title: Trends over time and geographical variation in rates of intravitreal injections in England.
abstract: OBJECTIVE
  The recent emergence of antivascular endothelial growth factor (anti-VEGF) drugs has led to increased numbers of patients undergoing intravitreal injection for age-related macular degeneration (AMD). The aims of this study were to report on trends over time and geographical variation in intravitreal injection rates in England, and consider the implications for publicly funded health services of introducing new and expensive treatments.
  
  
  METHODS
  Hospital episode statistics were analysed for annual treatment rates of intravitreal injection between the NHS financial years of 1989/1990 and 2008/1999.
  
  
  RESULTS
  Annual injection rates increased from 0.4 episodes (95% CI 0.37 to 0.49) per 100,000 population in 1989/1990 to 10.7 (10.4-11.0) in 2006/2007. Rates then rose exponentially to 59.5 (58.8-60.2) in 2008/2009, with increasing use of multiple injections per person. The largest growth in injection rates was found in older people, and for AMD. Numbers of treatment episodes increased from 203 (1989/1990) to 30,458 (2008/2009). Geographical analysis showed a very wide variation across local authority areas in injection rates, from 0.9 (0.2-2.2) to 42.2 (38.9-45.7) people per 100,000 population in 2005-2008.
  
  
  CONCLUSIONS
  Rates of intravitreal injection increased exponentially from 2006/2007. This followed the US Food and Drug Association licensing of ranibizumab for the treatment of neovascular AMD (2006), and its recommendation by National Institute for Health and Clinical Excellence (2008). This study demonstrates some of the major issues which arise with the emergence of expensive new treatments, including speed and cost of adoption, geographical variation in access, and implications for licensing, commissioning and health financing in an ageing society.
authors.affiliation: School of Biomedicine, Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK. tiarnan.keenan@doctors.org.uk
authors.forename: Tiarnan D L
authors.initials: TD
authors.lastname: Keenan
authors.forename: Clare J
authors.initials: CJ
authors.lastname: Wotton
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Goldacre
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage* / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D004739:England / Q000453:epidemiology; D005843:Geography; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D058449:Intravitreal Injections / Q000639:trends*; D008268:Macular Degeneration / Q000188:drug therapy* / Q000453:epidemiology*; D008875:Middle Aged; D017678:Sex Distribution; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors
chemical_list: D020533:Angiogenesis Inhibitors; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A