Prevalence of corneal astigmatism in Tohono O'odham Native American children 6 months to 8 years of age

• Published in: Investigative ophthalmology & visual science Vol. 52; no. 7; pp. 4350 - 4355
• Main Authors: Harvey, Erin M, Dobson, Velma, Miller, Joseph M, Schwiegerling, Jim, Clifford-Donaldson, Candice E, Green, Tina K, Messer, Dawn H
• Format: Journal Article
• Language: English
• Published: United States Association for Research in Vision and Ophthalmology, Inc 21-06-2011
• Subjects: Arizona - epidemiology; Astigmatism - ethnology; Astigmatism - physiopathology; Child; Child, Preschool; Female; Follow-Up Studies; Humans; Indians, North American; Infant; Male; Prevalence; Refraction, Ocular - physiology; Retrospective Studies; Visual Acuity; Arizona
• ISSN: 1552-5783; 0146-0404; 1552-5783
• DOI: 10.1167/iovs.10-6061

To describe the prevalence of corneal astigmatism in infants and young children who are members of a Native American tribe with a high prevalence of refractive astigmatism.
The prevalence of corneal astigmatism was assessed by obtaining infant keratometer (IK4) measurements from 1235 Tohono O'odham children, aged 6 months to 8 years.
The prevalence of corneal astigmatism >2.00 D was lower in the 1- to <2-year-old age group when compared with all other age groups, except the 6- to <7-year-old group. The magnitude of mean corneal astigmatism was significantly lower in the 1- to <2-year age group than in the 5- to <6-, 6- to <7-, and 7- to <8-year age groups. Corneal astigmatism was with-the-rule (WTR) in 91.4% of astigmatic children (≥1.00 D).
The prevalence and mean amount of corneal astigmatism were higher than reported in non-Native American populations. Mean astigmatism increased from 1.43 D in 1-year-olds to nearly 2.00 D by school age.