A common complication people with cystic fibrosis (CF) may experience is diabetes — also known as cystic fibrosis-related diabetes (CFRD), a unique type of diabetes. Around 40%–50% of adults with CF develop diabetes.1 CFRD has shares characteristics of both type 1 and type 2 diabetes.2

The sticky and thick mucus common in CF damages the pancreas, leading to insufficient insulin production, much like in type 1 diabetes. The pancreas continues to produce insulin, but not enough to stay healthy. Likewise, people with CF don’t have a normal response to insulin (the hallmark of type 2 diabetes), a condition known as being “insulin resistant,” and one especially evident during an illness or when using steroid medications. In fact, insulin resistance has a major impact on those taking corticosteroids to treat CF symptoms.1

Most CFRD patients don’t know they are diabetic until the disease is diagnosed. For this reason, CF care guidelines for CFRD recommend that people with CF, ages 10 and older, undergo an oral glucose tolerance test every year.

CFRD symptoms include increased thirst and urination, excessive fatigue, weight loss, and an unexplained decline in lung function. But unlike people with type 1 and 2 diabetes, those with CFRD need to keep to a high-calorie diet to maintain a healthy body weight.

How is CFRD treated?

CFRD treatment includes keeping blood sugar normal levels (usually with insulin), monitoring blood-sugar level levels, maintaining an active lifestyle (150 minutes of moderate aerobic exercise per week is recommended), and eating healthy foods.

There are different types of insulin, classified by how long they last in the body and how fast they work. Insulin improves nutrient absorption in order to maintain healthy body weight and nutritional status.2

Oral hypoglycemics, or anti-diabetic drugs, may be used if difficulties exist in taking insulin.1

Exercise is important to maintaining good lung function and improving the body’s response to insulin. Again, people with CFRD are advised to do at least 150 minutes of moderate aerobic exercise (like jogging, walking quickly, or playing sports) each week and to regularly have their blood glucose levels tested to manage CFRD.2


Cystic Fibrosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.


  1. http://www.diabetes.co.uk/cystic-fibrosis.html
  2. https://www.cff.org/Living-with-CF/Cystic-Fibrosis-related-Diabetes/