Mami Ishikuro

Blood Pressure Measured in the Clinic and at Home During Pregnancy Among Nulliparous and Multiparous Women: The BOSHI Study

BACKGROUND Hypertension during pregnancy can cause serious problems during delivery, such as stroke, premature delivery, or low birthweight. Nulliparity is believed to be a risk factor for hypertension during pregnancy. However, the relationship between parity and blood pressure determined at home during pregnancy is still unknown. METHODS We assessed the incidence of gestational hypertension or preeclampsia in 575 nulliparous and multiparous women. Also, we examined blood pressure measured in the clinic and at home among 530 normotensive pregnant women who received antenatal care at a maternity hospital in Japan. Clinic blood pressures (CBPs) were obtained by duplicate measurement at each antenatal care visit. The participants were also required to measure their own blood pressures every morning at home while they were pregnant. A linear mixed model was used for analysis of the blood pressure course throughout pregnancy. RESULTS A total of 315 nulliparous and 215 multiparous women were entered into this study (mean age, 30.1 ± 4.6 years and 33.0 ± 4.1 years, respectively). CBP levels during pregnancy among nulliparous women were significantly higher than among multiparous women (P = 0.02/P <0.0001 for systolic/diastolic blood pressure), whereas there were no significant differences in home blood pressure (HBP) levels during pregnancy between the two groups (P = 0.4/P = 0.2 for systolic/diastolic blood pressure). CONCLUSIONS HBP levels during pregnancy were shown not to differ between nulliparous and multiparous women, while CBP levels during pregnancy were higher among nulliparous than among multiparous women.

Daily Serial Hemodynamic Data During Pregnancy and Seasonal Variation: The BOSHI Study

Although there are some reports that low plasma volume or increased cardiac output is associated with developing preeclampsia, there are few reports of daily serial hemodynamic data during pregnancy. A total of 37 092 home blood pressure (BP) and heart rate (HR) measurements were obtained from 425 normal pregnant women. Heart rate and shock index (SI) gradually increased by gestational week 32 and then decreased, whereas double product (DP) increased linearly during pregnancy. Although systolic BP and DP were consistently and negatively correlated with daily minimum outside temperature, HR and SI were positively correlated with minimum outside temperature in summer.

Maternal clinic and home blood pressure measurements during pregnancy and infant birth weight: the BOSHI study

This prospective cohort study compared measurements of maternal home blood pressure (HBP) with clinic blood pressure (CBP) before 20 weeks’ gestation to determine associations with the risk of delivering a lower birth weight infant. A total of 605 Japanese women were included. Exposures were initial CBP, made between 10 weeks 0 days and 19 weeks 0 days, and HBP for comparison made within 1 week of CBP. Outcome was infant’s birth weight, categorized and ranked as follows: ⩾3500 g, 3000–3499 g, 2500–2999 g and <2500 g. The proportional odds model with possible confounding factors was applied to compare the associations between CBP and HBP on infant birth weight. When both CBP and HBP were included simultaneously, the adjusted odds ratios (ORs) per 1 standard deviation (1s.d.) increase in clinic and home diastolic BP (DBP) were 1.06 (95% confidence interval (CI): 0.87–1.30) and 1.28 (95% CI: 1.04–1.58), respectively. The adjusted ORs per 1s.d. increase in clinic and home mean arterial pressure (MAP) were 1.02 (95% CI: 0.83–1.24) and 1.29 (95% CI: 1.04–1.59), respectively. Systolic BP measurement was not associated with infant birth weight. In conclusion, high maternal home DBP and MAP before 20 weeks’ gestation was associated with a higher risk of lower infant birth weight than clinic DBP and MAP. Therefore, in addition to CBP, it may be worth having pregnant women measure HBP to determine the risk of lower infant birth weight.

Impact of the great east Japan earthquake on the body mass index of preschool children: a nationwide nursery school survey

Objective To evaluate the impact of the 2011 great east Japan earthquake on body mass index (BMI) of preschool children. Design Retrospective cohort study and ecological study. Setting Affected prefectures (Fukushima, Miyagi and Iwate) and unaffected prefectures in northeast Japan. Participants The cohort study assessed 2033 and 1707 boys and 1909 and 1658 girls in 3 affected prefectures and unaffected prefectures, respectively, all aged 3–4 years at the time of the earthquake. The ecological study examined random samples of schoolchildren from the affected prefectures. Primary and secondary outcome measures The cohort study compared postdisaster changes in BMIs and the prevalence of overweight and obese children. The ecological study evaluated postdisaster changes in the prevalence of overweight children. Results 1 month after the earthquake, significantly increased BMIs were observed among girls (+0.087 kg/m2 vs unaffected prefectures) in Fukushima and among boys and girls (+0.165 and +0.124 kg/m2, respectively vs unaffected prefectures) in Iwate. 19 months after the earthquake, significantly increased BMIs were detected among boys and girls (+0.137 and +0.200 kg/m2, respectively vs unaffected prefectures) in Fukushima, whereas significantly decreased BMIs were observed among boys and girls (−0.218 and −0.082 kg/m2, respectively vs unaffected prefectures) in Miyagi. 1 month after the earthquake, Fukushima, Miyagi and Iwate had a slightly increased prevalence of overweight boys, whereas Fukushima had a slightly decreased prevalence of overweight girls, compared with the unaffected prefectures. The ecological study detected increases in the prevalence of overweight boys and girls in Fukushima who were 6–11 and 6–10 years of age, respectively. Conclusions These results suggest that in the affected prefectures, preschool children gained weight immediately after the earthquake. The long-term impact of the earthquake on early childhood growth was more variable among the affected prefectures, possibly as a result of different speeds of recovery.

Eczema and Asthma Symptoms among Schoolchildren in Coastal and Inland Areas after the 2011 Great East Japan Earthquake: The ToMMo Child Health Study.

After the Great East Japan Earthquake of 2011, there has been a concern about health problems among children. Therefore, we investigated the prevalence of wheeze and eczema symptoms and associated factors among children in areas primarily affected by the disaster. From 2012 to 2014, we distributed the parent-administered questionnaire to 25,198 children in all 233 public schools in the 13 municipalities of Miyagi Prefecture in northeast Japan. A total of 7,155 responses (mean age 10.5 ± 2.2 years) were received (response rate: 28.4%). The prevalence of allergic symptoms according to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire in 2nd, 4th, 6th, and 8th graders was 12.4%, 9.9%, 9.3%, and 5.6% for wheeze, and 20.1%, 18.0%, 14.0%, and 12.4% for eczema. In multivariate logistic analysis, younger age, history of hospitalization, and difficulties in childrens daily lives as assessed by the Strengths and Difficulties Questionnaire (SDQ), were significantly and consistently associated with both allergic symptoms (both P < 0.05). Living in a coastal municipality was also associated with eczema symptoms (P = 0.0278). The prevalence of eczema symptoms in the 2nd (20.1%) and 8th (12.4%) grades was significantly higher than previously reported in Japan. Living in a coastal municipality was independently associated with eczema symptoms, and psychometric properties were also closely linked to allergic symptoms. These findings are clinically important for understanding the risks of allergic disorders after natural disasters.

Parity as a factor affecting the white-coat effect in pregnant women: the BOSHI study.

Parity has previously been reported to affect the difference in blood pressure (BP) measured in the office and at home, also known as the white-coat effect, during pregnancy. The objective of this study was to identify possible factors that cause the white-coat effect during pregnancy, focusing on parity. In total, 530 pregnant women (31.3±4.7 years old) who delivered at a maternal clinic were eligible for the study. The association between parity and the white-coat effect (clinic BP compared with home BP) was investigated for each trimester of pregnancy by multivariate analysis of covariance adjusted for age, body mass index, family history of hypertension and smoking habits. The magnitudes of the white-coat effect for systolic BP in the first, second and third trimesters were 4.1±9.8, 3.4±7.1 and 1.8±6.0 mm Hg, respectively and those for diastolic BP were 3.8±7.4, 1.6±5.8 and 2.4±4.9 mm Hg, respectively. Parity was significantly and negatively associated with the white-coat effect for systolic BP in the first trimester of pregnancy (nulliparous women: 5.07±0.61 mm Hg and multiparous women: 2.78±0.74 mm Hg, P=0.02) as well as for diastolic BP in the second and third trimesters of pregnancy. Age, body mass index, family history of hypertension and smoking were not significantly associated with the white-coat effect in any trimester of pregnancy. Parity may have an influence on the white-coat effect in pregnancy; however, the observed effect, on average 1–2 mm Hg, was small.

Blood pressure changes during pregnancy

We read, with great interest, the article by Jwa et al. analyzing whether a shift in blood pressure (BP) class, as defined by the Japanese Society of Hypertension Guidelines for the management of hypertension 2009 (JSH 2009), predicts pregnancy-induced hypertension (PIH) among pregnant women in Japan.1 The study showed that there was less risk of PIH occurring among pregnant women with low BP at 20 weeks of pregnancy even when these women were found to have high BP at 16 weeks. This interesting finding might indicate that a decreasing BP in the second trimester (mid-pregnancy fall) has an impact on the occurrence of PIH. We have previously shown that BP measured at home (home BP) falls from the first trimester to the second trimester and then increases up until the time of delivery.2 The mid-pregnancy fall in healthy pregnant women might be caused by a decrease in total peripheral vascular resistance owing to vasodilatation in early pregnancy.3 The lack of a mid-pregnancy fall among women with pre-eclampsia has suggested a failure of normal cardiovascular adaptation to pregnancy as a result of endothelial dysfunction.4 Therefore, we speculate that the mid-pregnancy fall has certain clinical implications. By contrast, Silva et al. reported that there was no midpregnancy fall in BP.5 Their study was a part of the Generation R Study conducted from 2002 to 2006, a population-based prospective cohort study of subjects from fetal life until young adulthood, with 9778 mothers of various ethnicities and their children in the Netherlands. In the Generation R Study, a mid-pregnancy fall in systolic BP was not found, and the authors discussed the absence of a mid-pregnancy fall in diastolic BP only for women with a low educational level. Thus, whether a mid-pregnancy fall occurs is still uncertain, and further studies must be done to obtain more definitive evidence. Therefore, we are very interested in BP changes during pregnancy among pregnant women with or without hypertensive disorders and among all participants in the study conducted by Jwa et al. We have also shown that a seasonal trend occurs in BP changes during pregnancy and that the mid-pregnancy fall using home BP measurement is affected by the expected dates of confinement.6 In our study, pregnant women who delivered in winter tended to have higher BPs than those who delivered in summer. This finding indicates that the lowest daily temperature affects the BP changes during pregnancy and may contribute to the occurrence of PIH. We are also curious to understand how seasonal effects contribute to predicting PIH by a shift in BP class in the study by Jwa et al. It might be difficult to identify small changes, such as a mid-pregnancy fall or seasonal variation, when using clinic BP, because clinic BP has a greater variation than home BP. Macdonald-Wallis et al. showed a clinic BP change during pregnancy in around 10 000 normotensive pregnant women in the UK who joined the Avon Longitudinal Study of Parents and Children.7 It seems that clinic BPs of normotensive pregnant women had a mid-pregnancy fall, as observed in our study. Because, in Japan, pregnant women generally visit antenatal care clinics or hospitals once every 4 weeks until week 23, once every 2 weeks from weeks 24–35, and once a week after week 36, Jwa et al. might be able to evaluate clinic BP changes during pregnancy in more detail than have previous studies.5,7 A detailed evaluation of clinic BP would be helpful for gaining a better understanding of the mechanism of BP changes during pregnancy and for predicting the risk of hypertension during pregnancy. Therefore, we would like to ask Jwa et al. to provide the clinic BP values at each antenatal care visit throughout pregnancy.

Prevalence and determinants of inadequate use of folic acid supplementation in Japanese pregnant women: the Japan Environment and Children’s Study (JECS)

Abstract Objective: The aim of the study was to clarify the prevalence and determinants of inadequate use of folic acid supplementation in pregnant Japanese women. Methods: This study was part of the Japan Environment and Children’s Study, a nationwide and government-funded birth cohort study. We collected information on the use of folic acid supplementation before and during pregnancy and characteristics of participants using self-administered questionnaire. Results: Among 9849 women who completed the data collection for this study, the prevalence of inadequate users was 92.6% of the total population and varied from 84.5% to 96.2% among regions. On the basis of multivariate logistic regression analysis, younger age, not married, lower family income, multipara, natural conception and no history of spontaneous abortion were found to be determinants for inadequate users of folic acid supplementation. Conclusion: Most Japanese pregnant women show inadequate folic acid supplementation use. Japanese women of child-bearing age need to be specifically informed about the need for periconceptional intake of folic acid to prevent neural tube defects.

Associations Between Visit-to-visit Variability in Blood Pressure Measured in the Office and Antihypertensive Drugs: The J-HOME-Morning Study

The factors associated with visit-to-visit variability in blood pressure (BP) measured in the office between the two visits were identified in 1379 treated hypertensive patients (mean age, 66.1 ± 11.0 y; women, 53.8%). Multivariate regression analysis showed that office BP and visit-to-visit heart rate variability were positively associated with visit-to-visit BP variability, whereas body mass index, duration of antihypertensive medication, and taking amlodipine were negatively associated with visit-to-visit BP variability. Further prospective studies are required to clarify the causal relationships between these factors and visit-to-visit BP variability among treated hypertensive patients.

Drug Use before and during Pregnancy in Japan: The Japan Environment and Children’s Study

Purpose: To elucidate drug use before and during pregnancy in Japan. Methods: The Japan Environment and Children’s Study (JECS) is an ongoing nationwide birth cohort study. We analyzed data from JECS involving cases where drugs were used for 12 months before pregnancy was diagnosed, between the time of diagnosis of pregnancy until week 12 of pregnancy, and after week 12 of pregnancy. Results: We analyzed data from 97,464 pregnant women. The percentages of pregnant women who had taken one or more drugs and supplements before diagnosis of pregnancy, between the time of diagnosis of pregnancy until week 12 of pregnancy, and after week 12 of pregnancy, were 78.4%, 57.1%, and 68.8% respectively. Excluding iron supplements, folic acid, and other vitamins and minerals, the percentages of women taking supplements were 75.3%, 36.0%, and 51.7% at each respective time point. The following drugs and supplements were frequently used for 12 months before pregnancy diagnosis: Commercially available antipyretics, analgesics, and/or medicine for treating common cold (34.7%), antipyretics, analgesics, and/or medicine for treating common colds, which were prescribed in hospitals (29.8%), antimicrobial drugs (14.0%), and anti-allergy drugs (12.5%). The following drugs and supplements were frequently used from the time of pregnancy diagnosis until week 12 of pregnancy, and after week 12 of pregnancy: folic acid (28.9% and 26.2%), antipyretics, analgesics and/or medicines for treating common cold, that were prescribed in hospitals (7.8% and 13.3%), Chinese herbal medicines (6.0% and 9.4%, and uterine relaxants (5.1% and 15.2%). Conclusions: The analysis of a nationwide cohort study showed that a high percentage of Japanese pregnant women were taking medicinal drugs. Further research is required to elucidate the relationship between drug use during pregnancy and birth defects in Japan.