MyCyFAPP PERT model

This study is part of a large HORIZON 2020 project Innovative approach to self-management and social welfare of Cystic Fibrosis patients in Europe: development, validation and implementation of a telematics tool)

In the paediatric age, secondary malnutrition to Cystic Fibrosis (CF) has a negative impact in the patients clinical evolution for its repercussion, among others, on the digestive and absorptive functions and the appetite. Maintaining an
adequate nutritional status is an indispensable aspect of the CF treatment, since it directly affects the quality of life, the lung function and the survival. Pancreatic insufficient patients require supplementation with exogenous pancreatic enzyme therapy (PERT), with the aim to reduce the fecal losses of fat, protein and biliary acids and the deficit of fatsoluble
vitamins associated to this disease. It is crucial that the administration of pancreatic extracts is in the correct dose and, moreover, adapted to each moment and each meal.

The main objective in the first approach is to obtain a mathematical predictive model
(MPM) adapted to each patients' gastrointestinal conditions that calculates the optimal amount of enzymatic supplements for the optimal fat digestion of any food or meal. So for each patient an individual correction factor (ICF)
will be obtained. Afterwards, in a second step, the objective is to validate the MPM by assessing how much the final fat in stools after applying the ICF deviates from the optimal value (<6g of fat/24h).

The MPM would be eventually implemented into a mobile APP, and together with an enzyme requirements database for different food products and meals digestion, will be able to, through a calculation algorithm, predict the amount of PERD required for a specific meal, and taking into account individual needs for correction of the dose. This will allow for
self-management of this essential therapy regardless of time and place.

The study consists of 3 parts of each 2 x 1 day.
Part 1:

- Follow a test diet with a fixed PERT dose (theoretical dose).

- Collection of feces that is marked by intake of color capsules.

- Keeping a nutritional diary.

Part 2:

- same as part 1 except the use of a PERT dosage that takes the individual correction factor (as obtained by part 1)
into account.

Part 3:

- same as part 2, so with a personal PERT dosage, but follow of a free diet

The 3 parts will take place during a period of 9 months.

The interventions consist of following a test diet, the use of PERT (own capsules, test dose), the collection of feces that is marked by the intake of color capsules and keeping a nutritional diary. These interventions take place during 3 x 2 weekends.