The purpose of this study was to investigate whether pregnancy calcium supplementation affects offspring blood pressure and growth in The Gambia where calcium intakes are low (300-400 mg/d).
Follow-up of offspring born during a randomized controlled trial of pregnancy calcium supplementation (ISRCTN96502494, 1996-2000) in which mothers were randomly assigned to 1500 mg Ca/d (Ca) or placebo (P) from 20 wk pregnancy to delivery. Offspring were enrolled at age 3 y in studies where blood pressure and anthropometry were measured under standardized conditions at approximately 2-yearly intervals. Mean blood pressure and growth curves were fitted for females and males separately, using the longitudinal SuperImposition by Translation and Rotation (SITAR) mixed effects model. This generates 3 individual-specific random effects: size, timing, and intensity, reflecting differences in size, age at peak velocity, and peak velocity through puberty relative to the mean curve, respectively.
Five hundred twenty-three singleton infants were born during the trial (maternal group assignment: Ca/P = 259/264). Four hundred ninety-one were enrolled as children (females: F-Ca/F-P = 122/129 and males: M-Ca/M-P = 119/121) and measured regularly from 3.0 y to mean age 18.4 y; 90% were measured on ≥8 occasions. SITAR revealed differences in the systolic blood pressure and height curves between pregnancy supplement groups in females, but not in males. F-Ca had lower systolic blood pressure than F-P at all ages (size = -2.1 ± SE 0.8 mmHg; P = 0.005) and lower peak height velocity (intensity = -2.9 ± SE 1.1%, P = 0.009). No significant pregnancy supplement effects were seen for other measures.
This study showed, in female offspring, that pregnancy calcium supplementation may lower systolic blood pressure and slow linear growth in childhood and adolescence, adding to evidence of offspring sexual dimorphism in responses to maternal supplementation. Further research is warranted on the long-term and intergenerational effects of antenatal supplementations. This trial was registered at ISRCTN Registry as ISRCTN96502494.
目的:本研究的目的是调查在钙摄入量较低(300-400mg/d)的冈比亚,孕期补钙是否会影响后代的血压和生长。
方法:在一项怀孕补钙的随机对照试验(ISRCTN96502494,1996-2000)中对出生的后代进行随访,其中母亲从怀孕20周到分娩被随机分配到1500mgCa/d(Ca)或安慰剂(P)。后代在3岁时被纳入研究,其中血压和人体测量学在标准化条件下以大约2年的间隔进行测量。分别拟合女性和男性的平均血压和生长曲线,使用纵向叠加平移和旋转(SITAR)混合效应模型。这产生了3个个体特定的随机效应:大小,定时,和强度,反映大小的差异,峰值速度年龄,和相对于平均曲线的青春期峰值速度,分别。
结果:试验期间出生了23名单胎婴儿(母体组分配:Ca/P=259/264)。招募了四百九十一名儿童(女性:F-Ca/F-P=122/129,男性:M-Ca/M-P=119/121),并定期从3.0岁到平均年龄18.4岁进行测量;在≥8次的情况下测量了90%。SITAR揭示了女性妊娠补充剂组之间收缩压和身高曲线的差异,但不是男性。在所有年龄段,F-Ca的收缩压均低于F-P(大小=-2.1±SE0.8mmHg;P=0.005),峰高速度较低(强度=-2.9±SE1.1%,P=0.009)。其他措施未发现明显的妊娠补充效果。
结论:这项研究表明,在雌性后代中,孕期补钙可以降低收缩压和减缓儿童期和青春期的线性生长,增加了后代对母亲补充的性二态性的证据。需要进一步研究产前补充的长期和代际影响。该试验在ISRCTN注册中心注册为ISRCTN96502494。