Research Reveals More About Unique Cystic Fibrosis Diabetes

People who live with cystic fibrosis are at extremely high risk for developing diabetes, but not the kind that most people are diagnosed with. Cystic fibrosis-related diabetes (CFRD) is a unique type of diabetes that is common to individuals with cystic fibrosis.

As a patient gets older, the likelihood that they will become diabetic increases. Consequently, mortality and morbidity also increase, meaning that the secondary diagnosis has a large impact on the overall progression of cystic fibrosis.

The most prevalent forms of diabetes in ordinary patients are type 1 and type 2 diabetes. The most common is type 2 diabetes, which most often occurs in overweight or obese adults who either become unable to produce enough insulin, or who fail to have a proper insulin response. Type 1 diabetes is an autoimmune disorder, where the immune system attacks the pancreas and limits or destroys available insulin to the body. Insulin is key in maintaining good health, as it breaks down and absorbs energy from nutrients.

CFRD tends to present with a mixture of symptoms from type 1 and type 2 diabetes. In the case of CFRD patients, the problem is not an autoimmune problem, but the individual will be insulin deficient like a type 1 diabetes patient would be. They are like type 2 diabetes patients in that they are unable to produce enough insulin to maintain health, but unlike type 2 diabetes patients, insulin injections will not always work right away to remedy blood sugar problems.

The Cystic Fibrosis Foundation cites scarring of the pancreas as the root of the problem, and as the cause of CFRD. They believe that the scarring limits the pancreas’s ability to produce insulin, which explains why CFRD patients present with the unique form of diabetes. Recently, a professor at Kyoto Prefectural University of Medicine in Japan took a closer look at the relationship between insulin production and cystic fibrosis, and his findings suggest that the cause and effects of CFRD may be more complicated than originally thought.

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Yoshinori Marunaka is a Professor at Kyoto Prefectural University of Medicine, where he serves as Chairman of the Department of Molecular Cell Physiology at the Graduate School of Medical Science. He recently led a review of studies that had previously examined the relationships between the gene that causes cystic fibrosis and insulin. The mutated cystic fibrosis gene causes defects in the cystic fibrosis transmembrane conductance regulator (CFTR) protein, which Marukana suspected had a significant role in the development of cystic fibrosis-related diabetes.

Researchers had long been able to verify that the defective CFTR protein had a role to play in the production of insulin, but they were unsure as to what exactly that role was. Damage to the pancreas is common in almost all cystic fibrosis patients, but there seemed to be no way of determining exactly how the defective CFTR protein was responsible, if at all. Cystic fibrosis affects so many areas of the body that researchers were content to chalk it all up to fibrotic scarring, which allowed them to treat it.

Read on to learn more about this discovery and what it means for the future of cystic fibrosis care.