Factors associated with high myopia after 7 years of follow-up in the Correction of Myopia Evaluation Trial (COMET) Cohort.
OBJECTIVE
To evaluate factors associated with the development of high myopia (worse than -6.00 D) over 7 years of follow-up in the COMET cohort.


METHODS
COMET enrolled 469 ethnically diverse children (6-11 years) with myopia between -1.25 and -4.50 D. They were randomized to either progressive addition lenses (PALs) or single vision lenses (SVLs), and followed for 5 years in their original lens assignment and 2 additional years wearing either spectacles (PALs or SVLs) or contact lenses. Refractive error was measured annually by cycloplegic autorefraction and axial length by A-Scan ultrasonography. Myopia for each child was defined as the mean spherical equivalent refractive error (SER) of the 2 eyes. Analyses were based on 7 years of follow-up. Time to high myopia was analyzed by Cox proportional hazard models and linear regression. Parental refraction data were available from 240 COMET subjects.


RESULTS
Younger (6-7 years) versus older (11 years) age at baseline was a significant risk factor (adjusted hazard ratio (HR) = 6.6, 95% CI = 3.4, 12.7) for having high myopia within 7 years. More (SER from -2.26 to -4.50 D) vs. less (SER from -1.25 to -2.25 D) baseline myopia was also a significant risk factor for high myopia at 7 years (adjusted HR = 7.4, 95% CI = 4.4, 12.4). Gender, ethnicity, and treatment assignment were not associated with the risk of high myopia within 7 years. Increased number of myopic parents was associated with a significant risk of high myopia in the children (p = 0.008).


CONCLUSIONS
Children who developed high myopia during 7 years of follow-up were younger and had more myopia at baseline. They also were more likely to have two myopic parents. These children may be at greater risk for sight-threatening conditions later in life.
Gwiazda
Jane
J
New England College of Optometry, Boston, Massachusetts 02115, USA. gwiazdaj@neco.edu
Hyman
Leslie
L
Dong
Li Ming
LM
Everett
Don
D
Norton
Tom
T
Kurtz
Dan
D
Manny
Ruth
R
Marsh-Tootle
Wendy
W
Scheiman
Mitch
M
D002648:Child; D018450:Disease Progression; D005139:Eyeglasses; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D047728:Myopia, Degenerative / Q000209:etiology* / Q000628:therapy*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors