Cohort profile of the PRoteomic Evaluation and Discovery in an IBD Cohort of Tri-service Subjects (PREDICTS) study: Rationale, organization, design, and baseline characteristics

Abstract

Purpose: The etiology of Inflammatory Bowel Disease (IBD) remains currently unknown but evidence would suggest that it results from a complex interplay between genetic susceptibility genes, the intestinal microbiome and the environment, resulting in an increased response towards microbial and self-antigens, followed by the development of pre-clinical intestinal inflammation as a precursor to overt clinical disease. Efforts are needed to provide insights into the characterization of the disease, the possible prediction of complications, and the detection of a pre-clinical disease state where, through early screening and intervention, disease course can be reversed, attenuated or even prevented. A consortium of academic, industry and governmental organization investigators initiated this study to enable an assessment of pre-disease biomarkers in patients newly diagnosed with Crohn's disease (CD) and ulcerative colitis (UC).

Participants: A retrospective cohort of 1000 UC and 1000 CD cases with 500 matched controls was drawn from an active duty US military personnel population with relevant inclusion criteria with three associated pre-disease and a single disease-associated archived serum samples.

Findings to date: The PREDICTS study has been established as a biorepository platform study to perform novel discovery and analysis efforts in the field of IBD and proteomic systems biology.

Future plans: This study is poised to enable the assessment of novel biomarkers within the serum compartment to be analyzed with the goal of identifying pre-disease signals that ultimately predict disease risk, and further elucidate disease pathogenesis in the early stages of the disease process, and identify novel exposures that increase disease risk.

Fig. 1

Serum Sample Selection concurrent with and prior to IBD diagnosis for PREDICTS subjects. Legend: Sample A was the first sample available following the initial medical encounter in which an IBD diagnosis was made. In the absence of this sample, the last sample prior to that medical encounter was selected. Samples B and C represent the serum samples stored from the three preceding biennial (e.g. every two years) HIV screening test. Sample D represented the earliest serum sample available in the repository.

Fig. 2

Predicts study Governance structure.

Fig. 3

Year of incident diagnosis (or matching).

Fig. 4

Box and whisker plots of serum sample timing stratified by CD, UC and healthy controls. Legend. UC, ulcerative colitis; CD, Crohn's disease, HC, healthy controls. The box and whisker plots represent the median (mid-line) 25% and 75% quartiles (boxes) and the 1st and 3rd quartiles + 1.5 * the interquartile range (whiskers).