Obesity: Siega-Riz AM

Anonymous00043, Anonymous00044, Siega-Riz AM, King JC. · No affiliation provided · J Am Diet Assoc. · Pubmed #19412993 No free full text.

Abstract: Given the detrimental influence of maternal overweight and obesity on reproductive and pregnancy outcomes for the mother and child, it is the position of the American Dietetic Association and the American Society for Nutrition that all overweight and obese women of reproductive age should receive counseling on the roles of diet and physical activity in reproductive health prior to pregnancy,during pregnancy, and in the inter conceptional period, in order to ameliorate these adverse outcomes. The effect of maternal nutritional status prior to pregnancy on reproduction and pregnancy outcomes is of great public health importance. Obesity in the United States and worldwide has grown to epidemic proportions, with an estimated 33% of US women classified as obese. This position paper has two objectives: (a) to help nutrition professionals become aware of the risks and possible complications of overweight and obesity for fertility,the course of pregnancy, birth outcomes, and short- and long-term maternal and child health outcomes;and (b) related to the commitment to research by the American Dietetic Association and the American Society for Nutrition, to identify the gaps in research to improve our knowledge of the risks and complications associated with being overweight and obese before and during pregnancy.Only with an increased knowledge of these risks and complications can health care professionals develop effective strategies that can be implemented before and during pregnancy as well as during the inter conceptional period to ameliorate adverse outcomes.

Siega-Riz AM, Herring AH, Olshan AF, Smith J, Moore C, Anonymous00045. · Department of Epidemiology, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516-3997, USA. · Paediatr Perinat Epidemiol. · Pubmed #19228314 No free full text.

Abstract: Young maternal age has been associated with an increased risk of gastroschisis, while high maternal weight status has been associated with a decreased risk. We were interested in investigating the joint effect of these two risk factors to identify thresholds in risk associated with body mass index (BMI) for a given age. Data from the National Birth Defects Prevention Study included 464 case infants with gastroschisis and 4842 healthy controls. A generalised additive model with a bivariate spline for continuous maternal age and prepregnancy BMI was used to model the probability of gastroschisis. The bivariate spline in BMI and maternal age was significantly associated with gastroschisis (P = 0.0001) after adjustment for study centre, maternal race/ethnicity, education, income and number of persons supported by income, smoking, alcohol use, vitamin use, vasoconstrictor medication use and gestational diabetes. The data indicate that women who are younger and who have lower BMI are at the greatest risk; a woman with a BMI of 17 who gives birth at age 15 has 7 times the odds (adjusted odds ratio = 7.0 [95% CI 4.2, 11.5]) of having an offspring with gastroschisis compared with a woman of age 24 with a BMI of 23. Furthermore, there was an interaction between maternal age and BMI for this risk. The increased risk of low maternal age and prepregnancy BMI associated with gastroschisis appears to suggest an aetiological role related to biological immaturity for this particular birth defect.

Siega-Riz AM, Siega-Riz AM, Laraia B. · Department of Nutrition, School of Public Health, University of North Carolina, Chapel Hill, North Carolina, USA. · Matern Child Health J. · Pubmed #16927160 links to  free full text

Abstract: The increasing prevalence of overweight and obesity among women of childbearing age is a growing public health concern in the United States. The average body mass index (BMI) is increasing among all age categories and women enter pregnancy at higher weights. Women are also more likely to retain gestational weight with each pregnancy. Women who are overweight (BMI 25-30) and obese (BMI >/=30) are at greater risk of adverse reproductive health outcomes compared to women of normal weight status (BMI 19.8-25). This article provides an overview of the complications associated with maternal overweight and obesity including diabetes, pre-eclampsia, c-sections, and birth defects. We present updated information on the weight trends among women. Finally, we present an overview of the prevention studies aimed at adolescents and women prior to pregnancy.

Siega-Riz AM, Siega-Riz AM, Laraia B. · Department of Nutrition, School of Public Health, University of North Carolina, Chapel Hill, North Carolina, USA. · Matern Child Health J. · Pubmed #16927160 links to  free full text

Abstract: The increasing prevalence of overweight and obesity among women of childbearing age is a growing public health concern in the United States. The average body mass index (BMI) is increasing among all age categories and women enter pregnancy at higher weights. Women are also more likely to retain gestational weight with each pregnancy. Women who are overweight (BMI 25-30) and obese (BMI >/=30) are at greater risk of adverse reproductive health outcomes compared to women of normal weight status (BMI 19.8-25). This article provides an overview of the complications associated with maternal overweight and obesity including diabetes, pre-eclampsia, c-sections, and birth defects. We present updated information on the weight trends among women. Finally, we present an overview of the prevention studies aimed at adolescents and women prior to pregnancy.

Siega-Riz AM, Evenson KR, Dole N. · Department of Maternal and Child Health, School of Public Health, Carolina Population Center, University of North Carolina, Chapel Hill, NC 27516, USA. · Nutr Rev. · Pubmed #15387475 No free full text.

Abstract: Past research on maternal weight gain during pregnancy has focused on determinants and consequences of inadequate weight gain with concerns for the health of the infant. However, with the rising prevalence of obesity among women of childbearing ages and the high proportion of women who are gaining in excess of recommendations, a shift in research focus must occur to include consideration of the mother's long-term health status. The few studies that have examined determinants of excessive weight gain and postpartum weight retention in this country were not comprehensive in assessing diet, physical activity and psychosocial factors and suffer from small sample sizes. Information is lacking concerning pregnant women's perceptions about eating and gaining weight, what they actually eat, how consumption and exercise relate to weight gain, and how psychosocial factors influence these behaviors during pregnancy. Likewise, little is known concerning these same attitudes and behaviors during the postpartum period that may contribute to weight retention.

Visness CM, London SJ, Daniels JL, Kaufman JS, Yeatts KB, Siega-Riz AM, Liu AH, Calatroni A, Zeldin DC. · Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. · J Allergy Clin Immunol. · Pubmed #19230960 No free full text.

Abstract: BACKGROUND: The prevalence of both obesity and allergic disease has increased among children over the last several decades. Previous literature on the relationship between obesity and allergic disease has been inconsistent. It is not known whether systemic inflammation could be a factor in this relationship. OBJECTIVE: We sought to examine the association of obesity with total and allergen-specific IgE levels and allergy symptoms in US children and adolescents and to assess the role of C-reactive protein. METHODS: National Health and Nutrition Examination Survey data from 2005-2006 included measurement of total and allergen-specific IgE levels and allergy questions. Overweight was defined as the 85th or greater to less than the 95th percentile of body mass index for age, and obesity was defined as the 95th percentile or greater. Linear and logistic regression models were used to examine the association of weight categories with total IgE levels, atopy, allergen-specific IgE levels, and allergy symptoms among youth aged 2 to 19 years. RESULTS: Geometric mean total IgE levels were higher among obese (geometric mean ratio, 1.31; 95% CI, 1.10-1.57) and overweight (ratio, 1.25; 95% CI, 1.02-1.54) children than among normal-weight children. The odds ratio (OR) for atopy (any positive specific IgE measurement) was increased in the obese children compared with that seen in those of normal weight; this association was driven largely by allergic sensitization to foods (OR for atopy, 1.26 [95% CI, 1.03-1.55]; OR for food sensitization, 1.59 [95% CI, 1.28-1.98]). C-reactive protein levels were associated with total IgE levels, atopy, and food sensitization. CONCLUSIONS: Obesity might be a contributor to the increased prevalence of allergic disease in children, particularly food allergy. Systemic inflammation might play a role in the development of allergic disease.

Laraia BA, Siega-Riz AM, Dole N, London E. · Department of Medicine, University of California, San Francisco, San Francisco, California, USA. · Obesity (Silver Spring). · Pubmed #19131943 No free full text.

Abstract: The objective of this study was to investigate the association of pregravid weight status, previous dietary restraint, and psychosocial factors during pregnancy. We used data from the Pregnancy, Infection, and Nutrition study, which recruited 2,006 women at prenatal clinics before 20 weeks' gestation who were >16 years and English speaking. Institute of Medicine BMI cut points of underweight (<19.8), normal weight (19.8-26.0), overweight (>26.0-29.0), obese (>29.0-34.9), and an additional category extremely obese (> or =35.0), were used to categorize weight status. Eight psychosocial measures and dietary restraint were assessed with regard to BMI; perceived stress, trait anxiety, depressive symptoms, internal locus of control (LOC), chance LOC, powerful others LOC, self-esteem, and mastery. Linear regression was used to estimate associations, controlling for potential confounders. A significant trend was found between increasing pregravid weight categories and increasing scores for perceived stress, trait anxiety, depressive symptoms, powerful others LOC and dietary restraint, and decreasing scores for self-esteem and mastery. In adjusted models, pregravid obesity was independently associated with perceived stress, trait anxiety, and depressive symptoms. Extreme obesity was independently associated with all measures except internal LOC. A strong linear association was found between increasing weight categories and dietary restraint. In conclusion, as pregravid weight increased, pregnant women were at greater risk of reporting higher scores on negative psychosocial state and dietary restraints, and reporting lower score on positive personal dispositions.

Webb JB, Siega-Riz AM, Dole N. · Department of Psychology, UNC Charlotte, Charlotte, North Carolina, USA. · Obesity (Silver Spring). · Pubmed #19008871 No free full text.

Abstract: Pregnancy is a critical time window for evaluating weight gain on subsequent risk for obesity among women of childbearing age. The purpose of this investigation was to determine whether symptoms of depression, anxiety, stress, self-esteem, and fetal health locus of control (FHLC) beliefs were significant risk factors for adequacy of gestational weight gain (GWG) when maternal sociodemographic characteristics and health behaviors were considered. A total of 1,605 women were prospectively followed from < or =20 weeks' gestation through delivery. Participants completed standard self-report questionnaires. Adequacy of GWG was expressed as the ratio of observed/expected weight gain based on Institute of Medicine recommendations. Multivariate ANOVA models were conducted and generalized linear models were performed to calculate risk ratios. Higher depressive symptoms reported throughout pregnancy were significantly associated with higher adequacy ratios. Stronger beliefs in chance in determining fetal health predicted inadequate relative to adequate GWG and was positively associated with larger GWG ratios overall. Several relationships were attenuated when adjusted for covariates. The relationship between psychosocial status and adequacy of GWG is significantly impacted by maternal sociodemographic factors and health practices engaged in during pregnancy. Women who tend to believe that external factors primarily determine fetal health appear to be more vulnerable to nonadherence to clinical GWG guidelines. These results have important implications for targeting prevention and intervention efforts for improving maternal and fetal outcomes secondary to GWG patterns.

Mumford SL, Siega-Riz AM, Herring A, Evenson KR. · Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27599-7435, USA. · J Am Diet Assoc. · Pubmed #18926129 No free full text.

Abstract: OBJECTIVE: To determine whether a history of preconceptional dieting and restrained eating was related to higher weight gains in pregnancy. DESIGN: Dieting practices were assessed among a prospective cohort of pregnant women using the Revised Restraint Scale. Women were classified on three separate subscales as restrained eaters, dieters, and weight cyclers. SUBJECTS: Participants included 1,223 women in the Pregnancy, Infection, and Nutrition Study. MAIN OUTCOME MEASURES: Total gestational weight gain and adequacy of weight gain (ratio of observed/expected weight gain based on Institute of Medicine recommendations). STATISTICAL ANALYSES PERFORMED: Multiple linear regression was used to model the two weight-gain outcomes, while controlling for potential confounders including physical activity and weight-gain attitudes. RESULTS: There was a positive association between each subscale and total weight gain, as well as adequacy of weight gain. Women classified as cyclers gained an average of 2 kg more than noncyclers and showed higher observed/expected ratios by 0.2 units. Among restrained eaters and dieters, there was a differential effect by body mass index. With the exception of underweight women, all other weight status women with a history of dieting or restrained eating gained more weight during pregnancy and had higher adequacy of weight gain ratios. In contrast, underweight women with a history of restrained eating behaviors gained less weight compared to underweight women without those behaviors. CONCLUSIONS: Restrained eating behaviors were associated with weight gains above the Institute of Medicine's recommendations for normal, overweight, and obese women, and weight gains below the recommendations for underweight women. Excessive gestational weight gain is of concern because of its association with postpartum weight retention. The dietary restraint tool is useful for identifying women who would benefit from nutritional counseling prior to or during pregnancy with regard to achieving targeted weight-gain recommendations.

Deierlein AL, Siega-Riz AM, Herring A. · Department of Nutrition, University of North Carolina School of Public Health, Chapel Hill, NC 27514, USA. · Am J Clin Nutr. · Pubmed #18779285 No free full text.

Abstract: BACKGROUND: Most pregnant women gain more weight than the ranges recommended. Excessive weight gain is linked to pregnancy complications and to long-term maternal and child health outcomes. OBJECTIVE: The objective was to examine the impact of dietary glycemic load and energy density on total gestational weight gain and the weight gain ratio (observed weight gain/expected weight gain). DESIGN: Data are from 1231 women with singleton pregnancies who participated in the Pregnancy, Infection, and Nutrition Cohort Study. Dietary information was collected at 26-29 wk of gestation with the use of a semiquantified food-frequency questionnaire. Linear regression models were used to estimate the associations between quartiles of glycemic load and energy density with total gestational weight gain and weight gain ratio. RESULTS: Dietary patterns of pregnant women significantly differed across many sociodemographic and behavioral characteristics, with the greatest contrasts seen for glycemic load. After adjustment for covariates, compared with women in the first quartile consuming a mean dietary energy density of 0.71 kcal/g (reference), women in the third quartile consuming a mean energy density of 0.98 kcal/g gained an excess of 1.13 kg (95% CI: 0.24, 2.01), and women in the fourth quartile consuming a mean energy density of 1.21 kcal/g gained an excess of 1.08 kg (95% CI: 0.20, 1.97) and had an increase of 0.13 (95% CI: 0.006, 0.24) units in the weight gain ratio. All other comparisons of energy intakes were not statistically significant. Glycemic load was not associated with total gestational weight gain or weight gain ratio. CONCLUSION: Dietary energy density is a modifiable factor that may assist pregnant women in managing gestational weight gains.

Evenson KR, Moos MK, Carrier K, Siega-Riz AM. · Department of Epidemiology, School of Public Health, University of North Carolina, Chapel Hill, 137 East Franklin Street, Bank of America Center, Suite 306, Chapel Hill, NC 27514, USA. · Matern Child Health J. · Pubmed #18478322 No free full text.

Abstract: OBJECTIVE: Physical activity generally declines during pregnancy, but barriers to activity during this time period are not well understood. The objective was to examine barriers to physical activity in a large cohort of pregnant women and to explore these barriers in more depth with qualitative data derived from a separate focus group study using a socioecologic framework. METHOD: A total of 1535 pregnant women (27-30 weeks' gestation) enrolled in the Pregnancy, Infection, and Nutrition Study were asked an open-ended question about their primary barrier to physical activity; responses were coded into categories according to the socioecologic framework. To further elucidate, 13 focus groups of a total of 58 pregnant women (20-37 weeks' gestation) were conducted among Hispanic, African American, and White participants. RESULTS: Among the 1535 pregnant women participating in the survey, 85% reported an intrapersonal barrier to physical activity, of which almost two-thirds were health related. Only 2% of the women reported their main barrier to physical activity as interpersonal and 3% reported a neighborhood or environmental barrier. These results were supported by the focus group data, overall and by race/ethnicity and body mass index. Although women discussed barriers to physical activity at a variety of levels, the intrapersonal level was the most frequently cited and discussed factor in both studies. CONCLUSIONS: Since pregnancy may trigger the development of obesity and since physical activity is recommended for healthy pregnant women, it is imperative to promote physical activity in a more relevant way. These quantitative and qualitative studies revealed many barriers to physical activity among pregnant women and some suggestions for interventions.

Waller DK, Shaw GM, Rasmussen SA, Hobbs CA, Canfield MA, Siega-Riz AM, Gallaway MS, Correa A, Anonymous00185. · School of Public Health, The University of Texas at Houston, Houston, TX 77030, USA. · Arch Pediatr Adolesc Med. · Pubmed #17679655 links to  free full text

Abstract: OBJECTIVE: To describe the relation between maternal obesity, overweight and underweight status, and 16 categories of structural birth defects. DESIGN: An ongoing multisite, case-control study. Clinical geneticists reviewed all of the cases, excluding those that had or were strongly suspected to have a single-gene disorder or chromosomal abnormality. Mothers with preexisting diabetes were also excluded. Body mass index was based on maternal report of height and weight prior to pregnancy. SETTING: Eight participating states in the United States. PARTICIPANTS: Mothers enrolled in the National Birth Defects Prevention Study who had index pregnancies between October 1, 1997, and December 31, 2002. MAIN EXPOSURE: Maternal obesity. MAIN OUTCOME MEASURES: Crude and adjusted odds ratios. RESULTS: Mothers of offspring with spina bifida, heart defects, anorectal atresia, hypospadias, limb reduction defects, diaphragmatic hernia, and omphalocele were significantly more likely to be obese than mothers of controls, with odds ratios ranging between 1.33 and 2.10. Mothers of offspring with gastroschisis were significantly less likely to be obese than mothers of controls. CONCLUSIONS: To our knowledge, this is the first population-based study of its scale to examine prepregnancy obesity and a range of structural birth defects. These results suggest a weak to moderate positive association of maternal obesity with 7 of 16 categories of birth defects and a strong inverse association with gastroschisis. The mechanisms underlying these associations are not yet understood but may be related to undiagnosed diabetes.

Laraia BA, Bodnar LM, Siega-Riz AM. · Department of Medicine, Center for Health and Community, University of California, San Francisco, CA 94118, USA. · Public Health Nutr. · Pubmed #17381955 No free full text.

Abstract: OBJECTIVE: To investigate the association between pregravid weight status and diet quality. DESIGN: Institute of Medicine body mass index (BMI) cut-off points of 26.0-29.0 kg m- 2 for overweight and >29 kg m- 2 for obese were used to categorise women's weight status. Dietary information was obtained by self-report at 26-28 weeks' gestation using a modified Block food-frequency questionnaire. The Diet Quality Index for Pregnancy (DQI-P) included: servings of grains, vegetables and fruits, folate, iron and calcium intake, percentage calories from fat, and meal pattern score. Multinomial logistic regression models were used to estimate the association between weight status and tertiles of DQI-P controlling for potential individual confounders. SETTING: A clinical-based population recruited through four prenatal clinics in central North Carolina. SUBJECTS: A total of 2394 women from the Pregnancy, Infection and Nutrition study were included in this analysis. RESULTS: Evidence of a dose-response relationship was found between BMI and inadequate servings of grains and vegetables, and iron and folate intake. Pregravid obesity was associated with 76% increased odds of falling into the lowest diet quality tertile compared with underweight women after controlling for potential confounders. CONCLUSION: A modest association was found between pregravid weight status and diet quality. If corroborated, these findings suggest that overweight pregnant women should be targeted for nutrition counselling interventions aimed to improve diet quality.

Vahratian A, Siega-Riz AM, Savitz DA, Zhang J. · Department of Maternal and Child Health, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. · Ann Epidemiol. · Pubmed #15921926 No free full text.

Abstract: PURPOSE: To examine the effect of maternal pre-pregnancy overweight and obesity on the risk of term cesarean delivery in nulliparous women. METHODS: The authors examined data from 641 nulliparous women with a term pregnancy that participated in the Pregnancy, Infection, and Nutrition Study from 1995 to 2002. Unadjusted and adjusted risk ratios and 95% confidence intervals (CI) were computed for normal weight (BMI 19.8-26.0 kg/m(2)), overweight (BMI 26.1-29.0 kg/m(2)), and obese (BMI>29.0 kg/m(2)) women. Normal weight women served as the referent population. RESULTS: The unadjusted risk ratio for cesarean delivery for overweight women compared with normal weight women was 1.4 (95% CI, 0.97, 2.1) and for obese women compared with normal weight women was 1.4 (95% CI, 1.03, 2.0). After controlling for maternal height, education, weight gain during pregnancy, and labor induction, the adjusted risk ratio for cesarean delivery among overweight women was 1.2 (95% CI, 0.8, 1.8). The adjusted risk ratio for obese women was 1.5 (95% CI, 1.05, 2.0). CONCLUSION: Our analysis confirms that there is a moderate association between maternal pre-pregnancy obesity and an unplanned term cesarean delivery. However, the risk is not as large as previously reported.

Satia JA, Galanko JA, Siega-Riz AM. · Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. · Public Health Nutr. · Pubmed #15548348 No free full text.

Abstract: OBJECTIVE: To examine associations of the frequency of eating at fast-food restaurants with demographic, behavioural and psychosocial factors and dietary intake in African American adults. METHODS: Self-reported data from a population-based cross-sectional survey of 658 African Americans, aged 20-70 years, in North Carolina. An 11-page questionnaire assessed eating at fast-food restaurants, demographic, behavioural and diet-related psychosocial factors, and dietary intake (fruit, vegetable, total fat and saturated fat intakes, and fat-related dietary behaviours). RESULTS: The participants were aged 43.9+/-11.6 years (mean+/-standard deviation), 41% were male, 37% were college graduates and 75% were overweight or obese. Seventy-six per cent reported eating at fast-food restaurants during the previous 3 months: 4% usually, 22% often and 50% sometimes. Frequency of eating at fast-food restaurants was positively associated with total fat and saturated fat intakes and fat-related dietary behaviours (P<0.0001) and inversely associated with vegetable intake (P<0.05). For example, mean daily fat intake was 39.0 g for usually/often respondents and 28.3 g for those reporting rare/never eating at fast-food restaurants. Participants who reported usual/often eating at fast-food restaurants were younger, never married, obese, physically inactive and multivitamin non-users (all P<0.01). Frequency of eating at fast-food restaurants was positively associated with fair/poor self-rated health, weak belief in a diet-cancer relationship, low self-efficacy for healthy eating, weight dissatisfaction, and perceived difficulties of preparing healthy meals and ordering healthy foods in restaurants (all P<0.05). Frequency of eating at fast-food restaurants did not differ significantly by sex, education, smoking, ability to purchase healthy foods or knowledge of the Food Guide Pyramid. CONCLUSIONS: Eating at fast-food restaurants is associated with higher fat and lower vegetable intakes in African Americans. Interventions to reduce fast-food consumption and obesity in African Americans should consider demographic and behavioural characteristics and address attitudes about diet-disease relationships and convenience barriers to healthy eating.

Vahratian A, Zhang J, Troendle JF, Savitz DA, Siega-Riz AM. · Department of Maternal and Child Health, School of Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA. · Obstet Gynecol. · Pubmed #15516383 No free full text.

Abstract: OBJECTIVE: To examine the effect of maternal overweight and obesity on labor progression. METHODS: We analyzed data from 612 nulliparous women with a term pregnancy that participated in the Pregnancy, Infection, and Nutrition Study from 1995 to 2002. The median duration of labor by each centimeter of cervical dilation was computed for normal-weight (body mass index [BMI] 19.8-26.0 kg/m2), overweight (BMI 26.1-29.0 kg/m2), and obese (BMI > 29.0 kg/m2) women and used as a measurement of labor progression. RESULTS: After adjusting for maternal height, labor induction, membrane rupture, oxytocin use, epidural analgesia, net maternal weight gain, and fetal size, the median duration of labor from 4 to 10 cm was significantly longer for both overweight and obese women, compared with normal-weight women (7.5, 7.9, and 6.2 hours, respectively). For overweight women, the prolongation was concentrated around 4-6 cm, whereas for obese women, their labor was significantly slower before 7 cm. CONCLUSION: Labor progression in overweight and obese women was significantly slower than that of normal-weight women before 6 cm of cervical dilation. Given that nearly one half of women of childbearing age are either overweight or obese, it is critical to consider differences in labor progression by maternal prepregnancy BMI before additional interventions are performed.

Bodnar LM, Siega-Riz AM, Cogswell ME. · Magee-Women's Research Institute, Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of Pittsburgh, 204 Craft Avenue, PA 15213, USA. · Obes Res. · Pubmed #15229333 No free full text.

Abstract: OBJECTIVE: To assess the independent effect of prepregnancy BMI on the risk of postpartum anemia. RESEARCH METHODS AND PROCEDURES: Pregnant women from North Carolina who enrolled in the Iron Supplementation Study at their first prenatal visit at <20 weeks gestation and who delivered a live infant were followed to the postpartum visit (n = 439). BMI had a curvilinear relation in the logit of postpartum anemia; therefore, a restricted quadratic spline with three knots at the inflection points was used to specify BMI. Multiple log binomial regression was used to quantify the relation between prepregnancy BMI and postpartum anemia after adjusting for maternal ethnicity/race, education, smoking, initial hemoglobin concentration, and prenatal iron supplementation. RESULTS: Prevalence of postpartum anemia was 19.1%. After adjusting for confounders, we found that risk of postpartum anemia was similar for women with BMI values from 17 to 24 compared with women with a BMI of 20. Adjusted relative risk increased as BMI increased from 24 to 38. Women with a BMI of 28 had approximately 1.8 times the postpartum anemia risk of a woman with a BMI of 20 (95% confidence interval 1.3, 2.5), and obese women with a BMI of 36 had approximately 2.8 times the risk (95% confidence interval 1.7, 4.7). DISCUSSION: These data suggest that high prepregnancy BMI substantially increases the risk of postpartum anemia. Postpartum anemia screening and iron supplementation of overweight and obese women may be warranted.

Laraia BA, Siega-Riz AM, Evenson KR. · Department of Nutrition, Carolina Population Center, University of North Carolina, CB# 8120, Chapel Hill, NC 27599, USA. · Prev Med. · Pubmed #14715209 No free full text.

Abstract: BACKGROUND: A causal relationship between hunger and obesity has been postulated. Two cross-sectional studies have found evidence to suggest an association between obesity and food insecurity among adult women, and a third study suggests an association between underweight and food insecurity among men. The purpose of this study was to investigate the association between concern about enough food and obesity in an adult population at the state level. METHODS: A cross-sectional analysis was conducted using 1999 data from the Behavioral Risk Factor Surveillance System (BRFSS), Social Context Module (n = 3,945). RESULTS: An 8.0% prevalence of concern about enough food was found in Louisiana, and an 11.8% prevalence was found in New York, and was positively associated with morbid obesity, RR = 2.20 (95% CI = 1.24, 3.90) and RR = 2.23 (95% CI = 1.30, 3.84), respectively. However, this association became nonsignificant after controlling for education, income, race/ethnicity, marital status, and general health. CONCLUSION: A very strong apparent relationship between concern about enough food and obesity could be entirely accounted for by the influences of socioeconomic variables. This emphasizes the need for longitudinal research studies using precise measures of weight, height, and food security.

Bodnar LM, Siega-Riz AM, Miller WC, Cogswell ME, McDonald T. · Department of Nutrition, School of Public Health and School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27516-2524 USA. · Am J Epidemiol. · Pubmed #12419762 links to  free full text

Abstract: The authors evaluated the utility of selective screening criteria for postpartum anemia developed by the Centers for Disease Control and Prevention (CDC) versus criteria developed among low-income women using prevalence-based screening principles. Pregnant women in Raleigh, North Carolina, were followed up to the postpartum visit in 1997-1999 (n = 345). Prevalence of postpartum anemia was 19.1%. Independent risk markers, arrived at through multivariate logistic regression, were multiparity (odds ratio (OR) = 1.5, 95% confidence interval (CI): 0.8, 2.9), obesity (OR = 3.0, 95% CI: 1.6, 5.5), anemia at 24-29 weeks' gestation (OR = 2.3, 95% CI: 1.2, 4.4), anemia before delivery (OR = 3.4, 95% CI: 1.8, 6.7), and not exclusively breastfeeding (OR = 2.8, 95% CI: 1.0, 7.7). Risk scores were calculated by counting risk markers present. Likelihood ratios were determined for all possible risk scores of our algorithm and CDC's algorithm. Anemia screening decisions differed depending on clinic anemia prevalence. For example, if low test thresholds are assumed, when clinic prevalence is 10%, women with risk scores >3 on the authors' algorithm and >0 on CDC's algorithm should be screened. The authors' algorithm, in combination with prevalence information, can save clinics more money than CDC's current algorithm because a broader range of likelihood ratios was obtained, indicating a better ability to distinguish high- from low-risk women. However, if resources are available, universal screening should be considered in high-prevalence settings.

Bodnar LM, Scanlon KS, Freedman DS, Siega-Riz AM, Cogswell ME. · Department of Nutrition, University of North Carolina School of Public Health, Chapel Hill, USA. · Am J Obstet Gynecol. · Pubmed #11518906 No free full text.

Abstract: OBJECTIVE: To determine the prevalence of anemia from 4 to 26 weeks post partum and to examine prenatal predictors of postpartum anemia. STUDY DESIGN: Retrospective cohort analysis of 59,428 participants in the Special Supplemental Nutrition Program for Women, Infants, and Children in 12 US states. RESULTS: The prevalence of postpartum anemia was 27%. Anemia rates were higher among minority women, reaching 48% among non-Hispanic black women. Of 9129 women who had normal hemoglobin in the third trimester, 21% had postpartum anemia. Prenatal anemia was the strongest predictor of postpartum anemia (adjusted odds ratio, 2.7; 95% confidence interval, 2.5-2.8). Maternal obesity, multiple birth, and not breast-feeding also predicted postpartum anemia. CONCLUSION: The high prevalence of post partum anemia among low-income women highlights the importance of anemia screening at 4 to 6 weeks post partum. These data suggest that screening should not be limited, as it is at present, to women considered at high risk.

Zizza C, Siega-Riz AM, Popkin BM. · Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27516-3997, USA. · Prev Med. · Pubmed #11304090 No free full text.

Abstract: BACKGROUND: Studies on children and adolescents suggest a large increase in the role of snacking; however, little is know about changes in the snacking behavior of young adults. METHODS: USDA's nationally representative surveys from 1977-1978 to 1994-1996 are used to study snacking trends among 8,493 persons 19-29 years old. RESULTS: Snacking prevalence increased from 77 to 84% between 1977-1978 and 1994-1996. The nutritional contribution of snacks to total daily energy intake went from 20 to 23%, primarily because energy consumed per snacking occasion increased by 26% and the number of snacks per day increased 14%. The mean daily caloric density (calorie per gram of food) of snacks increased from 1.05 to 1.32 calories. The energy contribution of high-fat desserts to the total calories from snacking decreased (22 to 14%), however, this food group remained the most important source of energy. The energy contribution of high-fat salty snacks doubled. Sweetened and alcoholic beverages remained important energy contributors. CONCLUSION: This large increase in total energy and energy density of snacks among young adults in the United States may be contributing to our obesity epidemic.