title: Anxiety, depression and timing of insulin treatment among people with type 2 diabetes: Nine-year follow-up of the Nord-Trøndelag Health Study, Norway.
abstract: BACKGROUND
  Depression and anxiety have been found to be predictors of poor health outcomes in diabetes, but mechanisms are still unclear.
  
  
  OBJECTIVE
  To examine whether symptoms of anxiety and depression were associated with timing of initiating insulin therapy.
  
  
  METHODS
  A cohort study of insulin-naive particpants with type 2 dabetes completed the Hospital Anxiey and Depression Scale, HADS-A (n = 731) and/or the HADS-D (n = 768) in the communy-based Nord-Trøndelag Health Study (1995-1997). Information on insulin initiation was retrieved from the Norwegian Prescription Database from January 1, 2004 to November 21, 2012. Cox regression analyses were used to estimate the association between symptoms of anxiety, depression and time to insulin initiation.
  
  
  RESULTS
  At baseline, 19% reported anxiety symptoms (score≥8) and 18% depressive symptoms (score≥8). After a mean follow-up of 4.4 (SD 3.6) years, 337 (40%) participants had started insulin therapy. After adjustment for sociodemographic and clinical variables, anxiety symptoms were associated with later initiation of insulin therapy (HR 0.70, 95% CI 0.49-0.99), while depressive symptoms were not. Considering groups simultaneously, having both elevated depressive and elevated anxiety symptoms was associated with later time to insulin initiation (HR 0.62, 95% CI 0.39-0.99), while having only anxiety symptoms (without depressive) HR 0.81, 95% CI 0.50-1.32) or only depressive symptoms (without anxiety) (HR 1.08, 95% CI 0.68-1.72) were not.
  
  
  CONCLUSIONS
  Anxiety was associated with a later initiation of insulin, while depressive symptoms were not. Persons with both elevated levels of anxiety and depression were also less likely to start insulin therapy. These results need further testing in other prospective studies.
authors.affiliation: Centre for Evidence-Based Practice, Bergen University College, Norway; Department of Endocrinology, Stavanger University Hospital, Norway. Electronic address: marjolein.iversen@hib.no.
authors.forename: M M
authors.initials: MM
authors.lastname: Iversen
authors.affiliation: Center of Research on Psychology in Somatic Diseases (CoRPS), Department of Medical and Clinical Psychology, Tilburg University, The Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Nefs
authors.affiliation: Department of Global Public Health and Primary Care, University of Bergen, Norway.
authors.forename: G S
authors.initials: GS
authors.lastname: Tell
authors.affiliation: Centre for Evidence-Based Practice, Bergen University College, Norway.
authors.forename: B
authors.initials: B
authors.lastname: Espehaug
authors.affiliation: Department of Community Medicine and General Practice, HUNT Research Centre, Norwegian University of Science and Technology, Norway.
authors.forename: K
authors.initials: K
authors.lastname: Midthjell
authors.affiliation: Centre for Evidence-Based Practice, Bergen University College, Norway.
authors.forename: M
authors.initials: M
authors.lastname: Graue
authors.affiliation: Center of Research on Psychology in Somatic Diseases (CoRPS), Department of Medical and Clinical Psychology, Tilburg University, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Pouwer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001007:Anxiety / Q000209:etiology*; D015331:Cohort Studies; D003863:Depression / Q000175:diagnosis / Q000209:etiology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000188:drug therapy; D005260:Female; D006801:Humans; D007328:Insulin / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009664:Norway; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D007328:Insulin
keywords: Anxiety; Depression; Insulin therapy; Insulin-naive people; Prospective study; Type 2 diabetes