Myopia also known as short-sightedness, is a refractive error, where the shape of your eye does not bend light correctly, resulting in blurred distant vision. According to the World Health Organization (WHO), myopia already affects about 30 per cent of the world’s population. In Australia and New Zealand, the myopic population is estimated to reach 22 million by the year 2050, up from 4 million in the year 2000.
What does this mean for Australian children?
Myopia affects around two per cent of Australian children (107,710) and is the most common visual impairment for people under the age of 18. Uncorrected myopia is the leading cause of poor visual acuity. Myopia typically develops at approximately eight years of age and progresses through adolescence. The nature versus nurture argument applies to myopia, with both genetics and environmental factors playing a part in the development of myopia. Parents who are myopic are encouraged to have their children assessed at an early age to encourage early intervention. The average rate of progression is approximately 0.50 D (dioptre) per year. Studies have found that near activities can lead to both the onset and progression of myopia. Seven or more hours of screen time per week triples the risk for myopia. It is not only the screen time to blame, even children who read more than two books a week triple their risk of developing myopia. The increased risk of myopia associated with near activities such as reading and screen time is thought to be possibly also be associated with the reduced exposure to sunlight.
The good news:
Outdoor time offers a protective effect for the onset and progression of myopia. It is recommended that children spend 15 hours outside weekly, or 2-3 hours each school day, to prevent myopia. Even a 50 per cent reduction in myopia progression significantly reduces the risks of myopia-related eye diseases, many of which can lead to permanent vision loss.