Learning About Cystic Fibrosis-Related Diabetes

Cystic fibrosis-related diabetes (CFRD) is a type of diabetes that can occur in some people who have cystic fibrosis (CF).

CF causes mucus in the body to become thick and sticky. This mucus builds up and causes problems in many of the body’s organs, especially the lungs and pancreas.

When mucus builds up in your pancreas, it causes healthy tissue to scar. This can make it hard for you to absorb nutrients from food. And you may develop diabetes.

When you have CFRD, the pancreas does not make enough of the hormone insulin. Insulin helps your body turn food into energy and control blood sugar levels.

If you have CFRD and get sick, take steroid medicine, or are pregnant, your body may not respond to insulin in the right way. This is called insulin resistance. When this happens, it can cause your insulin levels to go up or down.

CFRD can also make the effects that CF has on your lungs worse and affect how long you may live. But when CFRD is diagnosed early and treated, you can live a full and active life.

You may not have any symptoms. Or your symptoms may be like the CF symptoms you already have.

When you have CFRD, you may:

• Feel very thirsty.
• Need to urinate often.
• Lose weight without trying. Or you may not be able to gain weight.
• Feel more tired than usual.
• Have changes in your breathing.
• Get more infections.

Doctors recommend that people with CF ages 10 and older be tested every year for CFRD.

Getting diagnosed and treated early can improve long-term health.

To diagnose CFRD, your doctor will do an oral glucose tolerance test (OGTT). This measures the body's ability to use a type of sugar called glucose. That is the body's main source of energy.

You take the test in the morning after not eating or drinking for 8 hours. At the start of the test, your doctor will take a sample of your blood to check your glucose level. Then you drink a “glucose drink" that has a lot of sugar. After drinking the liquid, your blood sugar levels will be measured at set times.

Doctors treat CFRD by helping you keep your blood sugar in a target range.

Taking insulin, being active, and eating healthy foods can help you manage your blood sugar. And checking your blood sugar can help you make sure you stay in your target range.

Your CF and diabetes care teams can give you information to help you stay active and eat healthy foods.

Insulin helps your body take in energy, or calories, from the food you eat and turn it into the energy your body needs.

You can give yourself shots of insulin or get it with an insulin pump attached to your body. Your diabetes care team, including certified diabetes educators, will teach you how to calculate the amount of insulin you need based on what you eat.

Some people wear a continuous glucose monitor (CGM) and an insulin pump. The devices communicate with each other in what is called a "closed-loop system." This takes some of the burden off you of checking your insulin levels often and calculating how much insulin you need.

Calories in food come from carbohydrates, protein, and fat. Foods with carbohydrates turn into blood sugar. Your care team will work with you to develop a nutrition plan that supports a healthy diet.

Since carbohydrate foods affect your blood sugar the most, your care team may teach you how to count carbohydrates. Some foods affect how slowly or quickly your body processes carbohydrates, so educators may offer tips on how to prevent insulin spikes and dips.

Physical activity is good for your lungs and can improve your body’s reaction to insulin. Check with your doctor first before starting an exercise program. Your doctor can advise you on how to exercise safely.

Examples of exercise include:

• Brisk walking, jogging, and cycling.
• Yoga and gardening.
• Rowing and swimming.
• Weight-lifting and high-intensity interval training.

Your diabetes care team may recommend that you check your blood sugar levels several times a day. Your team will teach you how to do this.

You can do this with a finger prick to test your blood with a test strip before meals and exercise. Or you can wear a continuous glucose monitor (CGM) attached to your body. You can use your smartphone to "talk" to your CGM so you can monitor your glucose levels.

Exercise causes blood sugar levels to drop because it uses sugar for energy. Your team may instruct you to check your blood sugar levels before, during, and after exercise.