The impact of modest prematurity on visual function at age 6 years: findings from a population-based study.
OBJECTIVE
To determine the effects of modest low birth weight and prematurity on visual function of children predominantly aged 6 years.


METHODS
Children with a birth weight of 1500 to 2499 g were considered exposed to a modest low birth weight (n = 82) and were compared with children with a birth weight of 2500 g or more (n = 1386). Exposure to modest prematurity, 32 to 36 weeks' gestation (n = 115), was similarly analyzed and compared with birth at term, 37 or more weeks' gestation (n = 1446). Logarithm of the minimum angle of resolution visual acuity was measured in both eyes. Cycloplegic autorefraction (cyclopentolate), cover testing, and dilated fundus examinations were performed.


RESULTS
A modest low birth weight increased the risk of amblyopia (relative risk [RR], 5.1; 95% confidence interval [CI], 2.2-12.0), strabismus (RR, 3.7; 95% CI, 1.5-9.1), and anisometropia (RR, 3.7; 95% CI, 1.2-11.1), together with an increased risk of uncorrected visual acuity in the lowest quartile (RR, 1.7; 95% CI, 1.3-2.2). Modest prematurity increased the risk of amblyopia (RR, 4.5; 95% CI, 1.9-10.6), strabismus (RR, 2.6; 95% CI, 1.1-6.0), and uncorrected visual acuity in the lowest quartile (RR, 1.5; 95% CI, 1.1-2.0).


CONCLUSIONS
Modest degrees of low birth weight and prematurity may be associated with increased ophthalmic morbidity at age 6 years.
Robaei
Dana
D
Department of Ophthalmology, Centre for Vision Research, University of Sydney, Westmead Hospital, Westmead, New South Wales, Australia.
Kifley
Annette
A
Gole
Glen A
GA
Mitchell
Paul
P
D000550:Amblyopia / Q000209:etiology; D015858:Anisometropia / Q000209:etiology; D002648:Child; D005260:Female; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D012029:Refraction, Ocular; D012307:Risk Factors; D013285:Strabismus / Q000209:etiology; D014786:Vision Disorders / Q000209:etiology / Q000503:physiopathology*; D014792:Visual Acuity / Q000502:physiology*