title: Atropine for the treatment of childhood myopia: safety and efficacy of 0.5%, 0.1%, and 0.01% doses (Atropine for the Treatment of Myopia 2).
abstract: OBJECTIVE
  Our previous study, Atropine for the Treatment of Myopia 1 (ATOM1), showed that atropine 1% eyedrops were effective in controlling myopic progression but with visual side effects resulting from cycloplegia and mydriasis. The aim of this study was to compare efficacy and visual side effects of 3 lower doses of atropine: 0.5%, 0.1%, and 0.01%.
  
  
  METHODS
  Single-center, double-masked, randomized study.
  
  
  METHODS
  A total of 400 children aged 6-12 years with myopia of at least -2.0 diopters (D) and astigmatism of -1.50 D or less.
  
  
  METHODS
  Children were randomly assigned in a 2:2:1 ratio to 0.5%, 0.1%, and 0.01% atropine to be administered once nightly to both eyes for 2 years. Cycloplegic refraction, axial length, accommodation amplitude, pupil diameter, and visual acuity were noted at baseline, 2 weeks, and then every 4 months for 2 years.
  
  
  METHODS
  Myopia progression at 2 years. Changes were noted and differences between groups were compared using the Huber-White robust standard error to allow for data clustering of 2 eyes per person.
  
  
  RESULTS
  The mean myopia progression at 2 years was -0.30±0.60, -0.38±0.60, and -0.49±0.63 D in the atropine 0.5%, 0.1%, and 0.01% groups, respectively (P=0.02 between the 0.01% and 0.5% groups; between other concentrations P > 0.05). In comparison, myopia progression in ATOM1 was -1.20±0.69 D in the placebo group and -0.28±0.92 D in the atropine 1% group. The mean increase in axial length was 0.27±0.25, 0.28±0.28, and 0.41±0.32 mm in the 0.5%, 0.1%, and 0.01% groups, respectively (P < 0.01 between the 0.01% and 0.1% groups and between the 0.01% and 0.5% groups). However, differences in myopia progression (0.19 D) and axial length change (0.14 mm) between groups were small and clinically insignificant. Atropine 0.01% had a negligible effect on accommodation and pupil size, and no effect on near visual acuity. Allergic conjunctivitis and dermatitis were the most common adverse effect noted, with 16 cases in the 0.1% and 0.5% atropine groups, and no cases in the 0.01% group.
  
  
  CONCLUSIONS
  Atropine 0.01% has minimal side effects compared with atropine at 0.1% and 0.5%, and retains comparable efficacy in controlling myopia progression.
authors.affiliation: Singapore National Eye Center, Singapore.
authors.forename: Audrey
authors.initials: A
authors.lastname: Chia
authors.forename: Wei-Han
authors.initials: WH
authors.lastname: Chua
authors.forename: Yin-Bun
authors.initials: YB
authors.lastname: Cheung
authors.forename: Wan-Ling
authors.initials: WL
authors.lastname: Wong
authors.forename: Anushia
authors.initials: A
authors.lastname: Lingham
authors.forename: Allan
authors.initials: A
authors.lastname: Fong
authors.forename: Donald
authors.initials: D
authors.lastname: Tan
mesh_terms: D000065:Accommodation, Ocular / Q000187:drug effects; D000287:Administration, Topical; D001285:Atropine / Q000008:administration & dosage* / Q000009:adverse effects; D058452:Axial Length, Eye; D002648:Child; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D009184:Mydriatics / Q000008:administration & dosage* / Q000009:adverse effects; D009216:Myopia / Q000188:drug therapy* / Q000503:physiopathology; D009883:Ophthalmic Solutions / Q000008:administration & dosage / Q000009:adverse effects; D011680:Pupil / Q000187:drug effects; D012029:Refraction, Ocular / Q000187:drug effects; D016896:Treatment Outcome; D014792:Visual Acuity / Q000187:drug effects
chemical_list: D009184:Mydriatics; D009883:Ophthalmic Solutions; D001285:Atropine