting types start to lower blood sugar level within 30 to 60 minutes. Their effects peak in 1 to 2 hours but last for 5 to 8 hours.
- Intermediate-acting insulins take about 2 hours to begin working. Their effects peak in anywhere from 4 to 15 hours, and last as long as 18 to 24 hours. They help keep your blood sugar levels steady throughout the day and night.
- Long-acting types have a slow onset and a small peak effect. They can last for as long as 36 hours.
Insulin Delivery
Many people are nervous about injecting themselves, but the equipment available today makes injections virtually painless for most people.
Inhaled insulin is a recent and dramatic change in treating diabetes. Prescribed along with injections, inhaled insulin can reduce the number of injections needed daily.
Monitoring Glucose
If you have type 1 diabetes, it’s vital to keep your blood sugar level within normal range. Doctors call this “tight glycemic control.” The first step in blood sugar control is learning to monitor the level of glucose in your blood. For this reason, glucose meters are standard equipment for many people with diabetes.
Daily Monitoring
Blood sugar level varies throughout the day, and you may not always realize when your sugar dips too low or spikes too high. Close monitoring can help you adjust the timing and amount of insulin doses, which must be balanced with food intake and exercise.
To use a glucose meter, you draw a drop of blood, dip the test strip into the blood, and insert the strip into the meter. Within seconds, the meter gives you your glucose reading. Recording your glucose readings in a log helps you see patterns, such as how activity, stress, and certain foods affect your blood sugar.
Long-term Monitoring
The A1C test (glycosylated hemoglobin test) is a blood test that your doctor performs about every 3 months. Other glucose-monitoring tests provide a snapshot of your blood sugar level at a given moment. The A1C test shows how well you have been managing your blood sugar level over recent weeks. The higher your A1C reading, the higher your average blood sugar level has been during preceding weeks.
Not a Steady State
Ironically, the more you try to strictly control your blood sugar level, the more likely you are to experience hypoglycemia (low blood sugar), so it is important that you and the people around you understand and spot its early warning signs. In addition to watching that your blood sugar level does not dip too low, you also must be careful it does not get too high.
Hypoglycemia
Low blood sugar, or hypoglycemia (high-poe-gly-SEE-mee-a), can be life-threatening. Blood sugar may fall abnormally low from too much insulin, too much exercise for the amount of insulin you are taking (exercise drives down blood sugar level), or from a delayed meal. Symptoms of hypoglycemia include:
- Nervousness, trembling
- Hunger
- Weakness
- Lightheadedness or dizziness
- Confusion, slurred speech
- Sweating, feeling clammy
- Rapid heartbeat
- Irritability
- Drowsiness
- Double vision
- In severe cases, loss of consciousness, seizures, coma
Hyperglycemia
High blood sugar, or hyperglycemia (high-per-gly-SEE-mee-a), is also dangerous. Severe, untreated hyperglycemia can eventually lead to severe dehydration, confusion, loss of consciousness, and coma. Symptoms of hyperglycemia are those of diabetes itself: extreme thirst, frequent urination, weight loss, fatigue, irritability, and blurry vision.
If you are experiencing hypoglycemia, don’t put off treatment. If you can’t check your blood sugar when symptoms begin, treat and check later. Eat or drink 10 to 15 grams of carbohydrates. This amount can be found in:
- 4 to 6 ounces fruit juice
- 2 tablespoons raisins
- 8 ounces low-fat milk
- LifeSavers or jelly beans (about 6)
- Fast-acting glucose tablets
If you are experiencing hyperglycemia, check your blood sugar level and check for ketones. Drink sugar-free, caffeine-free liquids. Take extra insulin as directed, and call your healthcare provider if your blood sugar and ketones do not return to normal range.
Diabetes and Arteries
Having type 1 diabetes puts you at increased risk of atherosclerosis, often called hardening of the arteries. An uncontrolled blood sugar level helps set the stage for artery disease. That’s because high blood sugar can damage arteries by affecting proteins in the artery walls. Over time, the lining of the walls becomes rough, allowing cholesterol and the fatty materials to collect and form plaque. This causes the artery to become stiffer, less elastic. As plaque builds up, blood flow is reduced.
Diabetes Affects All Your Arteries
Artery damage can affect blood flow to the heart and brain, as well as to the legs and feet.
Any artery in your body can narrow with plaque. Also, blood clots and pieces of plaque sometimes break off and travel through the bloodstream until they lodge in a narrowed artery. Organs and tissues beyond that location no longer receive the fresh blood they need to function normally.
Damage to arteries can also affect eyes, feet, kidneys, nerves, teeth, and gums. Good blood sugar control can help prevent or delay such health complications.
Preventing Problems
Research suggests that the “tighter” your blood sugar control, the more likely you are to delay or prevent the serious and sometimes life-threatening complications of the disease. Major complications and steps you can take to delay these health problems are discussed below.
Artery Disease
Diabetes increases the risk of atherosclerosis. The parts of the body that don’t get enough blood can become damaged. Atherosclerosis can affect the heart, brain, eyes, kidneys, feet, and legs. Prevention is the best medicine. This includes controlling blood sugar levels, eating right, getting regular exercise, and quitting smoking. Your doctor may prescribe medications to improve blood pressure, cholesterol levels, or both.
Nerve Damage
Diabetes can cause neuropathy (newr-AH-path-ee). This condition affects the way nerve cells carry messages within the body. Peripheral neuropathy affects the nerves that extend from the spine to the arms and legs. Focal neuropathy damages nerves of the eyes, face, arm, and leg. Autonomic neuropathy causes abnormalities in digestion and sweating. It can also affect blood pressure upon standing, and can cause erectile dysfunction in men. Better blood sugar control lessens certain symptoms. Your doctor also may prescribe medications to combat symptoms.
Damage to Feet
When peripheral neuropathy and poor circulation combine, damage can occur in the feet. Any sore can become severely infected because not enough infection-fighting white blood cells can reach the site. Toes are most vulnerable. The key is to be very aware of your feet. Examine them daily and take special care of them:
- Wash your feet with warm water and soap every day and dry them carefully. Never soak your feet. This can dry and crack skin.
- Massage your feet with a moisturizing cream to prevent cracking.
- Keep toenails well cared for to avoid ingrown nails.
- Put on clean socks each day and wear shoes that fit well.
- Avoid going barefoot.
- See a podiatrist to treat calluses, corns, warts, and other common foot ailments.
- Treat any foot injury immediately.
Eye Disease
Diabetes causes diabetic retinopathy (ret-in-AH-path-ee). This condition damages the blood supply to the retina, the light-sensing structure at the back of the eye. The retina tries to repair itself by developing new blood vessels, but these new vessels grow abnormally, often leaking blood that blocks the passage of light. Eventually, scar tissue can cause the retina to detach, causing permanent vision loss if it is not repaired. To reduce the risk of diabetic retinopathy, visit an ophthalmologist every year for a thorough checkup. If you show signs of retinopathy, your doctor can treat it using a laser to remove excess blood vessels. This may require multiple treatments.
Chronic Kidney Disease
Also called nephropathy (nef-RAH-path-ee), chronic kidney disease is progressive and can lead to kidney failure. When the kidneys can no longer filter enough waste from the blood, mechanical cleansing of the blood (dialysis) or kidney transplant is needed. Diabetes is the leading cause of kidney failure, although most people with diabetes do not develop the condition. Progression of kidney disease can be slowed or prevented by controlling blood sugar and blood pressure levels. Your doctor may prescribe medications that lower blood pressure and protect against kidney damage. Losing weight and reducing salt intake also can help.
Exercise and Glucose Level
Besides improving your heart health and general well-being, exercise can lower your blood sugar level. This is because your hardworking muscles are using the supply of glucose in your bloodstream. The combination of exercise and sugar-lowering medicines can cause blood sugar level to go too low, so people with diabetes should carefully monitor their blood sugar level during and after exercise.
Diet and Glucose Level
Time meals and snacks to keep your blood sugar level from fluctuating too much. Also, follow your healthcare provider’s instructions about monitoring blood sugar and taking insulin before meals.
A dietitian can help you create a personalized meal plan, and help you make healthy dietary choices a permanent part of the way you live.
Choose mostly complex carbohydrates such as vegetables, whole-grain breads and cereals, and simple sugars that exist naturally in fruit and low-fat milk. A diet low in saturated fats, cholesterol, and sweets can help you live a healthier life.
Limit fat. Most of the fat you eat should be monounsaturated and polyunsaturated fat from vegetable sources.
Follow-Up
People with type 1 diabetes should have regular appointments with their doctor and other healthcare professionals, even if their blood sugar level is controlled. With proper treatment, you can control type 1 diabetes. Work with your healthcare provider to get the help you need. Treatment takes time, but it will pay off. It will help you feel better and regain control of your life.
When to Call Your Healthcare Provider
It is particularly important to contact your doctor if you:
- Think you may be experiencing either high or low blood sugar (see page 9).
- Have sudden vision changes.
- Have blood pressure that is consistently over 135/85.
- See hot spots or sores on your legs or feet.
- Have symptoms of nerve damage, including numbness, tingling, or reduced sensitivity to touch.
- Have symptoms of heart disease, such as chest pain, trouble breathing, or extreme fatigue without reason.
Staying On Track
Managing type 1 diabetes requires time, dedication, and new skills. But the positive habits you’re forming will benefit your health and your life. So stick with your diabetes treatment plan. Test your blood sugar and take your medications as directed. Visit your healthcare provider to ensure that your treatment is working. And continue to spend time with the people who support the healthy changes you’re making. These relationships can do a lot to keep you on track.
Common Concerns
Managing type 1 diabetes starts with you. It’s your choices, your lifestyle—your life. What can you do to make dealing with diabetes a priority in your life? You can work toward tight blood sugar control. Proper use of insulin is vital for this. But for best results, you should also try to eat healthier and be active each day. The list below offers ways to help you get started. Check off the tips you’ll try this week. You might even want to add a few ideas of your own.
What You Can Do
For Proper Insulin Use
- Keep extra insulin, syringes, pens, or pump supplies on hand.
- Test glucose daily as directed, including before and after meals.
- Keep a backup supply of insulin in the refrigerator.
- Keep a diabetes supply kit nearby at all times.
To Eat Healthier
- Try to eat meals and snacks at the same time each day.
- Learn which foods contain the most carbohydrates, and which types of carbohydrates affect your blood sugar most.
- Eat more whole grains, fresh fruits and vegetables, low-fat dairy products, and lean meats and fish.
- Avoid liquid sugars in sodas, sports drinks, and fruit drinks.
To Be More Active
- Aim for a total of 30 minutes of planned activity daily.
- Take three 10-minute walks a day.
- Ride a bike, take a swim, hike with friends.
- Wash the car, rake the yard, run the vacuum.
- Park farther away and walk more when running errands.
Further Reading
For additional information about diabetes, visit our website: www.health.harvard.edu
More information is available from:
- American Diabetes Association: www.diabetes.org
- National Institute of Diabetes and Digestive and Kidney Diseases: www.niddk.nih.gov
- National Diabetes Information Clearinghouse: www.diabetes.niddk.nih.gov