Relationship Between Consanguineous Marriages and Incidence and Severity of Refractive Errors: A Cross-sectional Study

Congenital and genetic ocular disorders are linked to parental consanguinity. The aims was to investigate the effects of consanguineous marriages on the refractive errors of preschool-aged and adolescent patients. Two sample groups were recruited: the preschooler group (3–6 years; 335 participants) and the adolescent group (12–20 years; 998 participants). The required sample size was calculated using a sample size estimation software. Visual acuity was measured using the 15-line Lea symbols chart in the pre-school aged group and non-illuminated ETDRS VA chart in the adolescent group. Spherical equivalent refractive errors were noted with near-retinoscopy technique in young children and with the ARK-30 autorefractor in the adolescent group. In order to explore the impact of consanguineous marriages, the data were analyzed separately based on the age group using SPSS version 21 software. In the preschooler group, myopia was found in 4.2%, hyperopia in 8.1%, and astigmatism in 20%. Three children had high myopic scores (-10.00 D, -13.50 D and -17.50 D). In the adolescent group, 45.6% participants were myopic, 3.8% were hyperopic, and 22.3% were astigmatic. Despite the higher frequency of RE in those 15 years and older in the cousins group and the consanguineous parents of the three preschool-aged children with high myopia, there were no statistically significant (p>0.05) evidence that consanguineous marriages impact the refractive errors of their children. In conclusion, despite previous studies showing a link between ocular genetic or congenital disorders and consanguinity, no such link could be established with regard to refractive errors.