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Refractive error in Nigerian adults: prevalence, type, and spectacle coverage
Christian Ezelum1, Hessom Razavi, Selvaraj Sivasubramaniam
1Ministry of Health, Awka, Anambra State, Nigeria.
Investigative Ophthalmology & Visual Science
|February 19, 2011
Summary
Uncorrected refractive errors significantly cause visual impairment in Nigerian adults. Improving eye care services and readily available spectacles are crucial to address this widespread need for better distance vision.
Area of Science:
- Ophthalmology
- Public Health
- Epidemiology
Background:
- Refractive errors are a major cause of visual impairment globally.
- Access to corrective eyewear is limited in many low- and middle-income countries.
- Understanding the prevalence of refractive error and spectacle use is vital for targeted interventions.
Purpose of the Study:
- To determine the prevalence and types of refractive errors in Nigerian adults aged 40 and above.
- To assess the spectacle-wearing rate among this population.
- To evaluate the potential for off-the-shelf spectacles to meet the need for distance vision correction.
Main Methods:
- A nationally representative sample of 13,599 adults aged ≥40 years was surveyed using multistage, stratified, cluster random sampling.
- Distance vision was assessed using a tumbling-E chart, followed by autorefraction.
- Participants with visual impairment underwent detailed clinical examination to determine the cause and measure corrected acuity.
Main Results:
- Uncorrected refractive error was the primary cause of mild to moderate visual impairment, accounting for 77.9% and 57.1%, respectively.
- The prevalence of myopia and high myopia was 16.2% and 2.1%, respectively.
- Spectacles could benefit approximately 2.14 million Nigerian adults, with over a third of the need potentially met by low-cost, off-the-shelf options, yet spectacle wear was low (3.4%-4.4%).
Conclusions:
- Uncorrected refractive errors represent a significant public health challenge for visual impairment in Nigeria.
- There is a substantial unmet need for distance vision correction in the adult population.
- Enhancing eye care services and improving access to affordable spectacles are essential to address this burden.
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