Iino Kaori, Higuchi Tsuyoshi, Tanaka Kanji, Nakaji Shigeyuki, Yokoyama Yoshihito, Mizunuma Hideki
Department of Obstetrics and Gynecology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Division of Health Sciences, Department of Disability and Health, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
JMA J. 2023 Jan 16;6(1):48-54. doi: 10.31662/jmaj.2022-0102. Epub 2022 Nov 30.
Women who experience maternal complications, including pre-eclampsia, have a higher risk of cardiovascular disease development. Although the mechanism remains unclear, there is a hypothesis that pregnancy would be a stress test for cardiovascular disease. This study aimed to investigate whether changes in blood pressure during pregnancy would be associated with developing hypertension, which is a main risk of cardiovascular disease.
We conducted a retrospective study by collecting Maternity Health Record Books from 735 middle-aged women. Of these, 520 women were selected based on our criteria. 138 were defined as the hypertensive group according to the criteria of receiving antihypertensive medications or blood pressures of >140/90 mmHg at the survey. The rest 382 were defined as the normotensive group. We compared the blood pressures of the hypertensive group with those of the normotensive group during pregnancy and postpartum. Then, 520 women were divided into quartiles (Q1-Q4) according to their blood pressures during pregnancy. After the changes in blood pressure for each gestational month relative to nonpregnant measurements were calculated, the changes in blood pressure were compared among the four groups. Additionally, the rate of developing hypertension was evaluated among the four groups.
The average age of the participants was 54.8 years (range: 40-85 years) at the time of the study and 25.9 years (range: 18-44 years) at delivery. There were significant differences in blood pressure during pregnancy between the hypertensive group and the normotensive group. Meanwhile, these two groups did not indicate any differences in blood pressure in postpartum. Higher mean blood pressure during pregnancy was associated with smaller changes in blood pressure during pregnancy. The rate of development of hypertension in each group of systolic blood pressure was 15.9% (Q1), 24.6% (Q2), 29.7% (Q3), and 29.7% (Q4). The rate of development of hypertension in each group of diastolic blood pressure (DBP) was 18.8% (Q1), 24.6% (Q2), 22.5% (Q3), and 34.1% (Q4).
Changes in blood pressure during pregnancy are small in women who have a higher risk of hypertension. Levels of blood pressure during pregnancy may be reflected in individual stiffness of blood vessels by the burden of pregnancy. If so, levels of blood pressure would be used to facilitate highly cost-effective screening and interventions for women with a high risk of cardiovascular diseases.
经历过包括先兆子痫在内的孕产妇并发症的女性，患心血管疾病的风险更高。尽管其机制尚不清楚，但有一种假说认为，怀孕可能是对心血管疾病的一种压力测试。本研究旨在调查孕期血压变化是否与高血压的发生有关，而高血压是心血管疾病的主要风险因素。
我们通过收集735名中年女性的孕产妇健康记录册进行了一项回顾性研究。其中，根据我们的标准选择了520名女性。根据接受降压药物治疗的标准或调查时血压>140/90 mmHg，将138名女性定义为高血压组。其余382名女性定义为血压正常组。我们比较了高血压组和血压正常组在孕期和产后的血压。然后，根据孕期血压将520名女性分为四分位数（Q1-Q4）。在计算每个孕周相对于非孕期测量值的血压变化后，比较了四组之间的血压变化。此外，还评估了四组中高血压的发生率。
研究时参与者的平均年龄为54.8岁（范围：40-85岁），分娩时为25.9岁（范围：18-44岁）。高血压组和血压正常组在孕期的血压存在显著差异。同时，这两组在产后血压方面没有显示出任何差异。孕期平均血压较高与孕期血压变化较小有关。收缩压每组的高血压发生率分别为15.9%（Q1）、24.6%（Q2）、29.7%（Q3）和29.7%（Q4）。舒张压（DBP）每组的高血压发生率分别为18.8%（Q1）、24.6%（Q2）、22.5%（Q3）和34.1%（Q4）。
高血压风险较高的女性孕期血压变化较小。孕期血压水平可能通过怀孕负担反映个体血管硬度。如果是这样，血压水平将有助于对心血管疾病高危女性进行高成本效益的筛查和干预。
