20 years of the Montreal Cystic Fibrosis Related Diabetes Screening Cohort: key insights

The Montreal Cystic Fibrosis Related Diabetes Screening Cohort (MCFC) was established in 2004 to study the prevalence, risk factors and management of cystic fibrosis-related diabetes, a significant extrapulmonary complication of cystic fibrosis with an increasing prevalence due to improved cystic fibrosis survival rates. The aims of this review are to highlight the key insights gained from monitoring the MCFC over 20 years, and to discuss the challenges and advantages of establishing such a cohort in a rare disease like cystic fibrosis.

Adult people with cystic fibrosis were recruited from 2004 onward in Montreal, Canada, excluding those already diagnosed with cystic fibrosis-related diabetes. Clinical and biological results (including oral glucose tolerance tests) were recorded regularly.

Findings from the MCFC contributed to a better understanding of cystic fibrosis-related diabetes pathophysiology (in particular, the joint roles of reduced insulin secretion and added insulin resistance) and its relationship with lung function. Over the years, we observed a shift towards overweight and obesity among cystic fibrosis patients, along with improved lung function. This could be due to improved cystic fibrosis care and to the introduction of cystic fibrosis transmembrane conductance regulator modulators. We were also able to validate new, simplified screening modalities and management strategies (e.g. physical activity) for cystic fibrosis-related diabetes.

The MCFC has contributed to the understanding of cystic fibrosis-related diabetes and informed best practice guidelines. Future research will focus on how cystic fibrosis transmembrane conductance regulator modulators influence glycaemic control and cardiometabolic health in people with cystic fibrosis.