title: The impact of comorbid personality difficulties on response to IAPT treatment for depression and anxiety.
abstract: The UK's Improving Access to Psychological Therapies (IAPT) initiative provides evidence-based psychological interventions for mild to moderate common mental health problems in a primary care setting. Predictors of treatment response are unclear. This study examined the impact of personality disorder status on outcome in a large IAPT service. We hypothesised that the presence of probable personality disorder would adversely affect treatment response.
  
  
  METHODS
  We used a prospective cohort design to study a consecutive sample of individuals (n = 1249).
  
  
  RESULTS
  Higher scores on a screening measure for personality disorder were associated with poorer outcome on measures of depression, anxiety and social functioning, and reduced recovery rates at the end of treatment. These associations were not confounded by demographic status, initial symptom severity nor number of treatment sessions. The presence of personality difficulties independently predicted reduced absolute change on all outcome measures.
  
  
  CONCLUSIONS
  The presence of co-morbid personality difficulties adversely affects treatment outcome among individuals attending for treatment in an IAPT service. There is a need to routinely assess for the presence of personality difficulties on all individuals referred to IAPT services. This information will provide important prognostic data and could lead to the provision of more effective, personalised treatment in IAPT.
authors.affiliation: King's College London, Institute of Psychiatry, Psychology and Neuroscience, Department of Clinical Psychology, Addiction Sciences Building, 4 Windsor Walk, London, SE5 8AF, UK. Electronic address: elizabeth.e.goddard@kcl.ac.uk.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Goddard
authors.affiliation: Southwark Psychological Therapies Service, South London and Maudsley NHS Foundation Trust, Eileen Skellern House, Denmark Hill, SE5 8AZ, London, UK. Electronic address: janet.wingrove@slam.nhs.uk.
authors.forename: Janet
authors.initials: J
authors.lastname: Wingrove
authors.affiliation: King's College London, Institute of Psychiatry, Psychology and Neuroscience, Health Services and Population Research Department, De Crespigny Park, London, SE5 8AF, UK. Electronic address: paul.moran@kcl.ac.uk.
authors.forename: Paul
authors.initials: P
authors.lastname: Moran
mesh_terms: D000328:Adult; D001007:Anxiety / Q000523:psychology* / Q000628:therapy*; D003863:Depression / Q000523:psychology* / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010554:Personality Disorders / Q000523:psychology* / Q000628:therapy; D011446:Prospective Studies; D011613:Psychotherapy / Q000379:methods; D016896:Treatment Outcome
keywords: Anxiety; Cognitive behaviour therapy; Depression; IAPT; Personality disorder; Treatment outcome