Influence of topical ocular atropine on long-term progression of myopia

Myopia represents an important public health problem because it affects approximately 25% of the population of the United States and it is associated with increased risk for retinal detachment and other vision threatening abnormalities. Studies of animals have shown that environmental factors, especially deprivation of pattern vision can lead to the development of myopia. In some species, myopia progression can be decreased with atropine treatment. The purpose of this study was to provide information regarding the safety of atropine and the long-term effects of treatment on progression of myopia in humans. A total of 214 residents of Olmsted County, Minnesota (118 girls and 96 boys) were treated with atropine for myopia from 1967 through 1974. The ages ranged from 6 to 15 years (median, 11 years). Control subjects were matched by age, gender, refractive error, and date of examination to 194 of the atropine-treated patients. Duration of treatment with atropine ranged from 18 weeks to 11.5 years (median, 3.5 years). Photophobia and blurred vision were frequently reported, but no serious adverse effects were associated with atropine therapy. A total of 1,793 refractions were performed on the atropine-treated subjects and 1,183 on the controls during the study period. Median follow-up from initial to last refraction in the atropine group (12.8 years) was similar to that among the controls (13.1 years). Random effects maximum likelihood multiple regression analyses showed that age and refractive error were important covariates (P {dollar}{dollar} 0.05). Mean myopia progression during atropine treatment adjusted for age and refractive error (0.05 diopters per year) was significantly less than that during a comparable period among the controls (0.36 diopters per year) (P {dollar}<{dollar} 0.001). Final refractions standardized to the age of 20 years showed a greater mean level of myopia among controls (3.75 diopters) than in the atropine group (2.86 diopters) (P {dollar}<{dollar} 0.001). The data support the view that atropine therapy is associated with decreased progression of myopia, and that beneficial effects remain after treatment has been discontinued.