Increased time spent outdoors during childhood is known to dampen the progression of myopia, but mitigating against this advantage of the great outdoors is concern over exposure to ultraviolet light—including its effect on refractive status. After observing refractive changes in wearers of soft contact lenses over a five-year period, a large epidemiologic study in Japan found that UV exposure might be a risk factor for myopia progression. Patients who wore UV blocking lenses over time appear to have less myopia progression both by sex and degree of myopia. The researchers will present their findings at ARVO 2019 tomorrow morning.
The study tracked changes in refraction in 57,135 eyes of patients between the ages of 12 and 15 that had been prescribed UV-protected contact lenses (n=35,734) or lenses without UV protection (n=21,401). Regarding myopia, patients were classified into two groups based on the lens power prescribed: medium myopia (between -6.00D and -3.00D) and low myopia (between -3.00D and -0.25D).
For men, myopia progression was significantly more common in eyes without UV protection (-1.106D in SCL with UV protection and -1.150D in lenses without UV protection). For women, progression was also significantly greater in eyes without UV protection (–1.127D with UV protection and -1.147D without).
For both medium and low myopia patients, progression was more rapid in patients who lacked UV protection. In eyes classified as medium myopia, changes in patients with and without UV protection were -1.056D and -1.092D, respectively. For low myopia eyes, changes were -1.176D and -1.204D, respectively.
“The Asian population has a high prevalence of high myopia, and these interesting findings and information from Japan could be transferable to other populations,” notes Joseph Shovlin, OD, of Northeastern Eye Institute in Scranton, PA. “Considering UV protection may be one more way that practitioners may be able to help control for myopia, at least in a modest fashion.”
|Yoshida M, Mizuki N, Takeuchi M, et al. A large-scale, epidemiologic study of the influence of ultraviolet exposure on myopia progression—a 5-year follow-up study of approximately 57,000 Japanese patients' eyes. ARVO 2019. Abstract 6347.|