title: Group-Based Trajectory Modeling of Healthcare Financial Charges in Inflammatory Bowel Disease: A Comprehensive Phenotype.
abstract: OBJECTIVE
  Inflammatory bowel disease (IBD) is a heterogeneous group of chronic inflammatory gastrointestinal conditions with variable disease courses often requiring significant healthcare expenditures. We aimed to identify disease trajectory patterns based on longitudinal financial expenditures and to assess the association of classic disease activity parameters with financial charges.
  
  
  METHODS
  This was an analysis of a consented, prospective, natural history IBD registry (2009-2013) from a tertiary IBD center of 2,203 patients and their associated medical charges excluding pharmacy expenses. We applied group-based trajectory modeling to longitudinal healthcare financial charges to determine patterns of charges. We assessed the association between charge patterns and disease activity, quality of life, healthcare utilization, and medication requirement.
  
  
  RESULTS
  The final model included 1,600 IBD patients with 5-year charges. We identified six distinct trajectories over the study period. Consistently High charges were associated with Crohn's disease (66.0% Consistently High patients, P<0.01), perianal involvement (22.6%, P<0.01), ulcerative colitis extent (89.7% extensive, P=0.01), prior IBD surgery (52.5%, P<0.01), and depression/anxiety (36.2%, P<0.01). Compared with other trajectories, Consistently High charges had higher 5-year disease activity indices (Harvey-Bradshaw P<0.01; ulcerative colitis activity index P<0.01), elevated C-reactive protein rates (72.3%, P<0.01), IBD surgery (64.5%, P<0.01), hospitalization (97.2%, P<0.01), corticosteroid (70.9%, P<0.01) and antitumor necrosis factor requirement (50.4%, P<0.01), and worse quality of life (P<0.01). Annual trends in parameters were reflected in temporal changes in financial charges. The majority of financial burden stemmed from inpatient care.
  
  
  CONCLUSIONS
  Healthcare financial charges represent a novel phenotype in IBD that reflect trends in classic disease activity parameters and allow for subgroup identification of temporal disease trajectories.
authors.affiliation: Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.|Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Jianfei
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Click
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Alyce M
authors.initials: AM
authors.lastname: Anderson
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Ioannis E
authors.initials: IE
authors.lastname: Koutroubakis
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Claudia Ramos
authors.initials: CR
authors.lastname: Rivers
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Jana G
authors.initials: JG
authors.lastname: Hashash
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Dunn
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Marc
authors.initials: M
authors.lastname: Schwartz
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Swoger
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Arthur
authors.initials: A
authors.lastname: Barrie
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Miguel
authors.initials: M
authors.lastname: Regueiro
authors.affiliation: Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.|Division of General Internal Medicine, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Chung-Chou H
authors.initials: CC
authors.lastname: Chang
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh School of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: David G
authors.initials: DG
authors.lastname: Binion