title: Prevalence of personality disorder in alcohol and drug services and associated comorbidity.
abstract: OBJECTIVE
  To compare the prevalence of personality disorder in alcohol and drug populations with special attention to its impact on psychopathology and service characteristics.
  
  
  METHODS
  Cross-sectional survey.
  
  
  METHODS
  Three alcohol and four drug services in four urban UK centres.
  
  
  METHODS
  Two hundred and sixteen drug and 64 alcohol service patients randomly sampled from current treatment populations.
  
  
  METHODS
  A treatment population census recorded demographic and diagnostic data. Patient interviews assessed the presence, cluster type and severity of personality disorder using the Quick Personality Assessment Schedule (PAS-Q). Other psychopathology was measured using the Comprehensive Psychopathological Rating Scale (CPRS). A case-note audit recorded psychotic psychopathology using the OPCRIT schedule and data regarding social morbidity.
  
  
  RESULTS
  The overall prevalence of personality disorder was 37% in the drug service sample and 53% in the alcohol service sample. The distribution of severity and clusters differed markedly between the two samples. There was a significant association between the severity of personality disorder and psychopathology in both samples. Levels of morbidity associated with clusters B and C were similar. Clinical diagnosis of personality disorder showed high specificity but low sensitivity when compared to PAS-Q.
  
  
  CONCLUSIONS
  In both alcohol and drug service populations, personality disorder is associated with significantly increased rates of psychopathology and social morbidity that worsens with increasing severity of the disorder. Despite this, personality disorder is poorly identified by clinical staff. The PAS-Q may be useful as a clinical assessment tool in the substance misuse population for the early identification and management of patients with personality disorder.
authors.affiliation: Central and North-west London Mental Health NHS Trust, UK. owen.bowdenjones@nhs.net
authors.forename: Owen
authors.initials: O
authors.lastname: Bowden-Jones
authors.forename: Muhammad Z
authors.initials: MZ
authors.lastname: Iqbal
authors.forename: Peter
authors.initials: P
authors.lastname: Tyrer
authors.forename: Nicholas
authors.initials: N
authors.lastname: Seivewright
authors.forename: Sylvia
authors.initials: S
authors.lastname: Cooper
authors.forename: Ali
authors.initials: A
authors.lastname: Judd
authors.forename: Tim
authors.initials: T
authors.lastname: Weaver
mesh_terms: D015897:Comorbidity; D003430:Cross-Sectional Studies; D003625:Data Collection; D006801:Humans; D010349:Patient Compliance; D010554:Personality Disorders / Q000453:epidemiology* / Q000209:etiology; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D019966:Substance-Related Disorders / Q000150:complications / Q000453:epidemiology*; D006113:United Kingdom / Q000453:epidemiology