Jen Jen Chang

Measuring the Environment for Friendliness Toward Physical Activity: A Comparison of the Reliability of 3 Questionnaires

OBJECTIVES We tested the reliability of 3 instruments that assessed social and physical environments. METHODS We conducted a test-retest study among US adults (n = 289). We used telephone survey methods to measure suitableness of the perceived (vs objective) environment for recreational physical activity and nonmotorized transportation. RESULTS Most questions in our surveys that attempted to measure specific characteristics of the built environment showed moderate to high reliability. Questions about the social environment showed lower reliability than those that assessed the physical environment. Certain blocks of questions appeared to be selectively more reliable for urban or rural respondents. CONCLUSIONS Despite differences in content and in response formats, all 3 surveys showed evidence of reliability, and most items are now ready for use in research and in public health surveillance.

Sleep deprivation during pregnancy and maternal and fetal outcomes: Is there a relationship?

Sleep duration in the population has been declining. Women occupy an increasingly prominent place in the work force without reducing most of their responsibilities at home. Consequently, sleep needs are often pushed to the bottom of womens daily priority list. Prior research has indicated that sleep deprivation is associated with higher levels of pro-inflammatory serum cytokines. This is important because higher plasma concentrations of pro-inflammatory serum cytokine levels are associated with postpartum depression and adverse birth outcomes such as preterm delivery. However, little research has directly examined how sleep deprivation may affect maternal and fetal outcomes. This review summarizes the existing data on the effect of sleep deprivation during pregnancy on maternal and fetal outcomes. We review supporting evidence for the hypotheses that sleep deprivation during pregnancy increases the risk of preterm delivery and postpartum depression, and that systemic inflammation is the causal mechanism in the association. Prior research on sleep in pregnancy has been limited by varying data collection methods, subjective self-reported sleep measures, small and non-representative samples, cross-sectional designs; descriptive or non-hypothesis driven studies. Future research with longitudinal study designs is needed to allow examination of the effect of sleep deprivation on adverse maternal and fetal outcomes.

The role of repeat victimization in adolescent delinquent behaviors and recidivism

PURPOSE To report prevalence of adolescent victimization and delinquency recidivism as well as to assess the association between repeat victimization and delinquency recidivism in a large, population-based sample of high school seniors. METHODS A nationally representative sample of the Monitoring the Future Project (about 17,000 high school seniors from 1996 to 1999) was analyzed as a pooled sample. The analysis was based on self-reported measures of ten different types of delinquent behaviors including violent and property offenses. Other measures included in the analysis are victimization and information about sociodemographic (e.g,. geographic region, parental education, number of parents in the home) and lifestyle (e.g., grade from average, truancy, work experience, religious commitment) characteristics. Pairwise and multivariate methods were used to examine the risk association between repeat victimization and delinquency recidivism. RESULTS From 1996 to 1999, a downward trend was observed for most types of delinquent behaviors: recidivism among seniors except for hitting instructors/supervisors, damaging school property, and car theft. For the same study period, the prevalence of victimization recidivism was also on the decline except for injury with a weapon and physical threats. Repeat victimization was found to be significantly associated with delinquency recidivism. Other risk factors more frequently associated with delinquency recidivism included gender, race, drug use, poor school performance, truancy, risk-seeking, and conflicts with parents. CONCLUSIONS The present study showed a significant association between repeat victimization and delinquent recidivism; it identified characteristics of adolescent at risk of repetitive delinquent behaviors, which could be used for planning intervention strategies.

Recurrent preeclampsia: the effect of weight change between pregnancies.

OBJECTIVE: To estimate whether the risk of recurrent preeclampsia is affected by interpregnancy change in body mass index (BMI). METHODS: We conducted a population-based cohort study using Missouri maternally linked birth certificates for 17,773 women whose first pregnancies were complicated by preeclampsia. The women were placed into three groups: those who decreased their BMIs, those who maintained their BMIs, and those who increased their BMIs between their first two pregnancies. The primary outcome was recurrent preeclampsia in the second pregnancy. Adjusted risk ratios and 95% confidence intervals were calculated using Poisson regression analysis. RESULTS: The overall rate of recurrent preeclampsia in women who decreased their BMIs between pregnancies was 12.8% (risk ratio 0.70, confidence interval 0.60–0.81) compared with 14.8% if BMI was maintained and 18.5% in those who increased their BMIs (risk ratio 1.29, confidence interval 1.20–1.38). Within the normal weight, overweight, and obese weight categories, women who decreased BMI between pregnancies were less likely to experience recurrent preeclampsia. Women in all weight categories who increased their BMIs between pregnancies were more likely to experience recurrent preeclampsia. CONCLUSION: Interpregnancy weight reduction decreases the risk of recurrent preeclampsia and should be encouraged in women who experience preeclampsia. LEVEL OF EVIDENCE: II

The Association of Sleep Duration and Depressive Symptoms in Rural Communities of Missouri, Tennessee, and Arkansas

PURPOSE To determine the association between sleep duration and depressive symptoms in a rural setting. METHODS We conducted a cross-sectional study using data from Wave 3 of the Walk the Ozarks to Wellness Project including 12 rural communities in Missouri, Arkansas, and Tennessee (N = 1,204). Sleep duration was defined based on average weeknight and weekend hours per day: short (<7), optimal (7-8), and long (>8). The primary outcome was self-reported elevated depressive symptoms. Multivariable logistic regression was used to estimate adjusted prevalence odds ratios (aPOR) and 95% confidence intervals (95% CI). FINDINGS Elevated depressive symptoms were common in this rural population (17%). Depressive symptoms were more prevalent among subjects with short (26.1%) and long (24%) sleep duration compared to those with optimal (11.8%) sleep duration. After adjusting for age, gender, race, education, employment status, income, and BMI, short sleep duration was associated with increased odds of elevated depressive symptoms (aPOR = 2.12, 95% CI: 1.49, 3.01), compared to optimal sleep duration. Conversely, the association between long sleep duration and depressive symptoms was not statistically significant after covariate adjustment. Similar findings were observed when we excluded individuals with insomnia symptoms for analysis. CONCLUSIONS This study suggests that short sleep duration (<7 hours per night) and depressive symptoms are common among rural populations. Short sleep duration is positively associated with elevated depressive symptoms. The economic and health care burden of depression may be more overwhelming among rural populations, necessitating the need to target modifiable behaviors such as sleep habits to improve mental health.

Birth outcomes of planned home births in Missouri: a population-based study.

We evaluated the birth outcomes of planned home births. We conducted a retrospective cohort study using Missouri vital records from 1989 to 2005 to compare the risk of newborn seizure and intrapartum fetal death in planned home births attended by physicians/certified nurse midwives (CNMs) or non-CNMs with hospitals/birthing center births. The study sample included singleton pregnancies between 36 and 44 weeks of gestation without major congenital anomalies or breech presentation ( N = 859,873). The adjusted odds ratio (aOR) of newborn seizures in planned home births attended by non-CNMs was 5.11 (95% confidence interval [CI]: 2.52, 10.37) compared with deliveries by physicians/CNMs in hospitals/birthing centers. For intrapartum fetal death, aORs were 11.24 (95% CI: 1.43, 88.29), and 20.33 (95% CI: 4.98, 83.07) in planned home births attended by non-CNMs and by physicians/CNMs, respectively, compared with births in hospitals/birthing centers. Planned home births are associated with increased likelihood of adverse birth outcomes.

Prepregnancy body mass index in a first uncomplicated pregnancy and outcomes of a second pregnancy

OBJECTIVE This study examined the effect of body mass index (BMI) before a first uncomplicated pregnancy on maternal and fetal outcomes in a subsequent pregnancy, including preterm births, preeclampsia, cesarean delivery, small for gestational age, large for gestational age, and neonatal deaths. STUDY DESIGN We conducted a population-based cohort study (n = 121,092) using the Missouri maternally linked birth registry (1989 through 2005). Multivariable binary logistic regression models were fit to estimate odds ratios and 95% confidence intervals for the parameters of interest after controlling for sociodemographic and pregnancy-related confounders in the second pregnancy. RESULTS Compared to women with a normal BMI in their first pregnancy, those who were underweight prepregnancy had increased odds for preterm birth by 20% and small for gestational age by 40% in their second pregnancy, while those with prepregnancy obesity had increased odds for large for gestational age, preeclampsia, cesarean delivery, and neonatal deaths in their second pregnancy by 54%, 156%, 85%, and 37%, respectively. CONCLUSION Women starting a first pregnancy with suboptimal BMI may be at risk of adverse maternal and fetal outcomes in a subsequent pregnancy, even if their first pregnancy was uncomplicated or if they reached a normal weight by their second pregnancy. The long-term consequences of suboptimal BMI carry considerable public health implications.

Association Between Physical Activity and Insomnia Symptoms in Rural Communities of Southeastern Missouri, Tennessee, and Arkansas

PURPOSE The purpose of this study is to examine whether physical activity is associated with less insomnia symptoms in the rural communities. METHODS This study used cross-sectional data collected from a 2005 telephone survey for evaluation of a community walking trails intervention to promote physical activity in rural communities including 6 communities in the Missouri Ozark region and 6 communities in Arkansas and Tennessee (n = 1,234). The exposure variable is self-reported regular current physical activity. The outcome includes symptoms of insomnia operationalized as having trouble falling asleep, staying asleep, and waking up too early nearly every day. Logistic regression was used to calculate prevalence odds ratios (PORs) and 95% confidence intervals (95% CI). FINDINGS The study sample includes mostly white (95%), married (62%), overweight/obese (61%) women with a high school degree and a mean age of 54. Fourteen percent of participants reported having insomnia symptoms. Self-report of currently being physically active regularly was associated with decreased odds of insomnia symptoms (adjusted POR: .37; 95% CI, 0.14-0.99) among participants with under or normal body weight, after controlling for age, gender, education level, marital status, and chronic diseases. There was also a negative linear correlation between the number of days and total minutes of vigorous physical activity and insomnia symptoms. CONCLUSIONS In these rural communities, we observed a significant relationship between regular physical activity and decreased insomnia symptoms.

Ambient air pollution the risk of stillbirth: A prospective birth cohort study in Wuhan, China

BACKGROUND Recent studies suggest that ambient air pollution exposure during pregnancy is associated with stillbirth occurrence. However, the results on the associations between ambient air pollutants and stillbirths are inconsistent and little is known about the gestational timing of sensitive periods for the effects of ambient air pollutants exposure on stillbirth. OBJECTIVE This study aimed to examine whether exposure to high levels of ambient air pollutants in a Chinese population is associated with an increased risk of stillbirth, and determine the gestational period when the fetus is most susceptible. METHODS We conducted a population-based cohort study in Wuhan, China, involving 95,354 births between June 10, 2011 and June 9, 2013. The exposure assessments were based on the daily mean concentrations of air pollutants obtained from the exposure monitor nearest to the pregnant womens residence. Logistic regression analyses were performed to determine the associations between stillbirths and exposure to each of the air pollutants at different pregnancy periods with adjustment for confounding factors. RESULTS Stillbirth increased with a 10 μg/m3 increase in particulate matter 2.5 (PM2.5) in each stage of pregnancy, and a significant association between carbon monoxide (CO) exposure and stillbirth was found during the third trimester (adjusted odds ratio (aOR): 1.01, 95% confidence interval (CI): 1.00-1.01) and in the entire pregnancy (aOR: 1.18, 95% CI: 1.04-1.34). Furthermore, an increased risk of stillbirth in the third trimester was associated with a 10 μg/m3 increase in PM10 (aOR: 1.08, 95% CI: 1.04-1.11), nitrogen dioxide (NO2) (aOR: 1.13, 95% CI: 1.07-1.21) and sulfur dioxide (SO2) (aOR: 1.26, 95% CI: 1.16-1.35). However, no positive association was observed between ozone exposure and stillbirth. In the two-pollutant models, PM2.5 and CO exposures were found to be consistently associated with stillbirth. CONCLUSIONS Our study revealed that exposure to high levels of PM2.5, PM10, SO2, NO2 and CO increases the risk of stillbirth and the most susceptible gestational period to ambient air pollution exposure was in the third trimester. Further toxicological and prospective cohort studies with improved exposure assessments are needed to confirm the causal link between air pollutants and stillbirth.

Gestational Weight Gain in the First Two Pregnancies and Perinatal Outcomes in the Second Pregnancy

BACKGROUND Gestational Weight Gain (GWG) below or above the Institute of Medicine (IOM) recommendations increases the risk of adverse pregnancy outcomes. However, it remains unknown whether the risk of adverse outcomes is affected by GWG in a previous pregnancy. We examined associations between GWG in the index (second) pregnancy and pregnancy outcomes, including preterm delivery and small for gestational age (SGA), while taking into consideration GWG in the first pregnancy. METHODS In a population-based cohort study (n = 210 564), using the Missouri maternally-linked birth registry (1989-2005), we used multivariable Poisson regression with robust error variance stratified by prepregnancy body mass index (BMI) to evaluate associations between GWG in the index pregnancy and a composite indicator of GWG in the first and second pregnancies and our outcomes of interest, after controlling for sociodemographic and pregnancy-related confounders. RESULTS Associations between GWG in the index pregnancy and pregnancy outcomes were moderated by GWG in the first pregnancy. Despite having GWG within recommendations in the index pregnancy, women had increased risk of preterm delivery and SGA if they had suboptimal GWG in their first pregnancy. Also, women having suboptimal GWG in the index pregnancy had increased risk of preterm delivery only if their GWG in the first pregnancy was also suboptimal. CONCLUSIONS The observation that women who have GWG within recommendations in a current pregnancy may still have increased risk of adverse outcomes if they had suboptimal GWG in the first pregnancy has considerable clinical and public health implications.