Keratoconus in Asians: demographics, clinical characteristics and visual function in a hospital-based population.

BACKGROUND

To describe the demographics, clinical characteristics and visual function of Asian patients with keratoconus managed in a tertiary eye centre.

DESIGN

Prospective cross-sectional study.

PARTICIPANTS

116 patients with clinically evident or suspected keratoconus (on videokeratography) recruited over 11 months.

METHODS

A standardised interview, full ophthalmic examination, refraction and corneal topography were performed. Visual function was assessed with the VF-14 questionnaire.

MAIN OUTCOME MEASURES

Demographics, clinical characteristics and visual function.

RESULTS

Mean age of our patients was 29.5 ± 9.40 years on enrolment, 62.9% were male, and the ethnic distribution was 60.3% Chinese, 13.8% Malays and 9.5% Indians. Clinically evident keratoconus was present bilaterally in 65 patients (56.0%) and unilateral keratoconus in five patients (4.3%). Five patients (4.3%) had a family history of keratoconus. The majority of patients were managed with contact lenses (60.8%) or glasses (24.5%). Eye rubbing was common (68%) as were asthma (26.3%) and eczema (18.4%). Conical protrusion was the commonest sign (75.3%). The mean cylinder was higher in keratoconus eyes compared with keratoconus suspect eyes (-4.01 vs. -1.27, P < 0.001), and best-corrected visual acuity was poorer (0.19 vs. 0.05, P < 0.001). Unaided visual acuity was significantly worse with increasing age (P = 0.016). On the VF-14, 32% scored 90 or less (out of 100), reflecting difficulties with vision-related daily activities.

CONCLUSIONS

Our Asian patients with keratoconus had similar demographic and clinical characteristics to patients in Western populations. Even with apparently good visual acuity, some patients still experience substantial impairment in vision-related activities.