Tuya C, Mutch W J, Broom I, McNeill G
Clinical Research Unit, NHS Grampian, Foresterhill, Aberdeen, UK.
J Thromb Haemost. 2005 Jun;3(6):1143-8. doi: 10.1111/j.1538-7836.2005.01431.x.
Several studies in singletons have found an association between low birth weight and increased plasma concentrations of clotting factors in adult life. Twins provide an opportunity to assess the possible contribution of genetic factors to this association. Forty-four monozygotic and 60 dizygotic same-sex twin pairs aged 19-50 years and 78 singleton controls matched for age, gestational age, gender, maternal age and parity were recruited from an obstetric database. Associations between both adult clottable fibrinogen (measured by the Clauss method) and intact fibrinogen (measured by the immunoprecipitation test), and birth weight were assessed by linear regression with adjustment for current age, gender, smoking and body mass index. Twins were significantly lighter at birth than singleton controls, but did not differ significantly in adult height, weight or fibrinogen levels from the singleton controls. There was a significant inverse association between birth weight and clottable fibrinogen levels among singleton controls [-0.22 g L(-1) kg(-1) (95% CI: -0.41,-0.03), P = 0.03], but not in unpaired twins. For intact fibrinogen there was no significant association with birth weight in either singleton controls or twins. In the within-pair analysis in twins there was a significant inverse association between differences in birth weight and clottable fibrinogen levels in dizygotic twin pairs [-0.34 g L(-1) kg(-1) (95% CI: -0.65,-0.02), P = 0.04], but not in monozygotic twin pairs [-0.12 g L(-1) kg(-1) (95% CI: -0.53, 0.28), P = 0.54]. These results support the possibility that genetic factors may contribute to the association between low birth weight and clottable fibrinogen levels.
多项针对单胎的研究发现，低出生体重与成年后血浆凝血因子浓度升高之间存在关联。双胞胎为评估遗传因素对这种关联可能产生的影响提供了契机。从一个产科数据库中招募了44对19至50岁的同卵同性双胞胎和60对异卵同性双胞胎，以及78名年龄、孕周、性别、母亲年龄和胎次相匹配的单胎对照者。通过线性回归分析评估成年可凝纤维蛋白原（采用克劳斯法测量）和完整纤维蛋白原（采用免疫沉淀试验测量）与出生体重之间的关联，并对当前年龄、性别、吸烟情况和体重指数进行校正。双胞胎出生时明显比单胎对照者体重轻，但在成年后的身高、体重或纤维蛋白原水平上与单胎对照者无显著差异。在单胎对照者中，出生体重与可凝纤维蛋白原水平之间存在显著的负相关[-0.22 g L(-1) kg(-1)（95%可信区间：-0.41，-0.03），P = 0.03]，但在未配对的双胞胎中不存在这种情况。对于完整纤维蛋白原，在单胎对照者或双胞胎中与出生体重均无显著关联。在双胞胎的配对分析中，异卵双胞胎对中出生体重差异与可凝纤维蛋白原水平之间存在显著的负相关[-0.34 g L(-1) kg(-1)（95%可信区间：-0.65，-0.02），P = 0.04]，但在同卵双胞胎对中不存在这种情况[-0.12 g L(-1) kg(-1)（95%可信区间：-0.53，0.28），P = 0.54]。这些结果支持了遗传因素可能导致低出生体重与可凝纤维蛋白原水平之间关联的可能性。
