Ethnic variations in the incidence and outcome of severe retinopathy of prematurity

BACKGROUND: The aim of this study was to assess the incidence and outcome of severe retinopathy of prematurity (ROP) among different ethnic groups in a geographically defined population in the U.K. Severe ROP was defined as any stage 3 or worse disease. METHODS: This was a retrospective study of children born over a 6-year period with a birth weight of 1250 g or less. Threshold ROP was treated with diode laser. RESULTS: Severe disease developed in 37 out of 355 neonates (10.4%) who underwent ROP screening. The difference in the incidence of severe ROP between infants of Caucasian and South Asian ethnic origin was not statistically significant: 10.2% vs. 10.8% (odds ratio = 1.06; 95% confidence interval: 0.44 to 2.57). This conclusion held after single-variable adjustment for birth weight, gestational age, and score on the Clinical Risk Index for Babies. The incidence of threshold ROP was 3% among infants of both Caucasian and South Asian ethnic origin. There was no significant difference in terms of visual outcome between the Caucasian and South Asian infants. INTERPRETATION: This study showed no statistical evidence for a difference in the incidence or outcome of severe ROP among infants of South Asian ethnic origin compared with those of Caucasian origin. Although the small numbers in our study mean that a clinically important difference cannot be excluded, it is very unlikely that the 5-fold higher incidence in Asian babies described in the literature is correct for the population from which our subjects were drawn.