CF-Related Diabetes Risk Factors
Cystic fibrosis-related diabetes (CFRD) is one of the most common non-respiratory complications of cystic fibrosis (CF). It differs from Type 1 and 2 Diabetes, yet shares similar features of each.1
What causes CFRD?
Normally, the pancreas produces insulin which helps control and stabilize blood glucose levels. In CF, sticky, thick mucus causes scarring of the pancreas, decreasing its ability to produce insulin. Consequently, insulin deficiency causes an increase in blood sugar levels, resulting in various symptoms.1
Risk factors for CFRD development
Unlike type 2 diabetes, lifestyle factors are not typically associated with the development of CFRD.2
Risk factors for CFRD include:2-4
- Liver disease – CFRD is more common in people who have CF-related liver disease. Thick fluids build up, blocking the small ducts of the liver. Eventually, this can lead to scarring of the liver, also known as fibrosis and cirrhosis.
- Increased age – the risk of CFRD increases as people age: 45-50% of people over the age of 30 with CF have CFRD. In comparison, it affects 19% of adolescents between the ages of 11-17, and 40% of people aged 18-29 years.
- Female gender – after 30 years of age, the prevalence of CFRD is higher in women than men.
- Severe CF genotypes – CFRD is more common in people with severe CF genotypes, such as F508del mutation.
- Lung function – the condition is more common in people with greater declines in lung function and more frequent pulmonary exacerbations.
- Impaired nutrition status – poor nutrition status increases the risk of developing glucose imbalances.
- Sleep in adolescents – poor sleep correlates with higher blood glucose levels and lower insulin sensitivity.
How does CFRD impact CF?
CFRD and CF have a close relationship, with the severity of one impacting the other. CF can lead to CFRD, and in turn, CFRD can worsen CF outcomes. For example, CFRD can have detrimental effects on nutritional status and lung function. The further impairment in nutritional status occurs because insulin has a vital role in maintaining lean body mass.1-3
Role of CFTR modulators in CFRD
The role of CFTR modulators, such as ivacaftor, in preventing CFRD is unclear at this time. Some early studies have demonstrated some improvements in insulin secretion after four months of ivacaftor therapy.5 To determine whether the new agents have a significant impact on reducing the incidence of CFRD, more trials need to be conducted.
If you have been recently diagnosed with CFRD, it is important not to blame yourself. Managing diabetes alone is challenging; managing diabetes in addition to CF is even more challenging. CFRD can be managed with glucose monitoring and insulin; however, it can be burdensome.1 Fortunately, awareness of CFRD has been increasing, making it easier to connect with others who are successfully managing the two conditions simultaneously. With the right emotional, peer, and clinical support, both conditions can be managed effectively.
Do you have the risk factors for developing CFRD? Do you have CFRD now? Share your experience in the comments below.
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