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.     

Prevalence of Sleep Apnea and Electrocardiographic Disturbances in Morbidly Obese Patients

Objective: To determine the prevalence of sleep apnea in morbidly obese patients and its relationship with cardiac arrhythmias. Research Methods and Procedures: Fifty‐two consecutive morbidly obese (body mass index ≥ 40 kg/m²) outpatients from the Obesity Clinic of the National Institute of Nutrition Salvador Zubirán underwent two nights of polysomnography with standard laboratory techniques. Electrocardiographic polysomnography signals (Lead II) were evaluated by two experienced cardiologists, and sleep complaints were measured with a standard sleep questionnaire (Sleep Disorders Questionnaire). In order to make comparisons between groups with different severities of sleep‐disordered breathing, we classified the patients in four groups using the apnea‐hypopnea index (AHI): Group 1, AHI 5 < 15 (n = 10); Group 2, AHI 15 < 30 (n = 10); Group 3, AHI 30 < 65 (n = 14); Group 4, AHI ≥ 65 (n = 17). Results: A wide range of sleep‐disordered breathing, ranging from AHI of 2.5 to 128.9 was found. Ninety‐eight percent of the sample (n = 51) had an AHI ≥ 5 (mean = 51 ± 37), and 33% had severe sleep apnea with AHI ≥ 65 with a mean nocturnal desaturation time of <65% over 135 minutes. Electrocardiographic abnormalities were present in 31% of the patients. Cardiac rhythm alterations showed an association with the level of sleep‐disordered breathing and oxygen desaturation. Discussion: We conclude that there is a high prevalence of sleep apnea in morbidly obese patients and that the risk for cardiac arrhythmias increases in this population in the presence of a severe sleep apnea (AHI ≥ 65) with severe oxygen desaturation (Sao ₂ ≤ 65%).     

The Effect of Weight Loss on Sleep‐disordered Breathing in Obese Teenagers

The objective of this study was to assess the effect of weight loss on sleep‐disordered breathing (SDB) in obese teenagers attending a residential treatment center. We also assessed whether the presence of SDB at the start of the weight management therapy was correlated with the amount of weight loss achieved. Obese teenagers were recruited and underwent anthropometry and sleep screening. Subjects with SDB (apnea hypopnea index (AHI) ≥ 2) received a follow‐up screening after weight loss therapy. Sixty‐one obese subjects were included (age = 14.8 ± 2.3; BMI z score = 2.7 ± 0.4). Thirty‐one subjects were diagnosed with SDB with 38% continuing to have residual SDB after a median weight loss of 24.0 kg. Subjects with SDB had a higher median relative decrease in BMI z score compared to subjects without SDB which was 30.5, 33.6, and 50.4% in the group with AHI of the baseline screening study < 2, 2 ≤ AHI < 5, and AHI ≥ 5, respectively (P = 0.02). AHI of the baseline screening study correlated significantly with the relative decrease in BMI z score (partial r = 0.37; P = 0.003), controlling for gender, age, initial BMI z score, and time between both studies. In conclusion, weight loss was successful in treating SDB in obese teenagers. In addition, there was a positive association between the severity of SDB at the start of the treatment and the amount of weight loss achieved. These findings are in favor of considering weight loss as a first‐line treatment for SDB in obese children and adolescents.     

Psychosocial predictors of 4‐year BMI change in overweight and obese children in primary care

Objective:

This study aimed to determine whether (( 1 ) ) initial and/or (( 2 ) ) changes in psychosocial functioning predict body mass index (BMI) z‐score change over 4 years in overweight/mildly obese 5‐ to 9‐year old children presenting to primary care.

Design and Methods:

Eligible participants (n = 258) were overweight/mildly obese children (IOTF criteria) recruited into the LEAP2 trial (ISRCTN52511065) from 3,958 children visiting general practitioners in Melbourne, Australia from May 2005 to July 2006. Predictors were change scores calculated from repeated measures of parent‐ and child‐reported child health‐related quality of life (PedsQL) and self‐esteem; child‐reported desire to be thinner; and parent‐reported child weight concern. Outcome was measured BMI z‐score change from baseline to 4 years.

Results:

The 189 respondents (61% female; 73% retention) showed little mean change in BMI z‐score (?0.08) but wide variation (standard deviation 0.50, range ?1.32 to 1.20). Only one baseline measure (better parent‐reported PedsQL School Functioning) predicted improving BMI z‐score. However, parents and children consistently reported that changes in psychosocial functioning (i.e., PedsQL Social and Global Self‐esteem) were inversely related to BMI z‐score change scores. The strongest predictors of decreases in BMI z‐scores were changes in child‐reported body‐image variables, i.e., improvements in Physical Appearance Self‐esteem (β =0.40, 95% CI ?0.98 to ?0.15, P < 0.01) and declines in Desire to be Thinner (β = 0.33, 95% CI 0.04 to 0.23, P < 0.01).

Conclusions:

At presentation to primary care, it seems unlikely that targeting the psychosocial factors measured in this study would influence BMI z‐score change in overweight/mildly obese children. Subsequent change in psychosocial well‐being covaries with BMI z‐score change and may have important adolescent ramifications; the causal directions for these associations require further research.

     

Parental obesity moderates the relationship between childhood appetitive traits and weight

Objective:

In this study, the independent and combined associations between childhood appetitive traits and parental obesity on weight gain from 0 to 24 months and body mass index (BMI) z‐score at 24 months in a diverse community‐based sample of dual parent families (n = 213) were examined.

Design and Methods:

Participants were mothers who had recently completed a randomized trial of weight loss for overweight/obese postpartum women. As measures of childhood appetitive traits, mothers completed subscales of the Children's Eating Behavior Questionnaire, including Desire to Drink (DD), Enjoyment of Food (EF), and Satiety Responsiveness (SR), and a 24‐h dietary recall for their child. Heights and weights were measured for all children and mothers and self‐reported for mothers' partners. The relationship between children's appetitive traits and parental obesity on toddler weight gain and BMI z‐score were evaluated using multivariate linear regression models, controlling for a number of potential confounders.

Results:

Having two obese parents was related to greater weight gain from birth to 24 months independent of childhood appetitive traits, and although significant associations were found between appetitive traits (DD and SR) and child BMI z‐score at 24 months, these associations were observed only among children who had two obese parents. When both parents were obese, increasing DD and decreasing SR were associated with a higher BMI z‐score.

Conclusions:

The results highlight the importance of considering familial risk factors when examining the relationship between childhood appetitive traits on childhood obesity.     

Ability to taste 6-n-propylthiouracil and BMI in low-income preschool-aged children

Background: Sensitivity to the bitter compound 6‐n‐propylthiouracil (PROP) is genetically mediated. Sensitivity to PROP has been associated with weight status in both adults and children. Objective: To determine whether there is an association between PROP sensitivity and BMI in low‐income children of diverse race/ethnicity, among whom there is a high prevalence of obesity. Methods and Procedures: Eighty‐one preschool‐aged children attending Head Start tasted a solution of 560 μmol/l PROP and reported whether it tasted “like water” or “like something else”. Mothers reported child's race, age, maternal education, maternal weight and height, child's reluctance to sample new foods via the Food Neophobia Scale (FNS), and child's dietary intake using a food frequency questionnaire. Child weight and height were measured. BMI was calculated and for children, expressed in z‐scores. Regression analyses were used to evaluate the relationship between child's PROP taster status and BMI z‐score, testing covariates child's age, gender, race, maternal education and BMI, and child's FNS score. Children's dietary intake was compared by PROP taster status. Results: PROP tasters, compared with nontasters, had significantly higher BMI z‐scores (0.99 (s.d. 1.24) vs. 0.03 (1.12), P = 0.004) and had a significantly higher prevalence of overweight (31.8% vs. 5.6%, P = 0.025), but demonstrated no differences in reported dietary intake. The most parsimonious model predicting the child's BMI z‐score included only maternal BMI and the child's PROP taster status (R ² = 22.3%). Discussion: A genetically mediated ability to taste bitter may contribute to obesity risk in low‐income, preschool‐aged children.     

Quality of life in Mexican-American children following a weight management program

Objective: The objective was to evaluate quality of life (QOL) in at‐risk‐for‐overweight and overweight Mexican‐American children after participating in 6 months of intensive weight management or self‐help. Research Methods and Procedures: Eighty sixth‐ and seventh‐grade at‐risk‐for‐overweight (BMI ≥85th to <95th percentile) and overweight (BMI ≥95th percentile) Mexican‐American children were randomly assigned to either intensive instructor‐led intervention (ILI) or self‐help (SH). The ILI condition included daily participation for 12 weeks in a school‐based program comprised of nutrition education, physical activity, and behavior modification, followed by ongoing monthly maintenance. QOL was assessed at baseline and 6 months via child self‐report PedsQL. QOL outcomes were compared across treatment groups, and the impact of change in zBMI on change in QOL was evaluated. Results: Children in the ILI condition not only achieved significantly greater weight loss (zBMI, ?0.13 ± 0.14; p < 0.001) but also significantly greater physical QOL improvements than those in the SH condition at 6 months (p < 0.05). Furthermore, physical QOL increases were associated with zBMI reduction (p < 0.05). However, neither psychosocial nor total QOL was significantly impacted by intervention or zBMI change. Discussion: These findings show that even modest decreases in zBMI after weight management result in improved physical QOL in Mexican‐American children. These results illustrate the clear need to include evaluation of QOL in the process of identifying effective weight management programs.     

Effects of a School‐based Weight Maintenance Program for Mexican‐American Children: Results at 2 Years

The prevalence of childhood overweight has increased significantly, with the highest rates noted among Mexican Americans. Many negative health outcomes are associated with overweight; thus, there is a need for effective weight‐loss interventions tailored to this group. This study evaluated 24‐month outcomes of a randomized, controlled trial involving an intensive lifestyle‐based weight maintenance program targeting overweight Mexican‐American children at a charter school in Houston, Texas. A total of 60 children (33 males, 55%) between the ages of 10 and 14 at or >85th percentile for BMI were recruited. Participants were randomized to an instructor‐led intervention (ILI) or a self‐help (SH) program, both aimed at modifying eating and physical activity behaviors using behavior modification strategies. Changes in participants' standardized BMI (zBMI) were assessed at baseline, 1, and 2 years. Tricep skinfold, total cholesterol, triglycerides, high‐density lipoprotein cholesterol, and calculated low‐density lipoprotein were assessed at baseline and 1 year. ILI participants showed significantly greater decreases in zBMI at 1 and 2 years (F = 26.8, P < 0.001, F = 4.1, P < 0.05, respectively) compared to SH controls. ILI participants showed greater improvements in body composition, as measured by tricep skinfold (F = 9.75, P < 0.01). Children in the ILI condition experienced benefits with respect to total cholesterol (F = 7.19, P < 0.05) and triglycerides (F = 4.35, P < 0.05) compared to children in the SH condition. Overall, the school‐based intervention resulted in improved weight and clinical outcomes in overweight Mexican‐American children, and zBMI was maintained over 2 years.     

A community intervention reduces BMI z-score in children: Shape Up Somerville first year results

Objective: The objective was to test the hypothesis that a community‐based environmental change intervention could prevent weight gain in young children (7.6 ± 1.0 years). Research Methods and Procedures: A non‐randomized controlled trial was conducted in three culturally diverse urban cities in Massachusetts. Somerville was the intervention community; two socio‐demographically‐matched cities were control communities. Children (n = 1178) in grades 1 to 3 attending public elementary schools participated in an intervention designed to bring the energy equation into balance by increasing physical activity options and availability of healthful foods within the before‐, during‐, after‐school, home, and community environments. Many groups and individuals within the community (including children, parents, teachers, school food service providers, city departments, policy makers, healthcare providers, before‐ and after‐school programs, restaurants, and the media) were engaged in the intervention. The main outcome measure was change in BMI z‐score. Results: At baseline, 44% (n = 385), 36% (n = 561), and 43% (n = 232) of children were above the 85th percentile for BMI z‐score in the intervention and the two control communities, respectively. In the intervention community, BMI z‐score decreased by ?0.1005 (p = 0.001, 95% confidence interval, ?0.1151 to ?0.0859) compared with children in the control communities after controlling for baseline covariates. Discussion: A community‐based environmental change intervention decreased BMI z‐score in children at high risk for obesity. These results are significant given the obesigenic environmental backdrop against which the intervention occurred. This model demonstrates promise for communities throughout the country confronted with escalating childhood obesity rates.     

Two‐Year Changes in Child Weight Status,Diet, and Activity by Neighborhood Nutrition and Physical Activity Environment

Objective

The aim of this study was to examine 2‐year changes in weight status and behaviors among children living in neighborhoods differing on nutrition and activity environments.

Methods

A prospective observational study, the Neighborhood Impact on Kids study, was conducted in King County, Washington, and San Diego County, California. Children 6 to 12 years old and a parent or caregiver completed Time 1 (n = 681) and Time 2 (n = 618) assessments. Children lived in neighborhoods characterized as “high/favorable” or “low/unfavorable” in nutrition and activity environments, respectively (four neighborhood types). Child BMI z score and overweight or obesity status were primary outcomes, with diet and activity behaviors as behavioral outcomes.

Results

After adjusting for sociodemographics and Time 1 values, children living in two of the three less environmentally supportive neighborhoods had significantly less favorable BMI z score changes (+0.11, 95% CI: 0.01‐0.21; + 0.12, 95% CI: 0.03‐0.21), and all three less supportive neighborhoods had higher overweight or obesity (relative risks, 1.41‐1.49; 95% CI: 1.13‐1.80) compared with children in the most environmentally supportive neighborhoods. Changes in daily energy intake and sedentary behavior by neighborhood type were consistent with observed weight status changes, with unexpected findings for physical activity.

Conclusions

More walkable and recreation‐supportive environments with better nutrition access were associated with better child weight outcomes and related behavior changes.     

Parental recognition of overweight in school-age children

Objective: Examine the accuracy of parental weight perceptions of overweight children before and after the implementation of childhood obesity legislation that included BMI screening and feedback. Methods and Procedures: Statewide telephone surveys of parents of overweight (BMI ≥ 85th percentile) Arkansas public school children before (n = 1,551; 15% African American) and after (n = 2,508; 15% African American) policy implementation were examined for correspondence between parental perception of child's weight and objective classification. Results: Most (60%) parents of overweight children underestimated weight at baseline. Parents of younger children were significantly more likely to underestimate (65%) than parents of adolescents (51%). Overweight parents were not more likely to underestimate, nor was inaccuracy associated with parental education or socioeconomic status. African‐American parents were twice as likely to underestimate as whites. One year after BMI screening and feedback was implemented, the accuracy of classification of overweight children improved (53% underestimation). African‐American parents had significantly greater improvements than white parents (P < 0.0001). Discussion: Parental recognition of childhood overweight may be improved with BMI screening and feedback, and African‐American parents may specifically benefit. Nonetheless, underestimation of overweight is common and may have implications for public health interventions.     

Body mass effects of a physical activity and healthy food intervention in middle schools

Objective: To evaluate the effects of a 2‐year middle school physical activity and healthy food intervention, including an environmental and computer‐tailored component on BMI and BMI z‐score in boys and girls. Research Methods and Procedures: A random sample of 15 schools with seventh and eighth graders was randomly assigned to three conditions: an intervention with parental support group, an intervention‐alone group, and a control group. Weight and height were measured at the beginning and end of each school year to assess BMI and BMI z‐score. A physical activity and healthy food program was implemented over 2 school years. Results: In girls, BMI and BMI z‐score increased significantly less in the intervention with parental support group compared with the control group (p < 0.05) or the intervention‐alone group (p = 0.05). In boys, no significant positive intervention effects were found. Discussion: This was the first study evaluating the effectiveness of an intervention combining environmental changes with personal computer‐tailored feedback on BMI and BMI z‐score in middle school children. After 2 school years, BMI and BMI z‐score changed in a more positive direction in girls as a result of the intervention with parental support.     

The association between an objective measure of physical activity and weight status in preschoolers

Objective: Our objective was to determine the association between physical activity and BMI among racially diverse low‐income preschoolers. Research Methods and Procedures: This was a cross‐sectional study of 2‐ to 5‐year‐olds (n = 56) enrolled in Massachusetts Special Supplemental Nutrition Program for Women, Infants & Children (WIC). Physical activity was measured for 7 consecutive days with an accelerometer. Height and weight were obtained from WIC records, and BMI‐for‐age percentiles were calculated based on the Centers for Disease Control and Prevention's (CDC) 2000 Growth Charts. At‐risk‐for‐overweight (BMI‐for‐age of ≥85th to <95th percentile) and overweight (BMI‐for‐age ≥95th percentile) groups were combined and referred to as overweight. Final analysis inclusion criteria were: completion of 4.5 days of activity assessment and anthropometric data obtained within 90 and 120 days of the activity assessment for children ages 24 to 35.99 and 36 to 59.99 months, respectively. Results: Overweight children had significantly lower mean daily very vigorous minutes (VVM) (2.6 mins vs. 4.6 mins, p < 0.05) and lower very active minutes (VAM) [i.e., sum of vigorous minutes (VM) and VVM] per day (22.9 mins vs. 32.1 mins, p < 0.05) than children who were not overweight. Daily VVM [odds ratio (OR) = 0.68; 95% confidence interval (CI), 0.49 to 0.96], VM (OR = 0.94; CI, 0.88 to 1.00), and VAM (OR = 0.94; 95% CI, 0.89 to 1.00) were all associated with significantly lower odds of being overweight. Discussion: This study suggests that, in a diverse group of preschoolers, vigorous and very vigorous activity are associated with lower odds of overweight. However, these findings require corroboration in a diverse sample of preschoolers using a longitudinal design.     

The association between self‐reported sleep quality and overweight in a Chinese population

Objective:

Sleep quality and obesity are associated with type 2 diabetes, hypertension, and metabolic syndrome. However, there is limited research on the association between sleep quality and obesity, and thus the aim of this study is to investigate this relationship in a Chinese population.

Design and Methods:

Subjects were recruited from the Prevention Health Center of National Cheng Kung University Hospital. Anthropometric data and metabolic parameters were measured. Being overweight or obese was defined according to the recommendations of the Department of Health in Taiwan. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI).

Results:

Of the total 2,803 subjects, 1,059 were classified as normal weight, 1,127 were overweight, and 617 were obese. The global PSQI score were 6.30 ± 2.56, 6.61 ± 2.96, and 7.02 ± 2.95 in subjects who were normal weight, overweight, and obese, respectively (test for trend, P < 0.001). Of the variables tested in the multivariate linear regression model, female gender, being overweight, obesity, sleep duration, and alcohol drinking were significantly associated with global PSQI scores, and in the multivariate logistic regression model, female gender, being overweight, obesity, and sleep duration were independent predictors of poor sleepers after controlling for age, gender, BMI or different weight statuses, sleep duration, alcohol drinking, smoking, habitual exercise, hypertension, newly diagnosed diabetes, total cholesterol, high‐density lipoprotein, triglyceride, estimated glomerular filtration rate, and alanine aminotransferase.

Conclusions:

In conclusion, female gender, being overweight, obesity, and sleep duration were associated with poor sleep quality independent of cardiometabolic risk factors. In clinical practice, subjects who are obese, or even only overweight, should be evaluated for the presence of sleep disturbance.     

Sleep habits of Iranian pre-school children in an urban area: Late sleeping and sleep debt in children

Using BEARS (Bedtime problems, Excessive sleepiness, Awakenings during the night, Regularity of sleep, Snoring), and CSHQ (Children’s Sleep Habits Questionnaires) screening tools with 224 participants revealed that Iranian children have shorter night sleep duration than expected (9.54 vs 12 h) for their age group. Earlier sleepers had longer night sleep duration (10:36 ± 1:12; 9:12 ± 1:06 h, P > 0.001), and total daily sleep time (11:36 ± 1:42; 10:36 ± 1:30 h, P = 0.005) than late sleepers. A majority (85%) of naptakers had sleep bedtime of 22:00 or later. The poor sleep quality of Iranian preschool children is probably due to cultural characteristics, climate differences, or harmful sleep habits.

     

Differences in Overweight and Obesity among Children from Migrant and Native Origin: The Role of Physical Activity,Dietary Intake,and Sleep Duration

A cross-sectional survey was performed to examine to what degree differences in overweight and obesity between native Dutch and migrant primary school children could be explained by differences in physical activity, dietary intake, and sleep duration among these children. Subjects (n=1943) were primary school children around the age of 8–9 years old and their primary caregivers: native Dutch children (n=1546), Turkish children (n=93), Moroccan children (n=66), other non-western children (n=105), and other western children (n=133). Multivariate regressions and logistic regressions were used to examine the relationship between migrant status, child’s behavior, and BMI or prevalence of overweight, including obesity (logistic). Main explanatory variables were physical activity, dietary intake, and sleep duration. We controlled for age, sex, parental educational level, and parental BMI. Although sleep duration, dietary intake of fruit, and dietary intake of energy-dense snacks were associated with BMI, ethnic differences in sleep duration and dietary intake did not have a large impact on ethnic differences in overweight and obesity among children from migrant and native origin. It is suggested that future preventive strategies to reduce overweight and obesity, in general, consider the role of sleep duration. Also, cross-cultural variation in preparation of food among specific migrant groups, focusing on fat, sugar, and salt, deserves more attention. In order to examine which other variables may clarify ethnic differences in overweight and obesity, future research is needed.     

Risk Factors for Adult Overweight and Obesity in the Quebec Family Study: Have We Been Barking Up the Wrong Tree?

The aim of this study was to determine the independent contribution of previously reported risk factors for adult overweight and obesity. A cross‐sectional (n = 537) and a longitudinal (n = 283; 6‐year follow‐up period) analysis was performed for nine risk factors for overweight and obesity assessed in adult participants (aged 18–64 years) of the Quebec Family Study (QFS). The main outcome measure was overweight/obesity, defined as a BMI ≥25 kg/m². Using logistic regression analysis adjusted for age, sex, and socioeconomic status, short sleep duration, high disinhibition eating behavior, low dietary calcium intake, high susceptibility to hunger behavior, nonparticipation in high‐intensity physical exercise, high dietary restraint behavior, nonconsumption of multivitamin and dietary supplements, high dietary lipid intake, and high alcohol intake were all significantly associated with overweight and obesity in the cross‐sectional sample. The analysis of covariance adjusted for age, socioeconomic status, and all other risk factors revealed that only individuals characterized by short sleep duration, high disinhibition eating behavior, and low dietary calcium intake had significantly higher BMI compared to the reference category in both sexes. Over the 6‐year follow‐up period, short‐duration sleepers, low calcium consumers, and those with a high disinhibition and restraint eating behavior score were significantly more likely to gain weight and develop obesity. These results show that excess body weight or weight gain results from a number of obesogenic behaviors that have received considerable attention over the past decade. They also indicate that the four factors, which have the best predictive potential of variations in BMI, be it in a cross‐sectional or a longitudinal analytical design, do not have a “caloric value” per se.     

Moderate exercise and bright light treatment in overweight and obese individuals

Objective: Increased physical activity is important given the concern over the growing rates of obesity. The aim of this study is to conduct a controlled investigation of the effects of bright light therapy and exercise on weight loss and body composition in overweight and obese individuals. Research Methods and Procedures: Twenty‐five overweight and obese subjects were assigned to 6 weeks of moderate exercise with or without bright light treatment. Outcome measure included changes in body mass and body composition and ratings of mood, seasonality, and sleep. Results: Body weight decreased significantly with exercise in subjects in the light and non‐light treatment groups, but the change was not significantly different between the groups. Similar results were found for BMI. With exercise, body fat decreased significantly only in the light treatment group. There was a significant effect of the interaction of group by time on body fat composition, but the group by time interaction failed to reach statistical significance for body weight and BMI. Mood scores improved significantly with exercise in the light group, but no significant changes were noted regarding sleep. Discussion: This preliminary study is the first to show that addition of bright light treatment to a 6‐week moderate exercise program can alter body composition by significantly reducing body fat. The reduction in body fat mass is of particular importance, because visceral fat has been particularly implicated as a major factor in the development of the metabolic syndrome. This study is an important step toward finding ways to maximize the effects of exercise.     

The flow-mediated dilation response to acute exercise in overweight active and inactive men

Objective: Inflammation has been found to play a role in the etiology of cardiovascular disease as well as provoke endothelial dysfunction. Inflammatory cytokines associated with endothelial function are interleukin‐6 (IL‐6) and tumor necrosis factor‐α (TNF‐α). IL‐6 is exercise intensity dependent and has been shown to inhibit TNF‐α expression directly. The aim of this study was to investigate the interaction of IL‐6 and TNF‐α on endothelial function in response to acute exercise in overweight men exhibiting different physical activity profiles. Methods and Procedures: Using a randomized mixed factorial design, 16 overweight men (8 active, maximal exercise capacity (VO₂peak) = 34.2 ± 1.7, BMI = 27.4 ± 0.7 and 8 inactive, VO₂peak = 30.9 ± 1.2, BMI = 29.3 ± 1.0) performed three different intensity acute exercise treatments. Brachial artery flow‐mediated dilation (FMD) and subsequent blood samples were taken pre‐exercise and 1 h following the cessation of exercise. Results: Independent of exercise intensity, the active group displayed a 24% increase (P = 0.034) in FMD following acute exercise compared to a 32% decrease (P = 0.010) in the inactive group. Elevated (P < 0.001) concentrations of IL‐6 following moderate (50% VO₂) and high (75% VO₂) intensity acute exercise were observed in both groups; however, concentrations of TNF‐ α were unchanged in response to acute exercise (P = 0.584). Discussion: The FMD response to acute exercise is enhanced in active men who are overweight, whereas inactive men who are overweight exhibit an attenuated response. The interaction of IL‐6 and TNF‐ α did not provide insight into the physiological mechanisms associated with the disparity of FMD observed between groups.     

RETRACTION: C-reactive Protein and Metabolic Syndrome in Youth: A Strong Relationship?

Retraction: Note from the Editor‐in‐Chief: This paper is retracted Objective: Metabolic syndrome (MS) is on the rise in youth. As high‐sensitivity C‐reactive protein (hs‐CRP) is associated with cardiovascular/metabolic disorders, we evaluated the association between MS and its components and hs‐CRP in a sample of Brazilian overweight and obese youth. Methods and Procedures: A total of 407 students (229 girls, 273 with excessive weight, 11.3 ± 3.2 years) were evaluated. Measurement included BMI, waist circumference (WC), blood pressure, lipids, insulin, and hs‐CRP. Excessive weight was defined using BMI z ‐score; MS by the modified National Cholesterol Education Program—Adult Treatment Panel III. Results: Subjects were classified into two groups: with MS (n = 72) and without (n = 335). hs‐CRP means and medians were higher in MS group (1.41 mg/l vs. 1.06 mg/l, P < 0.001; 2.21 mg/l vs. 1.23 mg/l, P < 0.001). Associations between hs‐CRP quartiles and insulin resistance (IR) (P < 0.001), MS (P < 0.001), WC (P < 0.000), BMI z‐score (P < 0.001), hypertension (P < 0.001), hypertriglyceridemia (P < 0.001), and low HDL‐c (P = 0.023) were significant; adjustment of hs‐CRP for BMI z‐score eliminated the previous association, except for the number of MS components (nMSc) (P < 0.001). Adjusting for homeostasis model assessment method of IR (HOMA‐IR) did not eliminate the relation between hs‐CRP and MS components. Furthermore, increases in BMI z ‐score and nMSc were associated with an increased hs‐CRP. Excessive weight (odds ratio (OR), 7.9; confidence interval (CI), 4.7–13.4; P = 0.000), hypertension (OR, 2.3; CI, 1.3–4.2; P = 0.003), and hypertriglyceridemia (OR, 2.3; CI, 1.5–3.7; P < 0.001) were independently associated with hs‐CRP. Discussion: In youth, hs‐CRP is strongly related with MS and its components, and is also determined by the body composition. This association indicates a precocious proinflammatory state.