title: The impact of policy guidelines on hospital antibiotic use over a decade: a segmented time series analysis.
abstract: BACKGROUND
  Antibiotic pressure contributes to rising antibiotic resistance. Policy guidelines encourage rational prescribing behavior, but effectiveness in containing antibiotic use needs further assessment. This study therefore assessed the patterns of antibiotic use over a decade and analyzed the impact of different modes of guideline development and dissemination on inpatient antibiotic use.
  
  
  METHODS
  Antibiotic use was calculated monthly as defined daily doses (DDD) per 100 bed days for nine antibiotic groups and overall. This time series compared trends in antibiotic use in five adjacent time periods identified as 'Segments,' divided based on differing modes of guideline development and implementation: Segment 1--Baseline prior to antibiotic guidelines development; Segment 2--During preparation of guidelines and booklet dissemination; Segment 3--Dormant period with no guidelines dissemination; Segment 4--Booklet dissemination of revised guidelines; Segment 5--Booklet dissemination of revised guidelines with intranet access. Regression analysis adapted for segmented time series and adjusted for seasonality assessed changes in antibiotic use trend.
  
  
  RESULTS
  Overall antibiotic use increased at a monthly rate of 0.95 (SE = 0.18), 0.21 (SE = 0.08) and 0.31 (SE = 0.06) for Segments 1, 2 and 3, stabilized in Segment 4 (0.05; SE = 0.10) and declined in Segment 5 (-0.37; SE = 0.11). Segments 1, 2 and 4 exhibited seasonal fluctuations. Pairwise segmented regression adjusted for seasonality revealed a significant drop in monthly antibiotic use of 0.401 (SE = 0.089; p<0.001) for Segment 5 compared to Segment 4. Most antibiotic groups showed similar trends to overall use.
  
  
  CONCLUSIONS
  Use of overall and specific antibiotic groups showed varied patterns and seasonal fluctuations. Containment of rising overall antibiotic use was possible during periods of active guideline dissemination. Wider access through intranet facilitated significant decline in use. Stakeholders and policy makers are urged to develop guidelines, ensure active dissemination and enable accessibility through computer networks to contain antibiotic use and decrease antibiotic pressure.
authors.affiliation: Global Health, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden; Department of Pharmacology & Clinical Pharmacology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Sujith J
authors.initials: SJ
authors.lastname: Chandy
authors.affiliation: Department of Pharmacology & Clinical Pharmacology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Girish S
authors.initials: GS
authors.lastname: Naik
authors.affiliation: Department of Pharmacy, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Reni
authors.initials: R
authors.lastname: Charles
authors.affiliation: Department of Biostatistics, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Visalakshi
authors.initials: V
authors.lastname: Jeyaseelan
authors.affiliation: Department of Civil and Environmental Engineering, Tufts University School of Engineering, Medford, Massachusetts, United States of America; Department of Gastrointestinal Sciences, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Elena N
authors.initials: EN
authors.lastname: Naumova
authors.affiliation: Department of Medicine, Christian Medical College, Vellore, Vellore, Tamil Nadu, India.
authors.forename: Kurien
authors.initials: K
authors.lastname: Thomas
authors.affiliation: Global Health, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Cecilia Stalsby
authors.initials: CS
authors.lastname: Lundborg
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D006291:Health Policy; D006761:Hospitals; D006801:Humans; D017410:Practice Guidelines as Topic; D010818:Practice Patterns, Physicians'; D012621:Seasons; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents