A grumbling concern: an international survey of gastrointestinal symptoms in cystic fibrosis in the modulator era

Background

Gastrointestinal symptoms in cystic fibrosis (CF) are common and intrusive to daily life. Relieving gastrointestinal symptoms was identified as an important research priority and previously explored in an international survey in 2018. However, following the widespread introduction of cystic fibrosis transmembrane conductance regulator (CFTR) modulators in 2019, the landscape of CF treatment has changed. We repeated an online survey to further describe gastrointestinal symptoms and their effect on quality of life (QoL) in the CFTR modulator era.

Methods

An electronic survey consisting of closed questions and free text responses was distributed via social media and professional networks for a period of one month between March - April 2022. People with CF (pwCF), their family and friends, and healthcare professionals (HCPs) were invited to take part.

Results

There were 164 respondents: 88 pwCF (54%), 22 (13%) family, and 54 (33%) healthcare professionals (HCPs). A total of 89/110 (81%) pwCF or family members reported CFTR modulator treatment. The most commonly reported symptoms were wind / gas, rumbling stomach noises, loose motions (modulator) and bloating (no modulator). Abdominal pain and bloating had the greatest impact on QoL.

For those on a CFTR modulator, the proportion of pwCF reporting “no change” or “worse” for all of the symptoms surveyed was greater than the proportion reporting an improvement. Following modulator introduction, dietary changes were recommended by 28/35 (80%) of HCPs and reported by 38/76 (50%) lay respondents. Changes in medication were recommended by 19/35 (54%) HCPs and reported by 44/76 (58%) of patients and family members.

Conclusion

This survey has shown that gastrointestinal symptoms remain prevalent in pwCF in the CFTR modulator era, though the nature of these symptoms may have changed. A better understanding of the underlying pathophysiology of these symptoms is essential. Future clinical studies should focus on improving symptoms and QoL.

Plain language summary

What is already known: Gastrointestinal symptoms are common and intrusive to everyday life for people with cystic fibrosis (CF), however the majority of studies reporting gastrointestinal symptoms in CF are published prior to the widespread introduction of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies. These are medications which target the underlying defect in CF rather than the consequences of CFTR failure.

What this study adds: Through this survey, we describe the similarities and differences of gastrointestinal symptoms for people with CF on modulator therapy compared to those not receiving modulators. Comparisons were also made to our previous work which was completed in 2018 prior to the licencing of the newest, and most widely used modulator, Elexacaftor / Tezacaftor / Ivacaftor (ETI).

How this study might affect future research: This survey provides a snapshot into gastrointestinal symptoms for people with CF which will be of benefit for researchers as well as clinicians caring for people with CF. These results will inform the development of a CF-specific gastrointestinal patient reported outcome measure for people with CF that can be used in clinical trials.