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Parameters associated with the different astigmatism axis orientations.

Yossi Mandel¹, Richard A Stone, David Zadok

¹Israel Defense Force Medical Corps Headquarters, Ramat-Gan, Israel. yossimandel@bezeqint.net

Investigative Ophthalmology & Visual Science

|October 3, 2009

Summary

This summary is machine-generated.

Astigmatism axis orientation is linked to various factors including intelligence, body mass index, and perinatal photoperiod. These associations differ across astigmatism types, suggesting distinct developmental mechanisms.

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Area of Science:

Ophthalmology
Genetics
Human Biology

Background:

Astigmatism is a common refractive error affecting visual acuity.
Understanding the factors influencing astigmatism axis orientation is crucial for comprehending its etiology.
Previous research has explored various associations, but a comprehensive analysis of astigmatism axis orientation is needed.

Purpose of the Study:

To investigate parameters associated with astigmatism axis orientation in a large population.
To identify demographic, anthropometric, and environmental factors correlated with different astigmatism axis orientations.

Main Methods:

Retrospective population-based study of 67,899 Israeli Defense Force conscripts (age 16-22) with astigmatism.
Data included prerecruitment examination, demographic information, general intelligence scores, and refractive error classification using the least deviation from emmetropia (LDE) scheme.
Perinatal photoperiod was determined from birth date and astronomical data.

Main Results:

With-the-rule (WTR) astigmatism was associated with higher LDE, higher cylinder power, specific origins, higher body mass index, lower intelligence scores, and longer perinatal photoperiod (univariate analysis).
Multivariate analysis confirmed these associations and identified female sex as linked to WTR astigmatism.
Sibling's astigmatism axis was also a significant predictor (OR=1.58). Associations varied between WTR, against-the-rule, and oblique astigmatism.

Conclusions:

Distinct mechanisms likely underlie different astigmatism axis orientations.
Factors influencing astigmatism development may differ from those affecting the spherical component of refraction.