Association of postpartum depression with weight retention 1 year after childbirth

Objective: To examine the extent to which early postpartum depression is associated with weight retention 1 year after childbirth. Methods and Procedures: In a prospective cohort study of 850 women enrolled in Project Viva, mothers reported depressive symptoms on the Edinburgh Postnatal Depression Scale (EPDS) at midpregnancy and 6 months postpartum. A score >12 indicated probable depression. We assessed associations of antenatal and postpartum depression with risk of substantial weight retention (at least 5 kg) 1 year after childbirth. Results: Seven‐hundred thirty‐six women (87%) were not depressed during or after pregnancy, 55 (6%) experienced antenatal depression only, 22 (3%) experienced both antenatal and postpartum depression, and 37 (4%) experienced postpartum depression only. At 1 year, participants retained a mean of 0.6 kg (range ?16.4 to 25.5), and 12% retained at least 5 kg. In multivariate logistic regression analyses, after adjustment for weight‐related covariates, maternal sociodemographics, and parity, new‐onset postpartum depression was associated with more than a doubling of risk of retaining at least 5 kg (odds ratio (OR): 2.54, 95% confidence interval (CI): 1.06, 6.09). Antenatal depression, either alone or in combination with postpartum depression, was not associated with substantial weight retention. Discussion: New‐onset postpartum depression was associated with substantial weight retention in the first postpartum year. Interventions to manage depressive symptoms may help reduce excess weight retained postpartum and aid in the prevention of obesity among women.     

Maternal weight change from prepregnancy to 18 months postpartum and subsequent risk of hypertension and cardiovascular disease in Danish women: A cohort study

BackgroundOne-fourth of women experience substantially higher weight years after childbirth. We examined weight change from prepregnancy to 18 months postpartum according to subsequent maternal risk of hypertension and cardiovascular disease (CVD).Methods and findingsWe conducted a cohort study of 47,966 women with a live-born singleton within the Danish National Birth Cohort (DNBC; 1997–2002). Interviews during pregnancy and 6 and 18 months postpartum provided information on height, gestational weight gain (GWG), postpartum weights, and maternal characteristics. Information on pregnancy complications, incident hypertension, and CVD was obtained from the National Patient Register. Using Cox regression, we estimated adjusted hazard ratios (HRs; 95% confidence interval [CI]) for hypertension and CVD through 16 years of follow-up. During this period, 2,011 women were diagnosed at the hospital with hypertension and 1,321 with CVD. The women were on average 32.3 years old (range 18.0–49.2) at start of follow-up, 73% had a prepregnancy BMI <25, and 27% a prepregnancy BMI ≥25. Compared with a stable weight (±1 BMI unit), weight gains from prepregnancy to 18 months postpartum of >1–2 and >2 BMI units were associated with 25% (10%–42%), P = 0.001 and 31% (14%–52%), P < 0.001 higher risks of hypertension, respectively. These risks were similar whether weight gain presented postpartum weight retention or a new gain from 6 months to 18 months postpartum and whether GWG was below, within, or above the recommendations. For CVD, findings differed according to prepregnancy BMI. In women with normal-/underweight, weight gain >2 BMI units and weight loss >1 BMI unit were associated with 48% (17%–87%), P = 0.001 and 28% (6%–55%), P = 0.01 higher risks of CVD, respectively. Further, weight loss >1 BMI unit combined with a GWG below recommended was associated with a 70% (24%–135%), P = 0.001 higher risk of CVD. No such increased risks were observed among women with overweight/obesity (interaction by prepregnancy BMI, P = 0.01, 0.03, and 0.03, respectively). The limitations of this observational study include potential confounding by prepregnancy metabolic health and self-reported maternal weights, which may lead to some misclassification.ConclusionsPostpartum weight retention/new gain in all mothers and postpartum weight loss in mothers with normal-/underweight may be associated with later adverse cardiovascular health.

Helene Kirkegaard and co-workers study maternal weight changes and cardiovascular risk over 16 years of follow-up.     

Relapse to smoking and postpartum weight retention among women who quit smoking during pregnancy

Postpartum weight retention contributes to obesity risk in women. Given that most women who quit smoking as a result of pregnancy will resume smoking within 6 months postpartum and that there is a robust association between smoking and weight, we sought to evaluate postpartum weight retention as a function of postpartum smoking status among women who had quit smoking during pregnancy. Women (N = 183) with biochemically confirmed cigarette abstinence at the end of pregnancy were recruited between February 2003 and November 2006. Women self-reported demographic information and weight before pregnancy. Smoking status and weight were documented at the end of pregnancy and at 6, 12, and 24 weeks postpartum. Breastfeeding was reported at 6 weeks postpartum. Differences in weight retention by relapse status at each assessment were evaluated. To examine weight retention in the presence of conceptually relevant covariates, mixed models with log-transformed weight data were used. At 24 weeks postpartum, 34.6% of women remained abstinent. Women who remained abstinent throughout the 24-week period retained 4.7 ± 2.1 kg more than did women who had relapsed by 6 weeks postpartum, P = 0.03. This difference in postpartum weight retention was significant after controlling for relevant covariates (age, race, breastfeeding, and pregravid BMI). Resumption of smoking within the first 6 weeks following childbirth is associated with decreased postpartum weight retention, even after controlling for breastfeeding and pregravid weight. Interventions to sustain smoking abstinence postpartum might be enhanced by components designed to minimize weight retention.     

Beliefs about weight gain among young adults: potential challenges to prevention

This study assessed young adults' beliefs about weight gain with the goal of improving intervention efforts with this high-risk group. A total of 1,347 incoming freshman (45% male; 81% non-Hispanic white; 18.6 ± 1.7 years; BMI = 23.3 ± 2.3 kg/m2) at a large state university in the Northeast completed a survey designed to assess: (i) degree of concern about weight gain, (ii) level of interest in weight control programs, and (iii) the most acceptable setting for an intervention. Perceptions about freshman weight gain were consistent across gender, with men and women reporting that the average student gains 5.4 ± 1.9 kg and 5.6 ± 1.9 kg respectively. Men in general were less concerned about weight gain (P < 0.001) and reported they would have to gain 6.2 ± 4.2 kg before becoming concerned compared to 3.1 ± 1.7 kg among women (P < 0.001). Overweight (OW) men were more concerned about gaining weight than normal weight (NW) men (P < 0.001) and indicated they would have to gain less weight before becoming concerned (5.0 ± 3.0 kg vs. 6.7 ± 4.5 kg, P < 0.001). Fewer men reported they would join a program to prevent weight gain (17% men vs. 40% women, P < 0.001); the percentage of men willing to join a prevention program did not vary by weight status (P = 0.59). Both men and women were most likely to report a willingness to attend classes on a local college campus compared to other settings. Findings highlight the challenges of engaging young adults in weight gain prevention programs, particularly young men, and are discussed in terms of implications for improving recruitment efforts and intervention development with this population.     

Joint and Independent Associations of Gestational Weight Gain and Pre-Pregnancy Body Mass Index with Outcomes of Pregnancy in Chinese Women: A Retrospective Cohort Study

Objective

To explore the joint and independent effects of gestational weight gain (GWG) and pre-pregnancy body mass index (BMI) on pregnancy outcomes in a population of Chinese Han women and to evaluate pregnant women’s adherence to the 2009 Institute of Medicine (IOM) gestational weight gain guidelines.

Methods

This was a multicenter, retrospective cohort study of 48,867 primiparous women from mainland China who had a full-term singleton birth between January 1, 2011 and December 30, 2011. The independent associations of pre-pregnancy BMI, GWG and categories of combined pre-pregnancy BMI and GWG with outcomes of interest were examined using an adjusted multivariate regression model. In addition, women with pre-pregnancy hypertension were excluded from the analysis of the relationship between GWG and delivery of small-for-gestational-age (SGA) infants, and women with gestational diabetes (GDM) were excluded from the analysis of the relationship between GWG and delivery of large-for-gestational-age (LGA) infants.

Results

Only 36.8% of the women had a weight gain that was within the recommended range; 25% and 38.2% had weight gains that were below and above the recommended range, respectively. The contribution of GWG to the risk of adverse maternal and fetal outcomes was modest. Women with excessive GWG had an increased likelihood of gestational hypertension (adjusted OR 2.55; 95% CI = 1.92–2.80), postpartum hemorrhage (adjusted OR 1.30; 95% CI = 1.17–1.45), cesarean section (adjusted OR 1.31; 95% CI = 1.18–1.36) and delivery of an LGA infant (adjusted OR 2.1; 95% CI = 1.76–2.26) compared with women with normal weight gain. Conversely, the incidence of GDM (adjusted OR 1.64; 95% CI = 1.20–1.85) and SGA infants (adjusted OR 1.51; 95% CI = 1.32–1.72) was increased in the group of women with inadequate GWG. Moreover, in the obese women, excessive GWG was associated with an apparent increased risk of delivering an LGA infant. In the women who were underweight, poor weight gain was associated with an increased likelihood of delivering an SGA infant. After excluding the mothers with GDM or gestational hypertension, the ORs for delivery of LGA and SGA infants decreased for women with high GWG and increased for women with low GWG.

Conclusions

GWG above the recommended range is common in this population and is associated with multiple unfavorable outcomes independent of pre-pregnancy BMI. Obese women may benefit from avoiding weight gain above the range recommended by the 2009 IOM. Underweight women should avoid low GWG to prevent delivering an SGA infant. Pregnant women should therefore be monitored to comply with the IOM recommendations and should have a balanced weight gain that is within a range based on their pre-pregnancy BMI.     

Sleep duration and weight change in midlife women: The SWAN sleep study

Objective:

Short sleep duration has been associated with higher current BMI and subsequent weight gain. However, most prior longitudinal studies are limited by reliance on self‐reported sleep duration, and none accounted for the potential confounding effect of sleep‐disordered breathing. The associations of sleep duration with current BMI and BMI change were examined among 310 midlife women in the Study of Women's Health Across the Nation (SWAN) Sleep Study (2003‐2005).

Methods:

Sleep duration was assessed for approximately one month with concurrent wrist actigraphy and sleep diaries. The presence and severity of sleep‐disordered breathing was quantified using the apnea‐hypopnea index (AHI) based on in‐home polysomnography. BMI was assessed annually through core SWAN visit 10 (2006 and 2008).

Results:

Mean BMI increased from 29.6 (SD = 7.8) kg/m² to 30.0 (SD = 8.0) kg/m² over an average of 4.6 years (SD = 1.0) of follow‐up. In cross‐sectional analyses controlling for AHI, demographic variables, and several potential confounding variables, actigraphy (estimate = ‐1.22, 95% confidence interval (CI): ‐2.03, ‐0.42) and diary (estimate = ‐0.86, 95% CI ‐1.62, ‐0.09) measures of sleep duration were inversely associated with BMI. Each hour of less sleep was associated with 1.22 kg/m² greater BMI for actigraphy sleep duration, and a 0.86 kg/m² greater BMI for diary sleep duration. Longitudinal associations between sleep duration and annual BMI change were nonsignificant in unadjusted and fully adjusted models.

Conclusion:

In this cohort of midlife women, cross‐sectional associations between sleep duration and current BMI were independent of sleep‐disordered breathing, but sleep duration was not prospectively associated with weight change.     

Pre-Pregnancy BMI,Gestational Weight Gain,and the Risk of Hypertensive Disorders of Pregnancy: A Cohort Study in Wuhan,China

Background

Hypertensive disorders of pregnancy (HDP) are major causes of maternal death worldwide and the risk factors are not fully understood. Few studies have investigated the risk factors for HDP among Chinese women. A cohort study involving 84,656 women was conducted to investigate pre-pregnancy BMI, total gestational weight gain (GWG), and GWG during early pregnancy as risk factors for HDP among Chinese women.

Methods

The study was conducted between 2011–2013 in Wuhan, China, utilizing data from the Maternal and Children Healthcare Information Tracking System of Wuhan. A total of 84,656 women with a live singleton pregnancy were included. Multiple unconditional logistic regression was conducted to evaluate associations between putative risk factors and HDP.

Results

Women who were overweight or obese before pregnancy had an elevated risk of developing HDP (overweight: OR = 2.66, 95% CI = 2.32–3.05; obese: OR = 5.53, 95% CI = 4.28–7.13) compared to their normal weight counterparts. Women with total GWG above the Institute of Medicine (IOM) recommendation had an adjusted OR of 1.72 (95% CI = 1.54–1.93) for HDP compared to women who had GWG within the IOM recommendation. Women with gestational BMI gain >10 kg/m² during pregnancy had an adjusted OR of 3.35 (95% CI = 2.89–3.89) for HDP, compared to women with a gestational BMI gain <5 kg/m². The increased risk of HDP was also observed among women with higher early pregnancy (up to 18 weeks of pregnancy) GWG (>600g/wk: adjusted OR = 1.48, 95% CI = 1.19–1.84).

Conclusion

The results from this study show that maternal pre-pregnancy BMI, early GWG, and total GWG are positively associated with the risk of HDP. Weight control efforts before and during pregnancy may help to reduce the risk of HDP.     

Predictors of excessive and inadequate gestational weight gain in Hispanic women

Factors influencing gestational weight gain are incompletely understood, particularly among Hispanic women. We assessed medical, sociodemographic, behavioral, and psychosocial predictors of overall gestational weight gain, as well as gains below, within, or above the range recommended by the Institute of Medicine (IOM) within a prospective study of 770 Hispanic (predominantly Puerto Rican) prenatal care patients at a large tertiary care facility in Western Massachusetts. One third of women gained within the recommended range, 22% gained below, and 45% gained above the range. In multivariate analysis, women in the highest category of BMI (P(trend)<0.001) and parity (P(trend)<0.001) gained on average 9 lbs less than those in the lowest category. Increasing time in residence in the continental United States (P(trend)<0.01) as well as a number of prenatal care visits (P(trend)=0.03) were positively associated with weight gain. Overweight women (odds ratio (OR)=2.2, 95% confidence interval (CI) 1.3, 3.8) and those over age 30 years (OR=2.5, 95% CI 1.2, 5.0) were more likely to gain above the IOM range as compared to normal-weight women and those aged 20-24, respectively. Women with <10 years of residence in the United States were 50% less likely to gain above the IOM range as compared to third-generation women (95% CI 0.3, 0.9). Findings identify determinants of gestational weight gain which can form the basis of targeted interventions in this rapidly growing ethnic group.     

Association of Maternal Short Sleep Duration With Adiposity and Cardiometabolic Status at 3 Years Postpartum

The purpose of this study was to examine the association of short sleep duration among women in the first year postpartum with adiposity and cardiometabolic status at 3 years postpartum. We studied 586 women in Project Viva, a prospective cohort. At 6 months and 1 year postpartum, women reported the number of hours they slept in a 24‐h period, from which we calculated a weighted average of daily sleep. We used multivariable regression analyses to predict the independent effects of short sleep duration (≤5 h/day vs. >5 h/day) on adiposity, glucose metabolism, lipid metabolism, and adipokines at 3 years postpartum. Women's mean (s.d.) hours of daily sleep in the first year postpartum was 6.7 (0.97) h. After adjusting for age, race/ethnicity, education, parity, prepregnancy BMI, and excessive gestational weight gain, we found that postpartum sleep ≤5 h/day was associated with higher postpartum weight retention (β 1.50 kg; 95% confidence interval (CI): 0.02, 2.86), higher subscapular + triceps skinfold thickness (β 3.94 mm; 95% CI: 1.27, 6.60) and higher waist circumference (β 3.10 cm; 95% CI: 1.25, 4.94) at 3 years postpartum. We did not observe associations of short sleep duration with measures of cardiometabolic status at 3 years postpartum. In conclusion, short sleep duration in the first year postpartum is associated with higher adiposity at 3 years postpartum.     

Pretreatment weight change is associated with obesity treatment outcomes

Clinical experience suggests some individuals begin obesity treatment weighing more than they did at pretreatment assessment. Weight fluctuations between baseline screening and the first treatment session were examined among individuals enrolling in a group behavioral obesity treatment outcome study. Participants (N = 480, 94% female; 28% African American; M BMI = 35.7) were classified into those who started treatment having gained weight (≥ +1.15% above screening weight), lost weight (≤ -1.15% below screening weight) or remained weight stable. The majority of participants were weight-stable (61%) during the waiting period, but 23% lost weight (-2.36 ± 1.26 kg) and 16% gained weight (+2.11 ± 1.04 kg) between baseline screening and initiating treatment. Those who lost during the pretreatment period went on to have the greatest losses at 6-months (-8.9 ± 4.9 kg), with significantly greater weight losses than either the weight-stable (-6.1 ± 5.8 kg) or the weight-gain (-5.7 ± 5.8 kg) groups. Further, those who lost weight during the waiting period went on to attend a significantly higher proportion of treatment sessions and submitted more self-monitoring diaries than those who gained weight and those who stayed weight stable while waiting. Thus, pretreatment weight change was associated with treatment outcomes and may be relevant for research screening. Further, pretreatment weight change may be a clinical marker for likely success in behavioral weight control and as such warrants additional investigation to inform potential methods for enhancing outcomes for individuals in obesity treatment.     

Genetic Effects on Longitudinal Changes from Healthy to Adverse Weight and Metabolic Status — The HUNT Study

IntroductionThe complexity of obesity and onset and susceptibility of cardio-metabolic disorders are still poorly understood and is addressed here through studies of genetic influence on weight gain and increased metabolic risk longitudinally.Subjects/MethodsTwenty seven previously identified obesity, eating disorder or metabolic risk susceptibility SNPs were tested for association with weight or metabolically related traits longitudinally in 3999 adults participating both in the HUNT2 (1995–97) and HUNT3 (2006–08) surveys. Regression analyses were performed with changes from normal weight to overweight/obesity or from metabolically healthy to adverse developments with regards to blood pressure, glucose, HDL cholesterol, triglycerides or metabolic syndrome as outcomes. Additionally, a sub-sample of 1380 adolescents was included for testing association of nine SNPs with longitudinal weight gain into young adulthood.ResultsThe most substantial effect on BMI-based weight gain from normal to overweight/obesity in adults was observed for the DRD2 variant (rs6277)(OR: 0.79, 95% CI: 0.69–0.90, P = 3.9x10^-4, adj. P = 0.015). DRD2 was not associated with BMI on a cross-sectional level. In the adolescent sample, FTO (rs1121980) was associated with change to overweight at adulthood in the combined male-female sample (OR: 1.27, 95% CI: 1.09–1.49, P = 3.0x10^-3, adj. P = 0.019) and in females (OR: 1.53, 95% CI: 1.23–1.91, P = 1.8x10^-4, adj. P = 0.003). When testing for association to longitudinal adverse developments with regard to blood pressure, blood lipids and glucose, only rs964184 (ZNF259/APOA5) was significantly associated to unfavourable triglyceride changes (OR: 1.66, 95% CI: 1.36–2.03, P = 5.7x10^-7, adj. P = 0.001). Pleiotropic effects on metabolic traits, however, were observed for several genetic loci cross-sectionally, ZNF259/APOA5, LPL and GRB14 being the most important.Conclusions DRD2 exhibits effects on weight gain from normal weight to overweight/obesity in adults, while, FTO is associated to weight gain from adolescence to young adulthood. Unhealthy longitudinal triglyceride development is strongly affected by ZNF259/APOA. Our main finding, linking the DRD2 variant directly to the longitudinal weight gain observed, has not previously been identified. It suggests a genetic pre-disposition involving the dopaminergic signalling pathways known to play a role in food reward and satiety linked mechanisms.     

Implantable gastric stimulator does not prevent the increase in plasma ghrelin levels that occurs with weight loss

The SHAPE (Screened Health Assessment and Pacer Evaluation) trial was a 24 month randomized multicenter placebo-controlled study to determine the efficacy of an implantable gastric stimulator (IGS) for weight loss. This report is an investigator-initiated sub-study at one site designed to assess whether IGS affects plasma levels of ghrelin and peptide YY (PYY). The device was implanted in all subjects but was activated in the Treatment group (n = 7, BMI = 41.5 ± 2.0 kg/m2) and remained inactive in the Control (n = 6, BMI = 39.5 ± 1.7 kg/m2) during the first 12 months. IGS was activated in both groups during months 12-24. Fasting venous blood was drawn at months 0, 12, and 24 and an oral glucose tolerance test (OGTT) was performed at month 12. Although there was no difference in weight loss at 6 months (Control: -6.6 ± 1.5% vs. Treatment: -6.2 ± 1.4%), at 24 months the Control group exhibited weight gain from baseline (+2.2 ± 1.5%) that was significantly different from the weight loss in the Treatment group (-1.9 ± 1.4%; P < 0.05). At 12 months, fasting ghrelin was significantly increased (P < 0.05) in the Treatment group (285 ± 35 to 336 ± 35 pg/ml; weight change, -4.9 ± 1.4%), but not in the Control (211 ± 36 to 208 ± 35 pg/ml; weight change, -3.4 ± 1.5%). No significant change was observed in postprandial suppression of plasma ghrelin or in fasting and postprandial PYY levels. In conclusion, IGS does not prevent the increase in fasting plasma ghrelin levels associated with weight loss. Further studies are needed to determine whether changes in technology can improve weight loss and maintenance, perhaps using gut hormones as biomarkers of possible efficacy.     

Effect of diet and exercise, alone or combined, on weight and body composition in overweight-to-obese postmenopausal women

Lifestyle interventions for weight loss are the cornerstone of obesity therapy, yet their optimal design is debated. This is particularly true for postmenopausal women; a population with a high prevalence of obesity yet toward whom fewer studies are targeted. We conducted a year-long, 4-arm randomized trial among 439 overweight-to-obese postmenopausal sedentary women to determine the effects of a calorie-reduced, low-fat diet (D), a moderate-intensity, facility-based aerobic exercise program (E), or the combination of both interventions (D+E), vs. a no-lifestyle-change control (C) on change in body weight and composition. The group-based dietary intervention had a weight-reduction goal of ≥10%, and the exercise intervention consisted of a gradual escalation to 45-min aerobic exercise 5 day/week. Participants were predominantly non-Hispanic whites (85%) with a mean age of 58.0 ± 5.0 years, a mean BMI of 30.9 ± 4.0 kg/m(2) and an average of 47.8 ± 4.4% body fat. Baseline and 12-month weight and adiposity measures were obtained by staff blinded to participants' intervention assignment. Three hundred and ninety nine women completed the trial (91% retention). Using an intention-to-treat analysis, average weight loss at 12 months was -8.5% for the D group (P < 0.0001 vs. C), -2.4% for the E group (P = 0.03 vs. C), and -10.8% for the D+E group (P < 0.0001 vs. C), whereas the C group experienced a nonsignificant -0.8% decrease. BMI, waist circumference, and % body fat were also similarly reduced. Among postmenopausal women, lifestyle-change involving diet, exercise, or both combined over 1 year improves body weight and adiposity, with the greatest change arising from the combined intervention.     

A prospective study of breakfast consumption and weight gain among U.S. men

Objective: The aim was to investigate the association between breakfast consumption and long‐term weight gain in an adult male population. Research Methods and Procedures: We evaluated prospective data on 20,064 U.S men, 46 to 81 years of age, who participated in the Health Professionals Follow‐up Study. Data on body weight, dietary factors, and lifestyle variables were obtained by validated questionnaires. We examined weight gain during 10 years of follow‐up. Results: Overall, 5857 men had a weight gain of 5 kg or greater during 10 years of follow‐up. Breakfast consumption was inversely associated with the risk of 5‐kg weight gain after adjustment for age [hazard ratio (HR) = 0.77 (95% confidence interval [CI], 0.72 to 0.82)], and this association was independent of lifestyle and BMI at baseline [HR = 0.87 (95% CI, 0.82 to 0.93)]. Fiber and nutrient intakes partially explained the association between breakfast consumption and weight gain. The inverse association between breakfast consumption and weight gain was more pronounced in men with a baseline BMI of 25 kg/m² or lower [multivariate HR = 0.78 (95% CI, 0.70 to 0.87)] than in men who were overweight at baseline [HR = 0.92 (95% CI, 0.85 to 1.00)]. Furthermore, we observed that an increasing number of eating occasions in addition to three standard meals was associated with a higher risk of 5‐kg weight gain [HR = 1.15 (95% CI, 1.06 to 1.25, for ≥2 vs. 0 additional eating occasions)]. Discussion: These findings suggest that the consumption of breakfast may modestly contribute to the prevention of weight gain as compared with skipping breakfast in middle‐aged and older men.     

Teammates and social influence affect weight loss outcomes in a team-based weight loss competition

Team-based internet interventions are increasing in popularity as a way of promoting weight loss in large numbers of individuals. Given that social networks influence health behavior change, this study investigated the effects of teammates and social influence on individual weight loss during a team-based weight loss competition. Shape Up Rhode Island (SURI) 2009 was a 12-week online program open to adult residents of Rhode Island. Participants joined with a team and competed with other teams on weight loss and/or physical activity. Overweight/obese (OW/OB) individuals (N = 3,330; 76% female; age = 46.1 ± 10.8; BMI = 31.2 ± 5.3 kg/m(2)), representing 987 teams, completed the weight loss program. Multilevel modeling was used to examine whether weight loss clustered among teammates and whether percentage of teammates in the weight loss division and reported teammate influence on weight loss were associated with individual weight outcomes. OW/OB completers reported losing 4.2 ± 3.4% of initial body weight. Weight loss was similar among teammates (intraclass correlation coefficient (ICC) = 0.10, P < 0.001). Moreover, having a greater percentage of teammates in the weight loss division and reporting higher social influence for weight loss were associated with greater percent weight loss (P's ≤ 0.002). Similarly, achieving a clinically significant (5%) weight loss tended to cluster within teams (ICC = 0.09; P < 0.001) and having more teammates in the weight loss division and higher social influence for weight loss were associated with increased likelihood of achieving a 5% weight loss (odds ratio (OR) = 1.06; OR = 1.20, respectively). These results suggest that teammates affect weight loss outcomes during a team-based intervention. Harnessing and maximizing teammate influence for weight loss may enhance weight outcomes in large-scale team-based programs.     

Does Excess Pregnancy Weight Gain Constitute a Major Risk for Increasing Long‐term BMI?

Objective: The objective was to assess the relevance of the recommendations of the Institute of Medicine (IOM), regarding gestational weight gain (GWG) for long‐term BMI development. Research Methods and Procedures: The Stockholm Pregnancy and Women's Nutrition is a follow‐up study of 483 women who delivered children in 1984 to 1985. ANOVA was used to examine the change in body weight before pregnancy, at 6 months, and 1 year postpartum and 15 years after childbirth. Multiple linear regression was used to assess the predictors of BMI at 15‐year follow‐up. Results: The weight increase from baseline to 15‐year follow‐up was 6.2 kg for IOM‐insufficient, 6.7 kg for IOM‐recommended, and 10.0 kg for IOM‐excessive weight gain (p < 0.01). ANOVA showed a main effect of time, group and group by time interaction. The weight of the women who had excessive GWG was significantly greater at each time‐point of follow‐up than the weight of those who gained within or below recommendations. GWG was related to BMI at 15‐year follow‐up even after accounting for several confounders. Women who gained excessive weight during pregnancy had an increase of 0.72 kg/m² in long‐term BMI compared with women who gained within recommendations. Discussion: The findings support the adequateness of IOM guidelines, not only for the pregnancy‐related health matters, but also for preventing long‐term weight retention after delivery. Healthcare providers should give women appropriate advice for controlling GWG and motivate them to lose pregnancy‐related weight during postpartum to prevent future overweight.     

Effect of weight loss in adults on estimation of risk due to adiposity in a cohort study

The effect of overweight and obesity on the risk of fatal disease tends to attenuate with age. To evaluate whether this effect is partly attributable to disease-related weight loss, we examined the prebaseline history of weight loss and diseases associated with weight loss among adults enrolled in a cohort study. We conducted an analysis of 7,855 adult cohort members of the Adventist Health Study (AHS) I who had provided anthropometric data on surveys at baseline and 17 years prior to baseline. Among adults in the recommended range of BMI (19-25 kg/m(2)) at baseline we found that: (i) the prevalence of prebaseline weight loss of 5 kg/m(2) from an overweight or obese state was 20.4% and increased with age (12.6% for <65 years; 27.7% for 65-84 years; 36.7% for >85 years) and (ii) prebaseline weight loss of 5 kg/m(2) from an overweight or obese state was associated with diabetes (odds ratio (OR) = 2.91 95% confidence interval (CI) = (2.16, 3.93)), coronary heart disease (OR = 1.84 95% CI = (1.42, 2.40)), and high blood pressure (OR = 1.51 95% CI = (1.26, s1.82)). During 12 years of follow-up, we found evidence that hazard ratios for adiposity can be confounded by disease-related weight loss. Our findings raise the possibility that prebaseline weight loss can confound the estimation of risk due to adiposity at baseline in a cohort study.     

Effect of 3-year weight history on blood pressure: the atherosclerosis risk in communities study

The objective of this study was to examine the effect of weight history on blood pressure. Extant data from the Atherosclerosis Risk in Communities (ARIC) study were used to compare blood pressure in women (n=5,675) and men (n=4,893) with different 3-year weight histories, but similar current BMI. We used mixed models regression adjusted for ethnicity, age, education, field center, smoking, alcohol consumption, antihypertensive medications, interval length, and BMI at follow-up. We also examined associations between 3-year weight history and blood pressure within weight status categories (normal weight (>or=18.5 to <25.0 kg/m2), overweight (>or=25.0 to <30.0 kg/m2), and obese (>or=30.0 kg/m2)). We found weight history affected both systolic and diastolic blood pressures. Compared to men at the same BMI who had maintained their weight, men who had experienced a 10% weight gain over the previous 3 years had systolic and diastolic blood pressures that were 2.6 and 1.9 mm Hg higher, respectively (P<0.001 for both). Associations in women were in the same direction, but smaller at 0.9 and 0.6 mm Hg (P<0.001). With the exception of diastolic blood pressure in normal weight women, we found no significant interactions between weight change and current weight status. In conclusion, some of the variation in blood pressure among individuals at the same BMI may be due to weight change history. Effects of 3-year weight change history appear to be stronger and more consistent in men than in women, and generally similar regardless of current weight status.     

Maternal Obesity and Infant Heart Defects

Objective: This study determined whether obese women have an increased risk of cardiovascular defects in their offspring compared with average weight women. Research Methods and Procedures: In a case‐control study, prospectively collected information was obtained from Swedish medical health registers. The study included 6801 women who had infants with a cardiovascular defect and, as controls, all delivered women (N = 812, 457) during the study period (1992 to 2001). Infants with chromosomal anomalies or whose mothers had pre‐existing diabetes were excluded. Obesity was defined as BMI >29 kg/m², and morbid obesity was defined as BMI >35 kg/m². Comparisons were made with average weight women (BMI = 19.8 to 26 kg/m²). Results: In the group of obese mothers, there was an increased risk for cardiovascular defects compared with the average weight mothers [adjusted odds ratio (OR) = 1.18; 95% CI, 1.09 to 1.27], which was slightly more pronounced for the severe types of cardiovascular defects (adjusted OR = 1.23; 95% CI, 1.05 to 1.44). With morbid obesity, the OR for cardiovascular defects was 1.40 (95% CI, 1.22 to 1.64), and for severe cardiovascular defects, the OR was 1.69 (95% CI, 1.27 to 2.26). There was an increased risk for all specific defects studied among the obese women, but only ventricular septal defects and atrial septal defects reached statistical significance. Discussion: In this sample, a positive association was found between maternal obesity in early pregnancy and congenital heart defects in the offspring. A suggested explanation is undetected type 2 diabetes in early pregnancy, but other explanations may exist.     

Dietary adherence during weight loss predicts weight regain

This study examined the relationship between previous dietary adherence during a low-calorie diet weight loss intervention and subsequent weight change during a 2-year follow-up for weight maintenance. One hundred and sixteen healthy, recently weight reduced (lost ~12 kg, BMI 22-25 kg/m2) premenopausal women were studied. Dietary adherence was assessed by doubly labeled water (DLW) and body composition change. Comparisons were made between the upper and lower tertiles for previous dietary adherence and subsequent weight change at 1- and 2-year follow-up. Percent weight regained was significantly lower (30.9 ± 6.7% vs. 66.7 ± 9.4%; P < 0.05) in the upper compared to the lower adherence tertile for previous weight loss dietary adherence (49.9 ± 8.8% vs. 96.8 ± 12.8% P < 0.05) at 1- and 2-year follow-up, respectively. This difference was partly explained by increases in daily activity-related energy expenditure (AEE) (+95 ± 45 kcal/day vs. -44 ± 42 kcal/day, P < 0.05) and lower daily energy intake (2,066 ± 71 kcal/day vs. 2,289 ± 62 kcal/day, P < 0.05) in the higher tertile for previous dietary adherence, compared to the lower. These findings suggest that higher adherence (i.e., higher tertile) to the previous low-calorie diet predicts lower weight regain over 2-year follow-up for weight maintenance, which is explained by lower energy intake and higher physical activity. Finally, how well an individual adheres to a low-calorie diet intervention during weight loss may be a useful tool for identifying individuals who are particularly vulnerable to subsequent weight regain.