title: Trends in age-related macular degeneration management in Singapore.
abstract: OBJECTIVE
  To describe the trends and patterns of anti-vascular endothelial growth factor (anti-VEGF) therapy and photodynamic therapy (PDT) use for age-related macular degeneration (AMD) in the National Eye Centre in Singapore over a 4-year period.
  
  
  METHODS
  Data on the total number of intravitreal anti-VEGF injections and PDT treatment over a 4-year period at the Singapore National Eye Centre were obtained from centralized electronic records. Patients aged 40 years and older treated for AMD were included. Data retrieved included the annual treatment load in terms of number of new patients and total treatment episodes, and treatment burden for patients was studied in terms of number of injections per year and cumulative injection numbers over 3 years. Potential influence on retreatment by choice of drug, use of adjunct PDT, and diagnosis of polypoidal choroidal vasculopathy were further analyzed.
  
  
  RESULTS
  From 2009 to 2012, a total of 6157 injections were performed on 1380 unique individual patients. The total number of injections performed per calendar year increased from 962 in 2009 to 2278 in 2012. The number of unique incident cases increased from 287 in 2009 to 446 in 2012. The mean number of injections over the first year increased from 2.62 in 2009 to 3.19 in 2012 (p < 0.001). Choice of anti-VEGF therapy did not significantly alter the cumulative injections required. Patients diagnosed as having polypoidal choroidal vasculopathy had similar injection episodes (p = 0.178), whereas choice of anti-VEGF and adjunct PDT had no effect on the overall treatment.
  
  
  CONCLUSIONS
  Anti-VEGF treatment of AMD continues to increase substantially year on year in the past few years, in alignment with experience from other countries. However, the cumulative number of injections per patient remains low, and many patients discontinue treatment within the first year. These data demonstrate that undertreatment remains a significant concern in clinical settings.
authors.affiliation: *MBBS †FRCOphth ‡FRCSE §FRCSE, PhD Singapore National Eye Centre, Singapore, Singapore (all authors); Singapore Eye Research Institute, Singapore, Singapore (CMGC, TYW); Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore (CMGC, TYW); and Ophthalmology Academic Clinical Program, Duke-NUS Graduate Medical School, Singapore, Singapore (CMGC, TYW).
authors.forename: Wei Yan
authors.initials: WY
authors.lastname: Ng
authors.forename: Chui Ming Gemmy
authors.initials: CM
authors.lastname: Cheung
authors.forename: Ranjana
authors.initials: R
authors.lastname: Mathur
authors.forename: Choi Mun
authors.initials: CM
authors.lastname: Chan
authors.forename: Ian Yew San
authors.initials: IY
authors.lastname: Yeo
authors.forename: Edmund
authors.initials: E
authors.lastname: Wong
authors.forename: Shu Yen
authors.initials: SY
authors.lastname: Lee
authors.forename: Boon Kwang
authors.initials: BK
authors.lastname: Loh
authors.forename: Doric
authors.initials: D
authors.lastname: Wong
authors.forename: Tien Yin
authors.initials: TY
authors.lastname: Wong
mesh_terms: D000368:Aged; D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D000068258:Bevacizumab; D002829:Choroid / Q000098:blood supply; D015862:Choroid Diseases / Q000188:drug therapy; D004363:Drug Utilization / Q000639:trends*; D005260:Female; D006801:Humans; D058449:Intravitreal Injections; D008297:Male; D010778:Photochemotherapy / Q000639:trends*; D011127:Polyps / Q000188:drug therapy; D000069579:Ranibizumab; D019233:Retreatment; D012189:Retrospective Studies; D012846:Singapore / Q000453:epidemiology; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors; D057135:Wet Macular Degeneration / Q000188:drug therapy* / Q000453:epidemiology
chemical_list: D020533:Angiogenesis Inhibitors; D061067:Antibodies, Monoclonal, Humanized; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab; D000069579:Ranibizumab