Your risk of contracting a rare eye infection increases almost fourfold when you use soft reusable contact lenses compared to soft disposable lenses. Those are the bleak findings of research led by University College London (UCL) Institute of Ophthalmology and Moorfields Eye Hospital, in which researchers looked at what factors can increase a person’s risk of being diagnosed acanthamoeba Keratitis (AK).
“In recent years we have seen an increase in acanthamoeba keratitis in the UK and Europe, and while the infection is still rare, it is preventable and warrants a public health response,” lead researcher Professor John Dart said in a statement.
“Contact lenses are generally very safe but carry a low risk of microbial keratitis, most commonly caused by bacteria and the only sight-threatening complication of their use. With an estimated 300 million people wearing contact lenses around the world, it is important that people know how to minimize their risk of developing keratitis.”
Dart and colleagues recruited over 200 patients, 83 of whom had AK, while the other 122 were referred to Moorfields Eye Hospital for other conditions. The latter acted as a control group so the researchers could find out which risk factors increase the likelihood of corneal infection.
Their results showed that reusable soft contact lens wearers were 3.8 times more likely to develop AK compared to disposable lens wearers. Sleeping and showering with contact lenses also increased risk by 3.9 and 3.3 times, respectively. According to their estimates, the researchers found that 30 to 62 perfect AK cases in the UK could be prevented by switching to daily lenses, which could be the case in other countries as well.
“Previous studies have linked AK to wearing contact lenses in hot tubs, pools, or lakes, and here we added showering to that list to emphasize that contact with water should be avoided while wearing lenses,” said first author , Associate Professor Nicole Carnt from the University of New South Wales, Sydney and UCL Institute of Ophthalmology and Moorfields Eye Hospital. “Public pools and coastal authorities could help reduce this risk by discouraging swimming with contact lenses.”
Although vision loss from AK is rare, it can occur in severe cases, so the team wanted to further investigate potential risk factors. In the UK, around 1 in 20,000 contact lens wearers is diagnosed with AK each year, but the team hope simple interventions could help bring that statistic down.
“Contact lens packaging should have information on lens safety and risk avoidance, even as simple as ‘no water’ stickers on every box, especially given that many people buy their contact lenses online without having spoken to a doctor ‘ Dart concluded.
“Basic contact lens hygiene measures can go a long way in preventing infection, e.g. B. by washing and drying hands thoroughly before inserting the lenses.”
The paper is published in Opthalmology.