Developmental Changes in Anterior Corneal Astigmatism in Tohono O’odham Native American Infants and Children

ABSTRACT

Purpose: To describe change in corneal astigmatism in infants and children of a Native American tribe with a high prevalence of astigmatism.

Methods: Longitudinal measurements of corneal astigmatism were obtained in 960 Tohono O’odham children aged 6 months to <8 years. Change in corneal astigmatism (magnitude (clinical notation), J0, J45) across age in children with high astigmatism (≥2 diopter (D) corneal astigmatism) or low/no astigmatism (<2 D corneal astigmatism) at their baseline measurement was assessed.

Results: Regression analyses indicated that early in development (6 months to <3 years), astigmatism magnitude decreased in the high astigmatism group (0.37 D/year) and remained stable in the low/no astigmatism group. In later development (3 to <8 years), astigmatism decreased in the high (0.11 D/year) and low/no astigmatism groups (0.03 D/year). In 52 children who had data at all three of the youngest ages (6 months to <1 year, 1 to <2 years, 2 to <3 years) astigmatism decreased after infancy in those with high astigmatism (p = 0.021), and then remained stable from age 1–2 years, whereas astigmatism was stable from infancy through age 1 year and increased from age 1–2 years in the low/no astigmatism group (p = 0.026). J0 results were similar, but results on J45 yielded no significant effects.

Conclusions: The greatest change occurred in highly astigmatic infants and toddlers (0.37 D/year). By age 3 years, change was minimal and not clinically significant. Changes observed were due primarily to change in the J0 component of astigmatism.

• Astigmatism
• children
• longitudinal
• native American
• refractive error

ACKNOWLEDGEMENTS

The authors thank the Tohono O’odham Nation, the Tohono O’odham Early Childhood Head Start Program, the Baboquivari School District, the Bureau of Indian Affairs Office of Indian Education Programs, the San Xavier Mission School, the parents and children who participated in the study, and our NIH/NEI Data Monitoring and Oversight Committee (Robert Hardy, PhD (chair), Donald Everett, MA, Jonathan Holmes, MD, Ronald Johnson, MD, Andrew Lorentine, Rosemary Lopez, and Karla Zadnik, OD, PhD).

Notes

*This research was presented in part at the Association for Research in Vision and Ophthalmology Annual Meeting, May 6, 2012.