The prevalence and causes of visual impairment among children in Kenya – the Kenya eye study
Abstract/ Overview
Background: Visual impairment is the partial or complete loss of vision in which the presenting visual acuity lie
between 6/18-no perceptions of light. In Kenya, little attention has been directed towards children vision and
causes of visual impairment. Therefore, this study was designed to investigate the prevalence and causes of visual
impairment in the children population of Kenya.
Methods: This cross-sectional population-based study included 3400 (1800, 52.9% female) randomly selected
children with a mean age of 12 ± 2 years (range 5–16 years). Visual acuity was taken using Snellens chart at 6 m.
Anterior and posterior segment was assessed using slit lamp and indirect ophthalmoscope. The World Health
Organization definition formed the baseline for calculating the mean prevalence of visual impairment.
Results: Visual acuity measurements were available for 3240 (95.3%) participants. The mean prevalence of visual
impairment based on pin-hole value was 1.7 ± 0.3% using World Health Organization definition. The prevalence of
visual impairment based on presenting visual acuity value was 2.4 ± 0.7% using the World Health Organization
definition. Multivariate analysis demonstrated that the presence of visual impairment on pin-hole increased
significantly with increasing age (odds ratio 1.230, P = .021) and uncorrected refractive error (odds ratio 0.834,
P = .032) according to World Health Organization definition. Cases of uncorrected refractive error remained the
major cause for presenting visual impairment. Causes of visual impairment due to presenting visual acuity were
nystagmus (14%), amblyopia (24%) and uncorrected refractive error (62%).
Conclusion: The prevalence of visual impairment in Kenya is associated with age. Uncorrected refractive error
remains the major causes of visual impairment.