Abstract
Purpose::
Because the etiology of most cases of infantile cataracts is unknown, the scope of primary prevention is limited. Since low birth weight has been shown to be associated with infantile cataracts, we examined risk factors for low birth weight, including maternal smoking, diabetes, and surrogates of maternal infection, and their relation to cataracts.
Methods::
We used data from the National Birth Defects Prevention Study, an ongoing multi-site, case-control study of major birth defects for birth years 2000-2003. Infants with a recognized chromosome abnormality or single gene disorder were excluded. For this analysis, infants with a first-degree relative with infantile cataracts (26 case- and 2 control-infants) were also excluded. Cases were infants diagnosed with cataracts by an ophthalmologist before age 1 year (N = 124) and controls were a random sample of live births (N = 3263). Associations were explored for all, bilateral (N = 35) and unilateral (N = 89) cases of infantile cataracts, adjusting for maternal age and race/ethnicity.
Results::
Very low birth weight (<1500g) was associated with both bilateral (adjusted odds ratio [OR] = 13.6; 95% Confidence Interval [CI] = 3.8-49.6) and unilateral (OR = 3.8; 95% CI = 1.1-13.1) cataracts, while low birth weight (1500-2499g) was only associated with bilateral cataracts (OR = 4.3; 95% CI = 1.7-10.8). Infants with unilateral cataracts were more likely to be born to primigravid women (OR = 1.7; 95% CI = 1.0-2.7) than women with two or more previous pregnancies. Women who had infants with bilateral cataracts were 2.6 times more likely to have used aspirin during pregnancy, although this result was not statistically significant (95% CI = 0.9-7.6). Infantile cataracts were not associated with maternal smoking, diabetes, reported maternal illness, fever, or use of antibiotics, antitussives, or other analgesics during pregnancy.
Conclusions::
Infants with cataracts are more likely to be of low birth weight or very low birth weight. Our findings suggest that bilateral and unilateral cataracts have different risk factors and should be examined separately.
Keywords: clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology • cataract • infant vision