title: Overcrowding in hospital wards as a predictor of antidepressant treatment among hospital staff.
abstract: OBJECTIVE
  This report assessed whether hospital ward overcrowding predicts antidepressant use among hospital staff.
  
  
  METHODS
  The extent of hospital ward overcrowding was determined using administrative records of monthly bed occupancy rates between 2000 and 2004 in 203 somatic illness wards in 16 Finnish hospitals providing specialized health care. Information on job contracts for personnel was obtained from the employers' registers. Comprehensive daily data on purchased antidepressant prescriptions (World Health Organization's Anatomical Therapeutic Chemical classification code N06A) for nurses (N=6,699) and physicians (N=641) was derived from national registers. Cox proportional hazards models were used to examine the association between bed occupancy rate and subsequent antidepressant treatment. Monthly bed occupancy rates were used as a time-dependent exposure that could change in value over the course of observation. Hazard ratios were adjusted for sex, age, occupation, type and length of employment contract, hospital district, specialty, and calendar year.
  
  
  RESULTS
  Exposure over 6 months to an average bed occupancy rate over 10% in excess of the recommended limit was associated with new antidepressant treatment. This association followed a dose-response pattern, with increasing bed occupancy associated with an increasing likelihood of antidepressant use. There was no evidence of reverse causality; antidepressant treatment among employees did not predict subsequent excess bed occupancy.
  
  
  CONCLUSIONS
  The increased risk of antidepressant use observed in this study suggests that overcrowding in hospital wards may have an adverse effect on the mental health of staff.
authors.affiliation: Finnish Institute of Occupational Health, Helsinki, Finland. marianna.virtanen@ttl.fi
authors.forename: Marianna
authors.initials: M
authors.lastname: Virtanen
authors.forename: Jaana
authors.initials: J
authors.lastname: Pentti
authors.forename: Jussi
authors.initials: J
authors.lastname: Vahtera
authors.forename: Jane E
authors.initials: JE
authors.lastname: Ferrie
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Stansfeld
authors.forename: Hans
authors.initials: H
authors.lastname: Helenius
authors.forename: Marko
authors.initials: M
authors.lastname: Elovainio
authors.forename: Teija
authors.initials: T
authors.lastname: Honkonen
authors.forename: Kirsi
authors.initials: K
authors.lastname: Terho
authors.forename: Tuula
authors.initials: T
authors.lastname: Oksanen
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimäki
mesh_terms: D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use*; D001509:Bed Occupancy / Q000706:statistics & numerical data*; D015331:Cohort Studies; D003441:Crowding / Q000523:psychology*; D003866:Depressive Disorder / Q000188:drug therapy* / Q000453:epidemiology; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D005260:Female; D005387:Finland; D006306:Health Surveys; D006748:Hospital Departments / Q000706:statistics & numerical data*; D006767:Hospitals, District / Q000706:statistics & numerical data; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008505:Medical Staff, Hospital / Q000523:psychology* / Q000706:statistics & numerical data; D008875:Middle Aged; D009741:Nursing Staff, Hospital / Q000523:psychology* / Q000706:statistics & numerical data; D009784:Occupational Diseases / Q000188:drug therapy* / Q000453:epidemiology; D011446:Prospective Studies; D012307:Risk Factors; D016526:Workload / Q000523:psychology* / Q000706:statistics & numerical data
chemical_list: D000928:Antidepressive Agents