孕期吸烟与高血压之间令人费解的关联。

The puzzling association between smoking and hypertension during pregnancy.

作者信息

Zhang J, Klebanoff M A, Levine R J, Puri M, Moyer P

机构信息

Division of Epidemiology, Statistics and Prevention Research, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.

出版信息

Am J Obstet Gynecol. 1999 Dec;181(6):1407-13. doi: 10.1016/s0002-9378(99)70384-4.

DOI:10.1016/s0002-9378(99)70384-4

PMID:10601921

Abstract

OBJECTIVE

The object of this study was to examine the association between maternal smoking and hypertension during pregnancy.

STUDY DESIGN

We used data from the Collaborative Perinatal Project, a large prospective cohort study that collected detailed information on blood pressure, proteinuria, smoking, and placental morphologic and histologic characteristics. A total of 9651 healthy primigravid women without chronic hypertension who had been enrolled in the study at the first or second trimester (average 18 weeks' gestation) and had had >/=3 prenatal visits were included. Gestational hypertension was defined as diastolic blood pressure >/=90 mm Hg on 2 occasions from 24 weeks' gestation to 2 weeks post partum. Preeclampsia was defined as gestational hypertension plus >/=2 urine samples containing >/=1+ protein according to dipstick measurement during the same gestational period.

RESULTS

After we controlled for prepregnancy body mass, age, socioeconomic status, and race, both past smoking and smoking during pregnancy were associated in a dose-response pattern with reduced risks of gestational hypertension and preeclampsia. For women who smoked >/=10 cigarettes/d the relative risks with respect to women who had never smoked were 0.6 (95% confidence interval, 0.4-0.9) for gestational hypertension and 0.5 (95% confidence interval, 0.4-0.7) for preeclampsia. This protective effect was observed both for mild and severe gestational hypertension and for preeclampsia. The more and the longer a woman had smoked previously, the lower was her risk of development of hypertension during pregnancy. This association could not be explained by confounding factors, by changes in placental morphologic or histopathologic characteristics, by maternal net weight gain, or by elevated liver enzyme bioactivity.

CONCLUSION

Smoking is associated with a reduced risk of hypertension during pregnancy. The protective effect appears to continue even after cessation of smoking. Further basic research on this issue is warranted.

摘要

目的

本研究旨在探讨孕期母亲吸烟与高血压之间的关联。

研究设计

我们使用了围产期协作项目的数据，这是一项大型前瞻性队列研究，收集了有关血压、蛋白尿、吸烟以及胎盘形态学和组织学特征的详细信息。总共纳入了9651名健康初产妇，她们在孕早期或孕中期（平均妊娠18周）入组本研究，且产前检查次数≥3次，均无慢性高血压。妊娠期高血压定义为妊娠24周后至产后2周内，两次测量舒张压≥90 mmHg。子痫前期定义为妊娠期高血压加上同期尿试纸测量显示≥2份尿样含≥1+蛋白。

结果

在我们对孕前体重、年龄、社会经济状况和种族进行控制后，既往吸烟和孕期吸烟均呈剂量反应模式与妊娠期高血压和子痫前期风险降低相关。对于每天吸烟≥10支的女性，与从不吸烟的女性相比，妊娠期高血压的相对风险为0.6（95%置信区间，0.4 - 0.9），子痫前期的相对风险为0.5（95%置信区间，0.4 - 0.7）。在轻度和重度妊娠期高血压以及子痫前期中均观察到这种保护作用。女性既往吸烟量越多、时间越长，其孕期患高血压的风险就越低。这种关联无法用混杂因素、胎盘形态学或组织病理学特征的变化、母亲净体重增加或肝酶生物活性升高来解释。