title: Covert dose reduction is a distinct type of medication non-adherence observed across all care settings in inflammatory bowel disease.
abstract: BACKGROUND
  Non-adherence by dose omission is common and deleterious to outcomes in Inflammatory Bowel Disease (IBD), but covert dose reduction (CDR) remains unexplored.
  
  
  OBJECTIVE
  To determine frequency and attitudinal predictors of overall medication non-adherence and of covert dose reduction as separate entities.
  
  
  METHODS
  A cross sectional questionnaire was undertaken involving IBD patients in three different geographical regions and care settings. Demographics, medication adherence by dose omission, and rate of patient initiated dose reduction of conventional meds without practitioner knowledge (CDR) were assessed, along with attitudes toward IBD medication.
  
  
  RESULTS
  Of 473 respondents (mean age 50.3 years, 60.2% female) frequency of non-adherence was 21.9%, and CDR 26.9% (p<0.001). By logistic regression, significant independent predictors of non-adherence were dissatisfaction with the patient-doctor relationship (p<0.001), depression (p=0.001), anxiety (p=0.047), and negative views regarding medication efficacy (p<0.001) or safety (p=0.017). Independent predictors of covert dose reduction included regular complementary medicine (CAM) use (p<0.001), experiencing more informative (p<0.001) and comfortable (p=0.006) consultations with alternative practitioners, disbelieving doctor delivered information (p=0.021) and safety concerns regarding conventional medication (p<0.001). Neither the frequency of non-adherence (p=0.569) nor CDR (p=0.914) differed between cohorts by different treatment settings.
  
  
  CONCLUSIONS
  Covert dose reduction of IBD medication is more common than omission of medication doses, predicted by different factors to usual non-adherence, and has not been previously reported in IBD. The strongest predictor of CDR is regular CAM use.
authors.affiliation: Department of Gastroenterology and Hepatology, Flinders Medical Centre, South Australia, Australia; Flinders University of South Australia, Australia. Electronic address: ramonreme@adam.com.au.
authors.forename: Réme
authors.initials: R
authors.lastname: Mountifield
authors.affiliation: IBD Service, Dept. Gastroenterology and Hepatology & School of Medicine, University of Adelaide at Royal Adelaide Hospital, South Australia, Australia; Flinders University of South Australia, Australia. Electronic address: jane.andrews@health.sa.gov.au.
authors.forename: Jane M
authors.initials: JM
authors.lastname: Andrews
authors.affiliation: School of Nursing and Midwifery, University of South Australia, Australia. Electronic address: antonina-mikocka-walus@unisa.com.au.
authors.forename: Antonina
authors.initials: A
authors.lastname: Mikocka-Walus
authors.affiliation: Department of Gastroenterology and Hepatology, Flinders Medical Centre, South Australia, Australia; Flinders University of South Australia, Australia. Electronic address: peter.bampton@flinders.edu.au.
authors.forename: Peter
authors.initials: P
authors.lastname: Bampton
mesh_terms: D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D001007:Anxiety / Q000523:psychology; D001294:Attitude to Health; D001315:Australia / Q000453:epidemiology; D000529:Complementary Therapies / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D003863:Depression / Q000523:psychology; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy*; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D010817:Physician-Patient Relations; D011795:Surveys and Questionnaires
chemical_list: D000893:Anti-Inflammatory Agents; D005938:Glucocorticoids; D007166:Immunosuppressive Agents
keywords: Complementary and Alternative Medicine; Dose modification;; Inflammatory Bowel Disease; Medication adherence; Medication attitudes