title: Long-term cost-effectiveness of collaborative care (vs usual care) for people with depression and comorbid diabetes or cardiovascular disease: a Markov model informed by the COINCIDE randomised controlled trial.
abstract: To evaluate the long-term cost-effectiveness of collaborative care (vs usual care) for treating depression in patients with diabetes and/or coronary heart disease (CHD).
  
  
  
  36 primary care general practices in North West England.
  
  
  
  387 participants completed baseline assessment (collaborative care: 191; usual care: 196) and full or partial 4-month follow-up data were captured for 350 (collaborative care: 170; usual care: 180). 62% of participants were male, 14% were non-white. Participants were aged ≥18 years, listed on a Quality and Outcomes Framework register for CHD and/or type 1 or 2 diabetes mellitus, with persistent depressive symptoms. Patients with psychosis or type I/II bipolar disorder, actively suicidal, in receipt of services for substance misuse, or already in receipt of psychological therapy for depression were excluded.
  
  
  
  Collaborative care consisted of evidence-based low-intensity psychological treatments, delivered over 3 months and case management by a practice nurse and a Psychological Well Being Practitioner.
  
  
  
  As planned, the primary measure of cost-effectiveness was the incremental cost-effectiveness ratio (cost per quality-adjusted life year (QALY)). A Markov model was constructed to extrapolate the trial results from short-term to long-term (24 months).
  
  
  
  The mean cost per participant of collaborative care was £317 (95% CI 284 to 350). Over 24 months, it was estimated that collaborative care was associated with greater healthcare usage costs (net cost £674 (95% CI -30 953 to 38 853)) and QALYs (net QALY gain 0.04 (95% CI -0.46 to 0.54)) than usual care, resulting in a cost per QALY gained of £16 123, and a likelihood of being cost-effective of 0.54 (willingness to pay threshold of £20 000).
  
  
  
  Collaborative care is a potentially cost-effective long-term treatment for depression in patients with comorbid physical and mental illness. The estimated cost per QALY gained was below the threshold recommended by English decision-makers. Further, long-term primary research is needed to address uncertainty associated with estimates of cost-effectiveness.
  
  
  
  ISRCTN80309252; Post-results.
authors.affiliation: Manchester Centre for Health Economics, University of Manchester, Manchester, UK.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Camacho
authors.affiliation: Manchester Centre for Health Economics, University of Manchester, Manchester, UK.
authors.forename: Dionysios
authors.initials: D
authors.lastname: Ntais
authors.affiliation: Mental Health and Addiction Research Group, University of York, York, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Coventry
authors.affiliation: Centre for Primary Care, University of Manchester, Manchester, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Bower
authors.affiliation: The School of Nursing, Midwifery and Social Work, University of Manchester, Manchester, UK.
authors.forename: Karina
authors.initials: K
authors.lastname: Lovell
authors.affiliation: Primary Care & Health Sciences, University of Keele, Staffordshire, UK.|Centre for Primary Care, University of Manchester, Manchester, UK.
authors.forename: Carolyn
authors.initials: C
authors.lastname: Chew-Graham
authors.affiliation: NHS Health Education North West, Manchester, UK.
authors.forename: Clare
authors.initials: C
authors.lastname: Baguley
authors.affiliation: Centre for Primary Care, University of Manchester, Manchester, UK.
authors.forename: Linda
authors.initials: L
authors.lastname: Gask
authors.affiliation: Mental Health Research Group, University of Exeter, Exeter, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Dickens
authors.affiliation: Manchester Centre for Health Economics, University of Manchester, Manchester, UK.
authors.forename: Linda M
authors.initials: LM
authors.lastname: Davies
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000150:complications / Q000191:economics / Q000628:therapy*; D015897:Comorbidity; D003299:Cooperative Behavior; D003362:Cost-Benefit Analysis; D003863:Depression / Q000150:complications / Q000191:economics / Q000628:therapy*; D003866:Depressive Disorder / Q000150:complications / Q000191:economics / Q000628:therapy*; D003920:Diabetes Mellitus / Q000191:economics / Q000628:therapy*; D004739:England; D058006:General Practice; D017048:Health Care Costs; D006801:Humans; D008390:Markov Chains; D008875:Middle Aged; D010348:Patient Care Team; D011320:Primary Health Care; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D059039:Standard of Care; D016896:Treatment Outcome; D055815:Young Adult
keywords: HEALTH ECONOMICS; MENTAL HEALTH; PRIMARY CARE