High Add Power Multifocal Contact Lenses Slow Myopia Progression in Children

In children, high add power multifocal contact lenses significantly reduced the rate of myopia (nearsightedness) progression over 3 years compared with medium add power and single-vision lenses. Results of the randomized clinical trial were published in JAMA.

The global prevalence of myopia is projected to increase from 23% to 54% between 2000 and 2050, according to data analyzed in 2016, while the prevalence of high myopia is projected to increase from 3% to 10%. Children in the United States typically develop myopia between ages 8 and 10 and the condition can progress through age 16.

“Myopia is associated with sight-threatening ocular sequelae, such as cataracts, retinal detachment, glaucoma, and choroidal atrophy,” authors wrote. “Effective myopia control measures should therefore be implemented to reduce the risks associated with increasing myopia prevalence and high societal costs.”

Current treatment for nearsightedness includes single-vision glasses or contact lenses, orthokeratology, soft multifocal contact lenses, and low-concentration atropine. However, one modifiable risk factor for the condition’s progression is the optical profile of the eye; specifically focusing light in front of the retina to slow human eye growth, researchers wrote.

“Soft multifocal contact lenses provide clear vision by focusing some light on the retina while simultaneously focusing some light in front of the retina to slow eye growth,” while “higher add power contact lenses focus light further in front of the retina and may lead to slower myopia progression than medium add power and non-multifocal contact lenses.”

In the Bifocal Lenses In Nearsighted Kids (BLINK) study, participants were randomized to wear single-vision (non-multifocal) contact lenses, medium or high add power soft multifocal lenses for 3 years.

Between September 2014 and June 2016 294 children (mean age [SD] 10.3 [1.2] years) were recruited from Houston, Texas and Columbus, Ohio to participate in the study. All follow-ups were completed by June 24, 2019.

At baseline, all participants had myopia of −0.75 to −5.00 diopter (D) (spherical component by cycloplegic autorefraction), astigmatism less than 1.00 D cylinder, best-corrected visual acuity (BCVA) of 20/25 or better in each eye, and binocular visual acuity of +0.1 logMAR (20/25) or better with +2.50 D add power soft multifocal contact lenses.

Patients were randomized 1:1:1 to wear single-vision lenses (n = 98), medium add power (+1.50 D) (n = 98) or high add power (+2.50 D) (n = 98) soft multifocal contact lenses. All soft multifocal contact lenses used in the study are commercially available.

Analyses of 292 (99%) patients found:

• Adjusted 3-year myopia progression was −0.60 D for high add power, −0.89 D for medium add power, and −1.05 D for single-vision contact lenses
• The difference in progression was 0.46 D (95% CI, 0.29-0.63) for high add power vs single vision, 0.30 D (95% CI, 0.13-0.47) for high add vs medium add power, and 0.16 D (95% CI, −0.01 to 0.33) for medium add power vs single vision
• Adjusted mean eye growth was 0.42 mm for high add power, 0.58 mm for medium add power, and 0.66 mm for single vision
• The difference in eye growth was −0.23 mm (95% CI, −0.30 to −0.17) for high add power vs single vision, −0.16 mm (95% CI, −0.23 to −0.09) for high add vs medium add power, and −0.07 mm (95% CI, −0.14 to −0.01) for medium add power vs single vision
• The percentage of participants who progressed −1.00 D or more during the study was 16.8% (95% CI, 9.9%-25.9%) for the high add power group, 36.5% (95% CI, 26.9%-46.9%) for the medium add power group, and 51.0% (95% CI, 40.6%-61.4%) for the single-vision group

No serious ocular adverse events were reported throughout the study window while the most commonly reported adverse events were papillary conjunctivitis, infiltrative keratitis, and ocular allergies.

“Greater amounts of myopia and longer eyes are associated with increased prevalence of eye conditions that can lead to visual impairment,” said study author David A. Berntsen, OD, PhD. “Our study shows that eye care practitioners should fit children with high-add power multifocal contact lenses in order to maximize myopia control and the slowing of eye growth.”

Although findings show high add power multifocal contact lenses significantly reduced the rate of myopia progression over 3 years in children with myopia, the duration of the study did not allow for measurement of the patients’ ultimate myopia, marking a limitation. Researchers noted an additional 3-year extension where all participants wear high add power lenses will allow for examination of the rebound effect.

“Further research is needed to understand the clinical importance of the observed differences,” authors concluded.

Reference:

Walline JJ, Walker MK, Mutti DO, et al. Effect of high add power, medium add power, or single-vision contact lenses on myopia progression in children. JAMA. 2020;324(6):571-580. doi:10.1001/jama.2020.10834