Assessment of Responsiveness to Treatment by Experience Sampling Method
Assessment of Responsiveness to Treatment by Experience Sampling Method
Reliable evaluation of symptoms and their improvement during treatment is crucial in both
 diagnosing and evaluating response to treatment in IBS. Currently used end-of-day evaluations
 are considered sub-optimal and the Experience Sampling Method (ESM) was proposed previously
 as a more accurate symptom assessment method. Aim of this study is to evaluate the
 responsiveness of the developed ESM-PROM in assessing changes in abdominal pain and stool
 frequency after linaclotide treatment of IBS-C patients.
The primary objective of this study is to assess the internal and external responsiveness of
 the ESM-PROM in examining changes in symptom scores between baseline and post-treatment.
 Secondary objectives are to identify differences in characteristics between responders and
 non-responders to linaclotide and to assess for side effects of linaclotide treatment, using
 the ESM-PROM. This is a prospective, observational, single-group, open-label study, initiated
 and performed in Maastricht University Medical Center (MUMC+). The study population will
 conclude 30 IBS-C subjects that are newly prescribed with linaclotide by their treating
 physician at the outpatient department of gastroenterology and hepatology in the Maastricht
 UMC+. Primary study outcomes are the weekly average of the mean and maximum abdominal pain
 scores per day on the ESM-PROM per period (i.e. baseline, after 4 weeks and after 12 weeks).
 The ESM-PROM is completed during 7 consecutive days at each period and therefore, the
 measurements start one week before linaclotide treatment (baseline) and end one week after
 finishing linaclotide treatment (after 12 weeks). Further endpoints are the change scores of
 abdominal pain between pre- and post-treatment, measured using the ESM-PROM. Additionally,
 the proportion of overall responders to linaclotide treatment after 4 and 12 weeks assessed
 using the conventional end-of-day diary will be used to evaluate external responsiveness.
 Further endpoints are symptom scores as reported using the ESM-PROM, concerning abdominal
 pain, bloating, abdominal fullness, fecal urgency, stool consistency, straining, CSBM
 frequency and SBM frequency. Secondary outcomes are other factors measured using the
 ESM-PROM, i.e. non-GI physical symptoms, psychological status at the moment of symptom
 assessment, contextual information regarding the moment of symptom assessment as well as
 information on food and substance intake.
Inclusion Criteria:

 -  Age between 18 and 75 years;

 -  A diagnosis of IBS-C according to Rome IV criteria:

 Recurrent abdominal pain, on average, at least 1 day per week in the last 3 months,
 associated with 2 or more of the following criteria: 1) Relation to defecation; 2)
 Association with a change in stool frequency; 3) Association with a change in stool form
 (appearance). Criteria fulfilled for the last 3 months with symptom onset at least 6 months
 ago. Reported stool consistency over the last 3 months: At least 25% of bowel movements are
 hard and lumpy stools (BSFS 1 or 2) and less than 25% of bowel movements are watery stools
 (BSFS 6 or 7).

 -  Negative colonoscopy in the past 5 years prior to inclusion;

 -  Treatment in primary care unsuccessful for 12 months;

 -  Ability to understand, read and speak the Dutch language;

 -  Ability to understand how to utilize the MEASuRE app on a smartphone.

 Exclusion Criteria:

 -  Appendectomy or cholecystectomy within 2 months or other abdominal surgeries within 6
 months before entry into the study;

 -  A history of laxative abuse;

 -  Current use of drugs that could initiate constipation (e.g. narcotics);

 -  Use of any IBS-related drugs possibly causing constipation (e.g. tricyclic
 antidepressants) are a reason for exclusion, unless usage is on a stable dose for at
 least 30 days before inclusion and there is no plan to change the dose during the
 study period.