
Does normal variation in birthweight confer susceptibility to health problems? A co-twin control study
Author(s) -
Jennifer R. Harris m.fl
Publication year - 2009
Publication title -
norsk epidemiologi
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.134
H-Index - 19
eISSN - 1891-5477
pISSN - 0803-2491
DOI - 10.5324/nje.v7i1.353
Subject(s) - twin study , medicine , variation (astronomy) , demography , birth weight , pregnancy , pediatrics , biology , heritability , genetics , physics , sociology , astrophysics
ABSTRACTPopulation-based twin data were used to study whether normal variation in birthweight confersdisadvantage for a variety of health outcomes from birth through young adulthood. The sample consists of5,864 identical and fraternal twins and includes 2,570 intact pairs. Variation in birthweight may beassociated with an increased risk for epilepsy in males and with refractive disorders, chronic ear infectionsand intestinal problems in women. Two variants of the co-twin control design, based on identical twinsonly, were used to control for genetic and shared environmental effects that influence both birthweight andthe health outcome. Results indicated that the prevalence of health outcomes was not greater among thelighter twin from birthweight discordant pairs. Furthermore, intra-pair differences in birthweight betweenmembers of pairs who were health-discordant were significant only for nearsightedness among the MZmales. Due to lack of statistical power these results should be interpreted with caution.