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A population-based study on the prevalence and causes of childhood blindness and visual impairment in North India
Meenakshi Wadhwani1, Praveen Vashist2, Suraj Singh Senjam2
1Department of Pediatric Ophthalmology, Chacha Nehru Bal Chikitsalya, Geeta Colony, New Delhi, India.
Insights
Visual impairment affects 5.92 per thousand children under 16 in urban North India, with refractive errors being the primary cause of avoidable vision loss. Optic nerve issues cause blindness.
Area of Science:
- Ophthalmology
- Public Health
- Pediatrics
Background:
- Visual impairment (VI) in children poses a significant public health challenge.
- Understanding the prevalence and causes of VI in pediatric populations is crucial for targeted interventions.
Purpose of the Study:
- To determine the prevalence and etiological factors of visual impairment in children under 16 years in urban North India.
Main Methods:
- A cross-sectional study involving 20,955 children aged less than 16 years across 40 clusters in urban Delhi.
- Visual acuity screening using age-appropriate charts; detailed ophthalmic examination for referred children.
- Defined criteria for referral included visual acuity <6/12 (3-15 years) or inability to follow light (<3 years).
Main Results:
- A total of 124 children had presenting visual acuity <6/18 in the better eye.
- The prevalence of visual impairment (VI) was 5.92 per thousand (95% CI: 4.96-7.05).
- Refractive errors were the main cause of avoidable VI (75.7%); optic nerve abnormalities were the leading cause of blindness (0.42 per thousand).
Conclusions:
- Refractive error is the most significant cause of avoidable visual impairment in children.
- Optic nerve abnormalities are the primary cause of blindness in this pediatric cohort.
- Addressing refractive errors is critical for reducing the burden of visual impairment in children.
Purpose:
This was a population-based study to determine the prevalence and causes of visual impairment in children less than 16 years in Urban North India.
Methods:
This cross-sectional study was conducted in 40 clusters of urban Delhi. 20,955 children aged less than 16 years underwent visual acuity screening using age-appropriate visual acuity charts. Unaided visual acuity of enumerated children aged over 2 years was assessed by using Lea symbols chart in 3-5 years age group and logMAR tumbling E charts for the 6-15 years age group. For children aged 0-2 years, fixation and following to torch light was assessed. All the children with unaided visual acuity of <6/12 in any eye in age group 3-15 years and inability to follow the light in age <3 years were referred for detailed ophthalmic examination.
Results:
Amongst 20,955 children examined for visual acuity a total of 789 children were referred to the central clinic for detailed ophthalmic examination. Of these referred children, a total of 124 had presenting visual acuity <6/18 in the better eye. The prevalence of visual impairment (VI) was 5.92 per thousand (95% CI: 4.96-7.05). The prevalence of moderate to severe visual impairment was maximum in the age group of 11 to 15 years. The main cause of avoidable VI in these children was a refractive error (75.7%). The prevalence of blindness was 0.42 per thousand.
Conclusion:
Optic nerve abnormalities were the most important cause of blindness in children. Refractive error is the most important cause of visual impairment amongst children and needs to be addressed.
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