title: Is Timing of Medical Therapy Related to Outcome in Painful Chronic Pancreatitis?
abstract: OBJECTIVE
  The authors investigated if timing of medical treatment is associated with the analgesic effect of pregabalin or placebo in patients with chronic pancreatitis (CP).
  
  
  METHODS
  Sixty-four patients received pregabalin (150-300 mg twice a day) or matching placebo for 3 consecutive weeks. Responders to treatment were defined as patients with a reduction in clinical pain scores of 30% or greater. Factors associated with timing of pain treatment (ie, duration of CP and opioid usage) were collected at baseline. In addition, other factors that potentially could influence outcome (eg, clinical pain scores prior to study medication, diabetes, and exocrine pancreatic insufficiency) were also included. Conventional groupwise logistic regression and analysis on the individual patient level with a machine learning technique were used to predict treatment response.
  
  
  RESULTS
  In the conventional statistical analysis duration of CP (odds ratio, 0.9; 95% confidence interval, 0.8-1.1; P = 0.3) and opioid treatment (odds ratio, 1.0; 95% confidence interval, 0.9-1.1; P = 0.6) were not associated with pain relief. In addition, none of the supplementary factors were associated with treatment response (all P > 0.1). Likewise, in the individual patient-level analysis, none of the included variables reached classification accuracies greater than chance level (all P > 0.1).
  
  
  CONCLUSIONS
  Pregabalin can be added as adjuvant analgesic at any time point during the disease course of CP.
authors.affiliation: From the *Mech-Sense, Department of Gastroenterology and Hepatology, Aalborg University Hospital, Aalborg, Denmark; †Pain and Nociception Neuroscience Research Group, Department of Surgery, and ‡Department of Anesthesiology, Pain and Palliative Care, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands; §Department of Clinical Medicine and Center for Sensory-Motor Interaction (SMI), Aalborg University, Aalborg, Denmark.
authors.forename: Søren S
authors.initials: SS
authors.lastname: Olesen
authors.forename: Carina
authors.initials: C
authors.lastname: Graversen
authors.forename: Stefan A
authors.initials: SA
authors.lastname: Bouwense
authors.forename: Oliver H G
authors.initials: OH
authors.lastname: Wilder-Smith
authors.forename: Harry
authors.initials: H
authors.lastname: van Goor
authors.forename: Asbjørn M
authors.initials: AM
authors.lastname: Drewes
mesh_terms: D000328:Adult; D000368:Aged; D000700:Analgesics / Q000627:therapeutic use; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy* / Q000209:etiology; D010147:Pain Measurement / Q000379:methods; D050500:Pancreatitis, Chronic / Q000150:complications*; D010919:Placebos; D000069583:Pregabalin / Q000627:therapeutic use*; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000700:Analgesics; D010919:Placebos; D000069583:Pregabalin