Minus Soft Contact Lens Power Progression in Young Myopes: A Retrospective Chart Review

Abstract

Purpose: : The purpose of this secondary analysis is to describe predictive factors associated with myopic progression in soft contact lens (SCL) power in a young population who presented for routine clinical eye care.

Methods: : A retrospective chart review of a myopic cohort from the Contact Lens Assessment in Youth (CLAY) study was analyzed for predictive factors and for SCL power progression by age. Myopes aged 8 to 22 years old who presented to all visits wearing a SCL with at least -0.50DS in the less myopic eye and with ≤ 1.00 DC in the most astigmatic eye were included. Myopic progression was defined as an increase of -0.50D SCL power in at least one eye. Data were analyzed by multivariate methods.

Results: : Myopic SCL wearers (666 experienced and 246 neophyte) were observed at 4,341 visits with mean follow-up of 24.4 months. At baseline 37% wore hydrogel (Hy) and 63% silicone hydrogel (SiHy) lenses. Significant factors to predict future myopic increases in CL power were: starting age 8 to 13 years, higher starting CL power, shorter time to first change in CL power, and lens material. The mean change in CL power over the observation period varied inversely with age, ranging from -0.40D/yr in 8-10 year olds to -0.10D/yr in 20-22 year olds (p<0.0001). Of the 551 wearers who increased in minus during the observation period, prevalence of increases of ≥ -0.50D occurred more often in moderate myopes (>-3.0D) compared with low myopes of the same age (p=0.003). There was less progression in users of SiHy materials after controlling for age (p=0.003).

Conclusions: : In this retrospective chart review of 912 contact lens wearers, baseline age between 8 and 13, higher levels of baseline myopia, use of hydrogel lens material and earlier time to first change were predictive of greater minus SCL power change. The mean rate of change in SCL power was similar to progression rates in prospective myopia clinical trials.

Keywords: contact lens • myopia • refractive error development