title: Predicting the Individual Risk of Acute Severe Colitis at Diagnosis.
abstract: OBJECTIVE
  Acute severe colitis [ASC] is associated with major morbidity. We aimed to develop and externally validate an index that predicted ASC within 3 years of diagnosis.
  
  
  METHODS
  The development cohort included patients aged 16-89 years, diagnosed with ulcerative colitis [UC] in Oxford and followed for 3 years. Primary outcome was hospitalization for ASC, excluding patients admitted within 1 month of diagnosis. Multivariable logistic regression examined the adjusted association of seven risk factors with ASC. Backwards elimination produced a parsimonious model that was simplified to create an easy-to-use index. External validation occurred in separate cohorts from Cambridge, UK, and Uppsala, Sweden.
  
  
  RESULTS
  The development cohort [Oxford] included 34/111 patients who developed ASC within a median 14 months [range 1-29]. The final model applied the sum of 1 point each for extensive disease, C-reactive protein [CRP] > 10mg/l, or haemoglobin < 12g/dl F or < 14g/dl M at diagnosis, to give a score from 0/3 to 3/3. This predicted a 70% risk of developing ASC within 3 years [score 3/3]. Validation cohorts included different proportions with ASC [Cambridge = 25/96; Uppsala = 18/298]. Of those scoring 3/3 at diagnosis, 18/18 [Cambridge] and 12/13 [Uppsala] subsequently developed ASC. Discriminant ability [c-index, where 1.0 = perfect discrimination] was 0.81 [Oxford], 0.95 [Cambridge], 0.97 [Uppsala]. Internal validation using bootstrapping showed good calibration, with similar predicted risk across all cohorts. A nomogram predicted individual risk.
  
  
  CONCLUSIONS
  An index applied at diagnosis reliably predicts the risk of ASC within 3 years in different populations. Patients with a score 3/3 at diagnosis may merit early immunomodulator therapy.
authors.affiliation: Translational Gastroenterology Unit, Oxford University Hospitals, Oxford, UK.|Dipartimento di Medicina Interna e Specialità Mediche, 'Sapienza', University of Rome, Rome, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Cesarini
authors.affiliation: Centre for Statistics in Medicine, University of Oxford, Oxford, UK.
authors.forename: Gary S
authors.initials: GS
authors.lastname: Collins
authors.affiliation: Department of Medical Sciences, Gastroenterology, Uppsala University, Uppsala, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Rönnblom
authors.affiliation: Gastroenterology Unit, Cambridge University Hospitals, Cambridge, UK.|Gastroenterology Unit, Hospital Amato Lusitano, Castelo Branco, Portugal.
authors.forename: Antonieta
authors.initials: A
authors.lastname: Santos
authors.affiliation: Department of Cellular Pathology, Oxford University Hospitals, Oxford, UK.
authors.forename: Lai Mun
authors.initials: LM
authors.lastname: Wang
authors.affiliation: Department of Medical Sciences, Gastroenterology, Uppsala University, Uppsala, Sweden.
authors.forename: Daniel
authors.initials: D
authors.lastname: Sjöberg
authors.affiliation: Gastroenterology Unit, Cambridge University Hospitals, Cambridge, UK.
authors.forename: Miles
authors.initials: M
authors.lastname: Parkes
authors.affiliation: Translational Gastroenterology Unit, Oxford University Hospitals, Oxford, UK.
authors.forename: Satish
authors.initials: S
authors.lastname: Keshav
authors.affiliation: Translational Gastroenterology Unit, Oxford University Hospitals, Oxford, UK.
authors.forename: Simon P L
authors.initials: SP
authors.lastname: Travis
mesh_terms: D000208:Acute Disease; D000328:Adult; D000367:Age Factors; D002097:C-Reactive Protein / Q000378:metabolism; D003093:Colitis, Ulcerative / Q000097:blood / Q000175:diagnosis* / Q000473:pathology*; D003113:Colonoscopy; D018450:Disease Progression; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D049451:Nomograms; D011237:Predictive Value of Tests; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors
chemical_list: D006454:Hemoglobins; D002097:C-Reactive Protein
keywords: Biomarkers; acute severe colitis; clinical trials; prediction; ulcerative colitis