The incidence of neuro-ophthalmic diseases in Singapore: a prospective study in public hospitals.

Purpose: To describe the incidence of neuro-ophthalmic diseases in a multi-ethnic Asian population in Singapore.

Methods: Prospective study in public hospitals in Singapore. All neuro-ophthalmic cases seen in four public sector hospitals over a 22-month period (September 2002 to June 2004) were identified using a standardized protocol. The 2004 Singapore population was used as a denominator to estimate annual incidence. The prevalence of ischemic risk factors (hypertension, diabetes, and hypercholesterolemia) among cases was compared to population data.

Results: A total of 1,356 patients with neuro-ophthalmic diseases were seen during the study period, of which 627 were new incident cases. The overall annual incidence of neuro-ophthalmic diseases was 9.81 per 100,000 (95% confidence interval, 8.80-10.90). The incidence increased with age. After controlling for age, the annual incidence was similar between men (10.75 per 100,000) and women (9.00 per 100,000), but was higher in Chinese (10.33 per 100,000) and Indians (9.34 per 100,000) than in Malays (6.62 per 100,000). The three commonest specific neuro-ophthalmic conditions were abducens nerve palsy (1.27 per 100,000), anterior ischemic optic neuropathy (1.08 per 100,000) and oculomotor nerve palsy (0.91 per 100,000). The incidence of optic neuritis was 0.83 per 100,000. Compared with the Singapore general population, the prevalence of diabetes was significantly higher in people aged 40-59, while the prevalence of hypercholesterolemia was significantly higher in 60-69 year age group.

Conclusion: In this study of public hospitals in Singapore, the incidence of neuro-ophthalmic diseases was higher in Chinese and Indians compared to Malays.