title: Antibiotic treatment failure in four common infections in UK primary care 1991-2012: longitudinal analysis.
abstract: OBJECTIVE
  To characterise failure of antibiotic treatment in primary care in the United Kingdom in four common infection classes from 1991 to 2012.
  
  
  METHODS
  Longitudinal analysis of failure rates for first line antibiotic monotherapies associated with diagnoses for upper and lower respiratory tract infections, skin and soft tissue infections, and acute otitis media.
  
  
  METHODS
  Routine primary care data from the UK Clinical Practice Research Datalink (CPRD).
  
  
  METHODS
  Adjusted rates of treatment failure defined by standardised criteria and indexed to year 1 (1991=100).
  
  
  RESULTS
  From 58 million antibiotic prescriptions in CPRD, we analysed 10,967,607 monotherapy episodes for the four indications: 4,236,574 (38.6%) for upper respiratory tract infections; 3,148,947 (28.7%) for lower respiratory tract infections; 2,568,230 (23.4%) for skin and soft tissue infections; and 1,013,856 (9.2%) for acute otitis media. In 1991, the overall failure rate was 13.9% (12.0% for upper respiratory tract infections; 16.9% for lower respiratory tract infections; 12.8% for skin and soft tissue infections; and 13.9% for acute otitis media). By 2012, the overall failure rate was 15.4%, representing an increase of 12% compared with 1991 (adjusted value indexed to first year (1991) 112, 95% confidence interval 112 to 113). The highest rate was seen in lower respiratory tract infections (135, 134 to 136). While failure rates were below 20% for most commonly prescribed antibiotics (amoxicillin, phenoxymethylpenicillin (penicillin-V), and flucloxacillin), notable increases were seen for trimethoprim in the treatment of upper respiratory tract infections (from 29.2% in 1991-95 to 70.1% in 2008-12) and for ciprofloxacin (from 22.3% in 1991-95 to 30.8% in 2008-12) and cefalexin (from 22.0% in 1991-95 to 30.8% in 2008-12) in the treatment of lower respiratory tract infections. Failure rates for broad spectrum penicillins, macrolides, and flucloxacillin remained largely stable.
  
  
  CONCLUSIONS
  From 1991 to 2012, more than one in 10 first line antibiotic monotherapies for the selected infections were associated with treatment failure. Overall failure rates increased by 12% over this period, with most of the increase occurring in more recent years, when antibiotic prescribing in primary care plateaued and then increased.
authors.affiliation: Cochrane Institute of Primary Care and Public Health, Cardiff University, Cardiff, UK Global Epidemiology, Pharmatelligence, Cardiff, UK currie@cardiff.ac.uk.
authors.forename: Craig J
authors.initials: CJ
authors.lastname: Currie
authors.affiliation: Global Epidemiology, Pharmatelligence, Cardiff, UK.
authors.forename: Ellen
authors.initials: E
authors.lastname: Berni
authors.affiliation: Global Epidemiology, Pharmatelligence, Cardiff, UK.
authors.forename: Sara
authors.initials: S
authors.lastname: Jenkins-Jones
authors.affiliation: Cochrane Institute of Primary Care and Public Health, Cardiff University, Cardiff, UK.
authors.forename: Chris D
authors.initials: CD
authors.lastname: Poole
authors.affiliation: Established Pharmaceuticals, Abbott Healthcare Products, Weesp, Netherlands.
authors.forename: Mario
authors.initials: M
authors.lastname: Ouwens
authors.affiliation: Established Pharmaceuticals, Abbott Healthcare Products, Weesp, Netherlands.
authors.forename: Stefan
authors.initials: S
authors.lastname: Driessen
authors.affiliation: Established Pharmaceuticals, Abbott Healthcare Products, Weesp, Netherlands.
authors.forename: Hanka
authors.initials: H
authors.lastname: de Voogd
authors.affiliation: Cochrane Institute of Primary Care and Public Health, Cardiff University, Cardiff, UK Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Butler
authors.affiliation: Global Epidemiology, Pharmatelligence, Cardiff, UK.
authors.forename: Christopher Ll
authors.initials: CL
authors.lastname: Morgan
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001424:Bacterial Infections / Q000188:drug therapy* / Q000191:economics*; D006801:Humans; D008137:Longitudinal Studies; D010033:Otitis Media / Q000188:drug therapy; D011320:Primary Health Care / Q000706:statistics & numerical data*; D012141:Respiratory Tract Infections / Q000188:drug therapy; D012874:Skin Diseases, Infectious / Q000188:drug therapy; D018461:Soft Tissue Infections / Q000188:drug therapy; D017211:Treatment Failure; D006113:United Kingdom
chemical_list: D000900:Anti-Bacterial Agents