孕前体重指数和孕期体重增长与新生儿体重的关系

目的探讨孕妇孕前体重指数（bodymassindex,BMI）和孕期体重增长与新生儿体重的关系。方法2006年7月1日至2007年6月30日,2734例于四川I大学华西第二医院住院分娩且病历资料完整孕妇,按孕前体重指数分组。体重指数〈16．75kg／m2,纳入低BMI组（n=51）,体重指数为（16．75～23．71）kg／m2纳入正常BMI组（n=2330）,体重指数〉23．71kg／m2,纳入高BMI组（n=353）。根据四川大学华西第二医院推荐的孕期适宜体重增长模式,将孕期体重增长分为三类：体重增长〈13．13kg,体重增长为（13．13～20．25）kg和体重增长≥20．25kg。将正常BMI组与高BMI组孕妇分别按体重增长进一步分为三个亚组,分析孕妇孕前体重指数和孕期体重增长与新生儿体重的关系。结果低BMI组、正常BMI组和高BMI组孕妇孕前体重指数与新生儿体重的相关系数（r）分别为0．128（P〉0．05）,0．138（P〈0．01）和0．126（P〈0．05）。低BMI组、正常BMI组和高BMI组孕妇孕期体重增加与新生儿体重的相关系数分别为0．629（P〈0．001）,0．236（P〈0．001）和0．195（P〈0．001）。正常BMI组孕妇孕期体重增加〈13．13kg亚组1与正常BMI组体重增加为（13．13～20．25）kg亚组1比较,巨大儿发生的OR=0．617,95％CI：0．424～0．864（P〈0．01）。正常BMI组孕妇孕期体重增加〉20．25kg亚组1与体重增加为（13．13～20．25）kg亚组1比较,巨大儿发生的OR=1．622,95％CI：1．116～2．356（P〈0．01）。正常BMI组中,各体重增长亚组比较,低体重儿发生率差异无显著意义（P〉0．05）。高BMI组中,各体重增长亚组比较,低体重儿、巨大儿发生率差异无显著意义（P〉0．05）。结论孕妇孕前体重指数及孕期体重增加与新生儿出生体重呈正相关。为降低巨大儿发生率,正常体重指数组孕期体重增加不宜超过20．25kg。     

Pre-pregnancy Body Mass Index, Gestational Weight Gain, and Other Maternal Characteristics in Relation to Infant Birth Weight

Objectives Infant birth weight is influenced by modifiable maternal pre-pregnancy behaviors and characteristics. We evaluated the relationship among pre-pregnancy body mass index (BMI), gestational weight gain, and infant birth weight, in a prospective cohort study. Methods Women were enrolled at ≤20 weeks gestation, completed in-person interviews and had their medical records reviewed after delivery. Infant birth weight was first analyzed as a continuous variable, and then grouped into Low birth weight (LBW) (<2,500 g), normal birth weight (2,500–3,999 g), and macrosomia (≥4,000 g) in categorical analysis. Pre-pregnancy BMI and gestational weight gain were categorized based on Institute of Medicine BMI groups and gestational weight gain guidelines. Associations among infant birth weight and pre-pregnancy BMI, gestational weight gain, and other factors were evaluated using multivariate regression. Risk ratios were estimated using generalized linear modeling procedures. Results Pre-pregnancy BMI was independently and positively associated with infant birth weight (β = 44.7, P = 0.001) after adjusting for confounders, in a quadratic model. Gestational weight gain was positively associated with infant birth weight (β = 19.5, P < 0.001). Lower infant birth weight was associated with preterm birth (β = −965.4, P < 0.001), nulliparity (β = −48.6, P = 0.015), and female babies (β = −168.7, P < 0.001). Less than median gestational weight gain was associated with twice the risk of LBW (RR = 2.04, 95% CI 1.34–3.11). Risk of macrosomia increased with increasing pre-pregnancy BMI and gestational weight gain (P for linear trend <0.001). Conclusions These findings support the need to balance pre-pregnancy weight and gestational weight gain against the risk of LBW and macrosomia among lean and obese women, respectively.     

Association of Body Mass Index and Body Mass Index Change with Mortality in Incident Peritoneal Dialysis Patients

Although high body mass index (BMI) appears to confer a survival advantage in hemodialysis patients, the association of BMI with mortality in continuous ambulatory peritoneal dialysis (CAPD) patients is uncertain. We enrolled incident CAPD patients and BMI was categorized according to World Health Organization classification for Asian population. BMI at baseline and one year after the initiation of peritoneal dialysis (PD) treatment was assessed to calculate the BMI change (∆BMI). Patients were split into four categories according quartiles of ∆BMI. Kaplan-Meier method and Cox regression proportional hazard analysis were performed to assess the association of BMI on outcomes. A total of 1263 CAPD patients were included, with a mean age of 47.8 ± 15.0 years, a mean BMI of 21.58 ± 3.13 kg/m². During a median follow-up of 25.3 months, obesity was associated with increased risk for cardiovascular diseases (CVD) death (adjusted hazard ratio (AHR) 2.01; 95% CI 1.14, 3.54), but not all-cause mortality. Additionally, patients with more BMI decline (>0.80%) during the first year after CAPD initiation had an elevated risk for both all-cause (AHR: 2.21, 95% CI 1.23–3.95) and CVD mortality (AHR 2.31, 95% CI 1.11, 4.84), which was independent of baseline BMI values.     

Self-reported Pre-pregnancy Weight Versus Weight Measured at First Prenatal Visit: Effects on Categorization of Pre-pregnancy Body Mass Index

To compare classification of pre-pregnancy body mass index (BMI) using self-reported pre-pregnancy weight versus weight measured at the first prenatal visit. Retrospective cohort of 307 women receiving prenatal care at the faculty and resident obstetric clinics at a Massachusetts tertiary-care center. Eligible women initiated prenatal care prior to 14 weeks gestation and delivered singleton infants between April 2007 and March 2008. On average, self-reported weight was 4 pounds lighter than measured weight at the first prenatal visit (SD 7.2 pounds; range: 19 pounds lighter to 35 pounds heavier). Using self-reported pre-pregnancy weight to calculate pre-pregnancy BMI, 4.2 % of women were underweight, 48.9 % were normal weight, 25.4 % were overweight, and 21.5 % were obese. Using weight measured at first prenatal visit, these were 3.6, 45.3, 26.4, and 24.8 %, respectively. Classification of pre-pregnancy BMI was concordant for 87 % of women (weighted kappa = 0.86; 95 % CI 0.81–0.90). Women gained an average of 32.1 pounds (SD 18.0 pounds) during pregnancy. Of the 13 % of the sample with discrepant BMI classification, 74 % gained within the same adherence category when comparing weight gain to Institute of Medicine recommendations. For the vast majority of women, self-reported pre-pregnancy weight and measured weight at first prenatal visit resulted in identical classification of pre-pregnancy BMI. In absence of measured pre-pregnancy weight, we recommend that providers calculate both values and discuss discrepancies with their pregnant patients, as significant weight loss or gain during the first trimester may indicate a need for additional oversight with potential intervention.     

母亲孕前体重指数和孕期增重对母婴预后的影响

目的探讨孕前体重指数(BMI)和孕期增重与新生儿出生体重及妊娠结局的关系,为降低高危妊娠和巨大儿发生率及难产发生率提供依据。方法以BMI为标准分为低体重组、正常体重组和肥胖组,分析孕妇体重过度增重、巨大儿发生率、难产发生率以及体重指数与新生儿体重、分娩方式和孕期并发症的关系。结果3组间新生儿出生体重有明显差异,巨大儿发生率分别为5.00%、6.10%和11.96%,有统计学意义(P0.05)。孕期体重增重过重与新生儿体重成正相关(P0.05);肥胖组妊娠期糖尿病发病率明显增多,是正常组的3倍,且妊高征发病率明显增高。3组分娩方式、难产(剖宫产和产钳助产)的发生率比较,有非常显著性差异。结论肥胖组的巨大儿、妊娠期糖尿病和妊高征的发生率都高于正常体重组和低体重组,孕前BMI和孕妇体重过度增长与新生儿出生体重和妊娠结局有关。     

Association of Body Mass Index with Ischemic and Hemorrhagic Stroke

Data on the association between body mass index (BMI) and stroke are scarce. We aimed to examine the association between BMI and incident stroke (ischemic or hemorrhagic) and to clarify the relationship between underweight, overweight, and obesity and stroke risk stratified by sex. We analyzed the JMDC Claims Database between January 2005 and April 2020 including 2,740,778 healthy individuals (Median (interquartile) age, 45 (38–53) years; 56.2% men; median (interquartile) BMI, 22.3 (20.2–24.8) kg/m²). None of the participants had a history of cardiovascular disease. Each participant was categorized as underweight (BMI <18.5 kg/m²), normal weight (BMI 18.5–24.9 kg/m²), overweight (BMI 25.0–29.9 kg/m²), or obese (BMI ≥ 30 kg/m²). We investigated the association of BMI with incidence stroke in men and women using the Cox regression model. We used restricted cubic spline (RCS) functions to identify the association of BMI as a continuous parameter with incident stroke. The incidence (95% confidence interval) of total stroke, ischemic stroke, and hemorrhagic stroke was 32.5 (32.0–32.9), 28.1 (27.6–28.5), and 5.5 (5.3–5.7) per 10,000 person-years in men, whereas 25.7 (25.1–26.2), 22.5 (22.0–23.0), and 4.0 (3.8–4.2) per 10,000 person-years in women, respectively. Multivariable Cox regression analysis showed that overweight and obesity were associated with a higher incidence of total and ischemic stroke in both men and women. Underweight, overweight, and obesity were associated with a higher hemorrhagic stroke incidence in men, but not in women. Restricted cubic spline showed that the risk of ischemic stroke increased in a BMI dose-dependent manner in both men and women, whereas there was a U-shaped relationship between BMI and the hemorrhagic stroke risk in men. In conclusion, overweight and obesity were associated with a greater incidence of stroke and ischemic stroke in both men and women. Furthermore, underweight, overweight, and obesity were associated with a higher hemorrhagic stroke risk in men. Our results would help in the risk stratification of future stroke based on BMI.     

Maternal Body Mass Index and Self-Reported Postpartum Depressive Symptoms

Objectives: The association between extremes of body mass index (BMI) and depression in women has been documented, yet little is known about the relationship between obesity and postpartum depression (PPD). This study seeks to characterize the association between BMI and PPD. Methods: The 2000–2001 Utah data from Pregnancy Risk Assessment Monitoring System (PRAMS) were used to determine the proportion of women, stratified by prepregnancy body mass index, reporting postpartum depressed mood and stressors during pregnancy. Results: The prevalence of self-reported moderate or greater depressive symptoms was 27.7% (S.E. ±2.2) in underweight, 22.8% (±1.2) in normal weight, 24.8% (±2.9) in overweight and 30.8% (±2.5) in obese women. After controlling for marital status and income, normal BMI (19.8–25.9) was associated with the lowest rate of self-reported postpartum depressive symptoms. There was a two-fold increase in self-reported depressive symptoms requiring assistance among overweight and obese women compared to normal weight women (1.53% normal, 2.99% overweight, and 3.10% obese [p < 0.001]). Obese women were significantly more likely to report emotional and traumatic stressors during pregnancy than normal weight women. Conclusion: This population-based survey suggests a potential association between prepregnancy body mass index and self-reported postpartum depressive symptoms. Prospective studies of association between obesity and PPD, with improved diagnostic precision are warranted.     

Maternal Religious Involvement and Breastfeeding Initiation and Duration

Although religious involvement is associated with a number of beneficial health outcomes, few studies have investigated whether religious involvement is associated with breastfeeding behaviors. Our analyses of 2 waves of data from the Fragile Families and Child Wellbeing Study (n = 4 166) indicate that mothers who frequently attend religious services are more likely to initiate breastfeeding than are mothers who never attend services. Understanding religious variations in breastfeeding may allow public health officials to more effectively target vulnerable populations.Researchers note important demographic and socioeconomic disparities in breastfeeding behaviors.1–4 Understanding variations in breastfeeding is critical given the numerous benefits that breast milk is shown to confer.5–8 Our study builds on recent interest in religion and health. Scholarship on maternal health suggests that church attendance is inversely associated with risky health behaviors among pregnant and postpartum women.9 Religious attendance, as well as specific religious subcultures, may influence breastfeeding behaviors.10,11 Investigating the link between religion and breastfeeding could bring to light potential public health interventions.We used data from 2 waves of the Fragile Families and Child Wellbeing Study (FFCWS) to analyze the association between religious involvement and breastfeeding initiation and duration. Ours is the first study to our knowledge to examine the association between religion and breastfeeding in a large, religiously and racially diverse sample of predominately unmarried mothers. Exploring religious variations in breastfeeding among this economically disadvantaged population is vital because breastfeeding rates remain low. Because religious institutions are well represented in the poorest neighborhoods, where there are few protective social institutions,12,13 understanding religious differences in breastfeeding may provide practitioners with opportunities to target programs in poorer communities.     

The Association between Television Viewing and Preschool Child Body Mass Index

This paper is a conceptual and methodological review of the literature on the impact of TV on preschoolers' weight status. A systematic search, of papers published between January 1995 and January 2010, identified twenty-six relevant studies. Fifteen of these were cross-sectional in design and eleven adopted a prospective design; a positive association between hours of TV and child adiposity was found in all but three studies. Although assessed in a limited number of studies, diet may mediate the relationship between TV viewing and BMI. Another likely mediator may be the content of TV programs watched; only three studies examined this association and findings were inconsistent. Our review revealed that research examining mediating effects is limited, focusing more on simple cross-sectional or prospective relationships between TV habits and child body mass index. Further investigation of the mechanisms by which TV viewing affects preschool weight gain is needed.     

Association of Perceived Neighborhood Safety on Body Mass Index

Objectives. We sought to determine whether there is an association between perceived neighborhood safety and body mass index (BMI), accounting for endogeneity.Methods. A random sample of 2255 adults from the Los Angeles Family and Neighborhood Survey 2000–2001 was analyzed using instrumental variables. The main outcome was BMI using self-reported height and weight, and the main independent variable was residents’ report of their neighborhood safety.Results. In adjusted analyses, individuals who perceived their neighborhoods as unsafe had a BMI that was 2.81 kg/m² (95% confidence interval [CI] = 0.11, 5.52) higher than did those who perceived their neighborhoods as safe.Conclusions. Our results suggest that clinical and public health interventions aimed at reducing rates of obesity may be enhanced by strategies to modify the physical and social environment that incorporate residents’ perceptions of their communities.Obesity is a major public health problem^1–5 that contributes to poor quality of life; increased incidence of diabetes, cardiovascular disease, and other chronic conditions; and higher mortality rates.⁵ During the last decade, population-based strategies to reduce obesity have emphasized modification of physical and social environments, which may be particularly important in disadvantaged communities. Low neighborhood socioeconomic status (SES),⁶ a higher proportion of Black and Latino residents,^7–10 barriers in the built environment (e.g., fewer places to walk),^11,12 lack of access to supermarkets or fresh fruits and vegetables,^6,13,14 and a higher density of fast food restaurants¹⁵ are all characteristics of residential environments associated with obesity. Research also suggests that low levels of collective efficacy (a perception of mutual trust and willingness to help each other)¹⁶ are associated with adolescent obesity. However, the mechanisms through which neighborhood social, economic, and physical characteristics lead to weight gain and obesity are not well characterized.Perceived neighborhood safety is a mechanism through which neighborhood characteristics may influence obesity. Residence in a neighborhood perceived as unsafe may contribute to obesity in a number of ways, including increased secretion of stress hormones,^17–19 lower rates of walking or other outdoor physical activity,^20–28 and higher rates of stress-related eating.^29–32 Perceived safety may reflect the physical, social, and resource characteristics of neighborhoods. For example, residents may perceive a neighborhood to be unsafe if supermarkets and retailers that sell fresh fruits and vegetables are unwilling to locate in their neighborhoods, or if fast food restaurants and stores that sell low-cost, calorie-dense foods tend to locate in their neighborhoods.^33–35 Yet, the limited literature on relations between perceived safety and body weight is mixed. One study found that mothers with young children, residing in large cities, and perceiving their neighborhoods as unsafe were more likely to be obese,³⁶ and another study found no association between perceived safety and obesity.³⁷ Similarly, in the larger body of literature on neighborhood safety and physical activity, some studies found an association of perceived neighborhood safety with physical activity levels,^20–26 although other analyses showed no such relationship,^38–42 suggesting a more complex etiology.We hypothesized that 1 reason for the inconsistent findings in these previous analyses—all of which were cross-sectional—is endogeneity bias, that is, the possibility that the findings from these studies may have been influenced by either reverse causality^36,43 or unmeasured neighborhood or individual characteristics influencing both perceived neighborhood safety and obesity. For example, reverse causality may occur if larger individuals, believing nobody would attack them because of their size, feel safer, or if larger individuals, being less agile and less physically fit and believing they cannot protect themselves, feel less safe. To address the possibility of endogeneity from reverse causality or unmeasured neighborhood or individual characteristics, we studied the association between perceived neighborhood safety and obesity in a population-based, geographically sampled cohort of residents in Los Angeles County, California. We used 2-stage least squares regression, a special case of an instrumental variables analysis that is a method developed to produce statistically consistent estimates when the covariate of interest is potentially endogenous. To our knowledge, no studies to date have used instrumental variables analysis to assess the relationship between neighborhood safety and obesity.     

Association between Nutrition Policies and Student Body Mass Index

In response to concerns about childhood obesity, many US states have implemented policies to limit the sale of unhealthy foods and beverages (e.g., snacks, desserts, and sugary drinks) sold in competition with school meal programs (i.e., competitive foods) in order to improve the nutritional environment of schools and support student health. This study measured state-level competitive food and beverage policies that require foods and beverages sold in à la carte lines, vending machines, and school stores to meet strong nutrition standards and tested the hypothesis that students living in states with stronger laws would have lower body mass index (BMI)-for-age percentiles. BMI data from a national sample of 1625 students attending 284 schools from the School Nutrition and Meal Cost Study were linked to state laws coded as part of the National Wellness Policy Study. A survey-adjusted linear regression model accounting for student and school-level characteristics showed that stronger state nutrition policies were associated with lower student BMI scores (coefficient: −0.06, 95% CI: −0.12, −0.00). Additional models indicated that stronger state policies were significantly associated with fewer unhealthy foods and beverages available in schools. These findings suggest that strong regulations on competitive foods and beverages may lead to improvements in the nutritional quality of the school environment and student BMI. Thus, current federal standards regulating snacks in US schools (i.e., Smart Snacks) are an important element of a comprehensive strategy to improve the school nutrition environment and reduce rates of childhood obesity.     

The Influence of Maternal Acculturation on Child Body Mass Index at Age 24 Months

Objective

Obesity rates in preschool-aged children are greatest among Latinos. Studies of the relationship of acculturation to obesity among Latino immigrants have primarily focused on adults and adolescents. We examined the influence of maternal acculturation on child body mass index (BMI) at age 24 and 36 months among predominantly Latino, low-income mother-child pairs enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children.

Design and methods

Maternal characteristics were obtained from interviewer-administered surveys conducted in English or Spanish at 6 to 20 weeks postpartum among 679 participants in a randomized controlled trial of a health promotion intervention in two urban areas in the Northeast. Acculturation measures included: nativity (born in the United States vs foreign born), parents' nativity, years of US residence (<8 years vs ≥8 years), and exclusive use of native language vs nonexclusive use (mixed or English only). Following repeated mailings and telephone calls requesting permission to obtain their child's height and weight from Special Supplemental Nutrition Program for Women, Infants, and Children records, informed consent was obtained from 108 mothers. Multivariable linear regression models of maternal acculturation and child BMI z score at age 24 months and age 36 months were estimated among all mother-child pairs and within immigrant-only mother-child pairs, adjusting for relevant maternal characteristics.

Results

At age 24 months, children of mothers with exclusive use of native language had higher BMI z scores compared to children of mothers with nonexclusive use among 91 mother-child pairs (β=.74, P=0.02) and within 63 immigrant-only mother-child pairs (β=.92, P=0.009).

Conclusions

Exclusive use of native language was associated with greater BMI in children as young as age 24 months. Future research should examine the mechanisms by which mothers' language acculturation may affect proximal determinants of energy balance in preschool children, including breastfeeding practices, dietary intake, and physical activity.     

The Association Between Body Mass Index in Adolescence and Obesity in Adulthood

PURPOSE: This study used data from the National Longitudinal Study of Youth 1979 to examine the association between body mass index (BMI) in adolescence and obesity in adulthood. METHODS: Measurements of height and weight from 1981 and 2002 were used to calculate BMI for a cohort of 1309 adolescents at baseline and during adulthood. Associations between BMI at age 16/17 and obesity (BMI > or =30) at age 37/38 were analyzed using logistic regression analysis. RESULTS: When the predicted probability of adult obesity equaled 0.5, the point on the adolescent BMI distribution was close to the 85th percentile for both sexes (83rd percentile for females and 86th percentile for males). Among adolescents with a BMI in the 85th-<95th percentile, 62% of the males and 73% of the females became obese adults. Among those with a BMI > or =95th percentile, 80% of the males and 92% of the females became obese adults. Versus those with a BMI <85th percentile, those with a BMI in the 85th-<95th percentile were more likely to be obese (odds ratio = 7 for males, 11 for females) as adults, and those with a BMI > or =95th percentile were most likely to be obese (odds ratio = 18 for males, 49 for females) as adults. CONCLUSION: Adolescents with a BMI > or =85th percentile are at elevated risk for obesity in adulthood. To prevent the development of obesity and its associated health risks, population-based efforts combined with targeted interventions for these high-risk adolescents are needed.     

体质指数与脑卒中发病率关系的研究进展

脑卒中在我国的许多城市和地区都已经成为第1和第2位死因及首位致残原因,而我国肥胖人群的不断增加,更加重了脑卒中的危害。因此,研究脑卒中发病的影响因素,探求肥胖对脑卒中发病的作用机制,是目前预防脑卒中发病的主要课题之一。对体质指数(BMI)与脑卒中及其亚型发病率的关系进行了综述,为开展积极有效的危险因素干预研究,降低脑卒中发病率提供科学依据。     

济南市7岁儿童BMI及体成分与血压水平的相关性分析

目的阐明儿童期BMI及体成分指数与血压水平的相关性,为成年期疾病的早期预防提供相关依据。方法对济南市910名7岁儿童进行身高、体重、血压和皮褶厚度测量,采用回归方程推算体脂比(BF%),计算脂肪组织指数(FMI)和非脂肪组织指数(FFMI)。结果 BMI,BF%,FMI,FFMI与收缩压和舒张压均呈一定程度正相关(P值均0.05),血压与FMI的相关性高于FFMI。高BMI、BF%百分位数组儿童的血压水平均显著高于低百分位数组(P值均0.05)。血压偏高的检出率为肥胖组超重组正常组消瘦组。结论儿童BMI及体成分指数与血压水平有显著的相关性。预防儿童高血压应从控制体脂肪、预防肥胖做起。     

The Profiling of Diet and Physical Activity in Reproductive Age Women and Their Association with Body Mass Index

Pre-pregnancy, pregnancy and postpartum are critical life stages associated with higher weight gain and obesity risk. Among these women, the sociodemographic groups at highest risk for suboptimal lifestyle behaviours and core lifestyle components associated with excess adiposity are unclear. This study sought to identify subgroups of women meeting diet/physical activity (PA) recommendations in relation to sociodemographics and assess diet/PA components associated with body mass index (BMI) across these life stages. Cross-sectional data (Australian National Nutrition and Physical Activity Survey 2011–2012) were analysed for pre-pregnancy, pregnant and postpartum women. The majority (63–95%) of women did not meet dietary or PA recommendations at all life stages. Core and discretionary food intake differed by sociodemographic factors. In pre-pregnant women, BMI was inversely associated with higher whole grain intake (β = −1.58, 95% CI −2.96, −0.21; p = 0.025) and energy from alcohol (β = −0.08, −0.14, −0.005; p = 0.035). In postpartum women, BMI was inversely associated with increased fibre (β = −0.06, 95% CI −0.11, −0.004; p = 0.034) and PA (β = −0.002, 95% CI −0.004, −0.001; p = 0.013). This highlights the need for targeting whole grains, fibre and PA to prevent obesity across life stages, addressing those most socioeconomically disadvantaged.