Myopia guide

Myopia risk

Unravelling the puzzle of what causes short-sightedness


The starting point for treating any condition is to understand what is causing it to develop in the first place. Although much research has accrued on the topic, there are still unanswered questions about what causes myopia. As Professor Kathryn Saunders notes: “With every new piece of information gained through research, we create more questions that are yet to be resolved.”

Kathryn Saunders
Professor Kathryn Saunders

Eye care practitioners can use tools like the Predicting Myopia Onset risk indicator (see below) to assess a child’s likelihood of becoming myopic. Saunders highlights that myopia is not simply a genetic condition.Research during the past three decades has supported the idea that the environment a child grows up in has a strong influence on how a child’s eyes grow.

“For example, light exposure appears to influence eye growth and therefore there are strong links between childhood myopia and spending less time outdoors where light levels are higher.”

Studies have also found a link between additional years in education and levels of myopia. As a result, some researchers hypothesise there may be a link between near work and myopia. However, Saunders notes that this could also be explained by the large amounts of time spent indoors that studying involves.

With every new piece of information gained through research, we create more questions

Professor Kathryn Saunders

She added that there is emerging evidence suggesting that poor sleep quality and/or disrupted circadian rhythms could influence refractive outcomes and potentially promote myopic growth.

“It is easy to see how our modern lifestyles and environments don’t exactly promote healthy circadian rhythms – perhaps this is also contributing to the rapid increase in prevalence of earlier onset myopia in modern children.”

Further reading on myopia management, including the topics discussed above, can be found on the OT website.