By Hamdy Amrizal BSci, BOptom
Brien Holden Vision Institute
With an increasing number of children becoming myopic and becoming more myopic, there has been an increase in the number of practitioners fitting children with contact lenses to control myopic progression. Although the evidence is clear on the effectiveness of contact lenses in slowing myopia, issues around the safety of contact lens wear remain.
In this publication, Bullimore reviewed the available literature for studies of contact lenses involving children including epidemiological studies of contact lens-related complications, hospital-based case series and prospective and retrospective studies. Nine prospective studies, accounting for 1,800 patient years of contact lens wear in patients from ages seven to 19, and two retrospective studies, accounting for 1,826 patient years of contact lens wear in patients ages six to 17, were included in the analysis as safety outcomes were reported in these studies.
None of the prospective studies encountered an event of microbial keratitis. The multi-center retrospective study (The Contact Lens Assessment in Youth (CLAY) Study) reported two incidents of microbial keratitis in patients ages 13 to 17, representing an incidence of microbial keratitis of 15 per 10,000 patient years, comparable to that of adults. No incidents of microbial keratitis were reported in patients from eight to 12 years old. Considering infiltrative events, data from long term prospective studies where data on adverse events in children were published, rates of symptomatic corneal infiltrative events varied with up to 136 per 10,000 patient years and was substantially lower for comparable data from adult contact lens wearers. These figures are also comparable to the data reported from the CLAY study, wherein 187 corneal infiltrative events were noted in patients under the age of 18. Age was a significant risk factor for developing CIEs – age-related risk profiles were the safest in patients eight to 12 years old (97 per 10,000 patient years) followed by those 13 to 17 (335 per 10,000 patient years). Comparatively, in adults, the incidence of symptomatic CIEs ranges from 316-2,061 per 10,000 patient years dependent on the modality of wear and material of the contact lens.
Overall, the article gathers evidence that demonstrates that the incidence of corneal infiltrative events in children is no higher than in adults, and in the youngest age range of 8 to 11 years, it could be lower. This may be due to a higher percentage of daily disposable and part-time wearers, parental supervision or reduced risk-taking behavior such as sleeping in contact lenses.
The Safety of Soft Contact Lenses in Children
Bullimore, M. A.
There is increasing interest in fitting children with soft contact lenses. This review collates data from a range of studies to estimate the incidence of complications, specifically corneal infiltrative events and microbial keratitis, in patients under the age of 18.
Peer-review papers were identified using PubMed and the Web of Science. A broad range of studies are summarized, including large-scale epidemiological studies of contact lens-related complications, hospital-based case series, long- and short-term prospective studies, and multicenter retrospective studies.
Nine prospective studies representing 1,800 years of wear in patients seven to 19 years include safety outcomes. In three large prospective studies representing between 159 and 723 patient years of soft contact lens wear in patients age eight to 14, the incidence of corneal infiltrative events is up to 136 per 10,000 years. Data from a large retrospective study show similar rates of corneal infiltrative events: 97 per 10,000 years in patients eight to 12 years old, (based on 411 patient years of wear) and 335 per 10,000 years in those 13 to 17 (based on 1,372 patient years of wear). None of the prospective studies report any cases of microbial keratitis. Five clinical studies where safety data are not reported constitute a further 493 patient years. One retrospective study found no cases of microbial keratitis occurred in patients ages eight to 12 (411 patient-years) and an incidence of 15 per 10,000 patient years in patients 13 to 17 (1,372 patient years)—no higher than the incidence of microbial keratitis in adults wearing soft contact lenses on an overnight basis.
The overall picture is that the incidence of corneal infiltrative events in children is no higher than in adults, and in the youngest age range of eight to 11 it may be markedly lower.
Bullimore, M. A. (2017). The safety of soft contact lenses in children. Optometry and Vision Science, 94(6), 638.