Optic neuropathy endemic in secondary school children in Dar es Salaam, Tanzania

• Published in: British journal of ophthalmology Vol. 94; no. 2; p. 146
• Main Authors: Bowman, R J C, Wedner, S, Bowman, R F, Masanja, H, Bunce, C, Wood, M L, Gilbert, C
• Format: Journal Article
• Language: English
• Published: England 01-02-2010
• Subjects: Adolescent; Child; Educational Status; Endemic Diseases; Female; Health Surveys; Humans; Male; Optic Nerve Diseases - complications; Optic Nerve Diseases - epidemiology; Prevalence; Socioeconomic Factors; Tanzania - epidemiology; Vision Disorders - epidemiology; Vision Disorders - etiology; Visual Acuity; Young Adult; Tanzania
• ISSN: 1468-2079
• DOI: 10.1136/bjo.2009.160713

To investigate the prevalence and causes of optic neuropathy, reported as epidemic in 1997, among secondary school students in Dar es Salaam, Tanzania.
First year students (n = 10,892) from 63 secondary schools located within 30 km from the base hospital were interviewed and had a visual acuity (VA) screening test. Students failing the 6/12-line in either eye were defined as having "poor eyesight" and referred to the base hospital where an optometrist re-tested VA and refracted them. An ophthalmologist examined students with VA of 6/12 or worse in either eye and visual impairment was defined as VA of worse than 6/12 with best correction. Associations between optic neuropathy, socioeconomic status and educational results were investigated.
Students' ages ranged from 12 to 22 (mean 15.2) years; 50.6% were male. The prevalence of optic neuropathy was 0.3 (SD 0.051)%. The condition affected older students and was associated with the family having fewer economic possessions (car, computer, television). Optic neuropathy accounted for 19/33 (58%) of bilateral visual impairment cases. No effect of the disease on educational performance was identified.
Optic neuropathy remains a significant problem in this population and can now be termed endemic rather than epidemic. Further research into its causes is required.