title: Patterns and predictors of re-admission to hospital with self-poisoning in Scotland.
abstract: OBJECTIVE
  To identify factors influencing hospital re-admission with self-poisoning.
  
  
  METHODS
  Retrospective cohort follow-up study using national linked hospital discharge data.
  
  
  METHODS
  All Scottish adult hospital episodes with self-poisoning admissions were captured using NHS Scotland Information Services Division data, and first-time 'index' admissions between 1996 and 2002 were identified. Re-admission rate was defined as the proportion of index admissions who went on to have one or more further self-poisoning admissions within 2 years. The effects of various potential risk factors for re-admission were examined using logistic regression.
  
  
  RESULTS
  In total, 50,891 index admissions were identified; of these, 8278 patients were re-admitted. The 1-year re-admission rate was 12.2%. Older patients (>65 years) were least likely to be re-admitted [odds ratio (OR) 0.40, P<0.01, compared with patients aged 15-24 years]. No differences were found between males and females. Previous psychiatric hospital admission was associated with an increased re-admission rate (OR 2.85, P<0.01), with a diagnosis of personality disorder associated with the highest rate of re-admission (OR 4.59, P<0.01). Other factors predicting re-admission were: increased deprivation (quintile 3: OR 1.16, P<0.01; quintile 5: OR 1.15, P<0.01, compared with quintile 1); taking medicines for chronic disease, drug dependency (OR 1.6 and 1.19, P < or = 0.02) or antidepressants (OR 1.11, P=0.01) (compared with paracetamol); and co-ingestion of three or more agents (OR 1.37, P<0.01).
  
  
  CONCLUSIONS
  Younger age, higher deprivation, ingestion of certain drug groups or multiple drug types, and prior psychiatric hospital admission are all risk factors for re-admission with self-poisoning. Personality disorder carried the greatest risk of re-admission. These findings may provide a basis to develop policies to reduce re-admission rates in the future.
authors.affiliation: Queen's Medical Research Institute, Clinical Pharmacology Unit, University of Edinburgh, 47 Little France Crescent, Edinburgh EH164TJ, UK.
authors.forename: R A
authors.initials: RA
authors.lastname: Payne
authors.forename: J J
authors.initials: JJ
authors.lastname: Oliver
authors.forename: M
authors.initials: M
authors.lastname: Bain
authors.forename: A
authors.initials: A
authors.lastname: Elders
authors.forename: D N
authors.initials: DN
authors.lastname: Bateman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission / Q000706:statistics & numerical data*; D011041:Poisoning / Q000453:epidemiology* / Q000523:psychology*; D012189:Retrospective Studies; D012307:Risk Factors; D012606:Scotland / Q000453:epidemiology; D013406:Suicide, Attempted / Q000706:statistics & numerical data*