Determinants of myopia among Omani school children: a case-control study

Our aim was to determine risk factors for myopia in students of 10th grade of eight regions of Oman.

This was a case control study. Students of 10th grade with and without myopia were cases and controls respectively. In 2002 to 2003, their vision, refractive status, and physical measurements were recorded. The health records of all students were reviewed for their ocular and physical status in the 7th grade. The association of myopia to anthropometric variables, "Protein Energy Malnourishment" status, gender, history of myopia in parents and sibling, trachoma, and allergic conjunctivitis were analyzed.

Myopia in students was significantly associated to myopia in parents [OR = 2.11 (95% CI 1.8-2.47)] and their siblings [OR = 2.87 (95% CI 2.45-3.35)]. Height was significantly higher in myopes compared to non-myopes both at the 10th and 7th grades. Weight and body mass index were greater in myopes than non-myopes only at 7th grade. Myopia in parents and siblings and female gender were predictors of myopia in the students.

Hereditary and anthropometric factors seem to be associated with myopia in Omani children. The genetic etiology needs further confirmation.