Longitudinal Analysis of Refractive Errors in Premature Children during the First Three Years of Life

Abstract

ABSTRACT Purpose To examine the longitudinal behavior of refractive errors in both retinopathy of prematurity (ROP) and non-ROP screened premature children during the first three years of life. Methods This retrospective cohort included premature children (less than 37 weeks gestational age) born between 10/2011 and 8/2013 with ≥ two cycloplegic refractions. Cycloplegic refractions were converted into power vectors: M (spherical equivalent), J0 [positive for with-the-rule (WTR) and negative for against-the-rule (ATR) astigmatism], and J 45 (oblique astigmatism). Each power vector component was fitted by multilevel mixed-effects linear regression models; the mean change over time was analyzed. Results Mean J0 was 0.59 (95% CI 0.53–0.66) at six months and 0.29 (95% CI 0.19–0.39) at 18 months; afterward, the change was <0.1 per year. J0 decreased −0.32 (0.64 diopters) over three years. When analyzed in one-year increments, the mean change in J0 and M was lowest at 24 months. M decreased 1.13 diopters over three years. Conclusion WTR astigmatism and spherical equivalent decreased over the first three years of life. WTR astigmatism accounted for the majority of amblyopogenic refractive errors. The change in J0 leveled after 18 months and the lowest rate of change was at 24 months in J0 and M, thus it may be appropriate to screen this high-risk population around 18–24 months.