An investigation of the dietary management of dysglycaemia in cystic fibrosis

Abstract

Background
Dysglycaemia is an increasingly common complication of cystic fibrosis (CF). It ultimately results in the development of CF-related diabetes, which is associated with increased mortality and morbidity. Low glycaemic index (GI) diets are recommended for non-CF diabetes and GI dietary intervention could help manage dysglycaemia in CF populations, but evidence is lacking.

Aim
To increase knowledge related to the dietary management of dysglycaemia in CF and to explore the feasibility of GI dietary intervention for people with CF and glucose abnormalities.

Methods
Three studies were conducted. The first study was a systematic review of dietary interventions for managing dysglycaemia in CF. The second study assessed the feasibility of implementing a GI dietary intervention, developed by the researcher, in a sample of 24 individuals with CF and dysglycaemia. Baseline and follow-up assessments completed after 12-weeks of dietary intervention included measures of glycaemia, dietary intake, and clinical status. The third study was a qualitative acceptability assessment of the intervention and feasibility study processes. Semi-structured interviews were held with study participants and some of their parents (n=7). In addition, three focus groups were held with 23 CF healthcare professionals (HCPs) to gain their perspectives on the intervention and the broader management of dysglycaemia in CF.

Results
The review identified a lack of robust evidence to support dietary interventions for managing dysglycaemia in CF. The feasibility study and acceptability assessment indicated that the proposed GI dietary intervention and study processes were feasible and acceptable to people with CF and dysglycaemia and to HCPs. The feasibility study also provided preliminary evidence that the intervention may have a favourable effect on reducing dietary GI.

Conclusion
This thesis presents preliminary data that indicates GI dietary intervention is feasible and acceptable for dysglycaemia management in CF. Further research is needed to confirm its effectiveness and clinical utility.

Date of Award	6 Dec 2022
Original language	English
Awarding Institution	University of Bristol
Supervisor	Julian P Hamilton-Shield (Supervisor), Fiona E Lithander (Supervisor), Katrina M Turner (Supervisor) & Simon C Langton Hewer (Supervisor)