Randomized Trial of a Lifestyle Program in Obese Infertile Women.

BACKGROUND: Small lifestyle-intervention studies suggest that modest weight loss increases the chance of conception and may improve perinatal outcomes, but large randomized, controlled trials are lacking. METHODS: We randomly assigned infertile women with a body-mass index (the weight in kilograms divided by the square of the height in meters) of 29 or higher to a 6-month lifestyle intervention preceding treatment for infertility or to prompt treatment for infertility. The primary outcome was the vaginal birth of a healthy singleton at term within 24 months after randomization. RESULTS: We assigned women who did not conceive naturally to one of two treatment strategies: 290 women were assigned to a 6-month lifestyle-intervention program preceding 18 months of infertility treatment (intervention group) and 287 were assigned to prompt infertility treatment for 24 months (control group). A total of 3 women withdrew consent, so 289 women in the intervention group and 285 women in the control group were included in the analysis. The discontinuation rate in the intervention group was 21.8%. In intention-to-treat analyses, the mean weight loss was 4.4 kg in the intervention group and 1.1 kg in the control group (P<0.001). The primary outcome occurred in 27.1% of the women in the intervention group and 35.2% of those in the control group (rate ratio in the intervention group, 0.77; 95% confidence interval, 0.60 to 0.99). CONCLUSIONS: In obese infertile women, a lifestyle intervention preceding infertility treatment, as compared with prompt infertility treatment, did not result in higher rates of a vaginal birth of a healthy singleton at term within 24 months after randomization. (Funded by the Netherlands Organization for Health Research and Development; Netherlands Trial Register number, NTR1530.).

Independent and combined effects of physical activity and body mass index on the development of Type 2 Diabetes - a meta-analysis of 9 prospective cohort studies.

BACKGROUND: The aim of this harmonized meta-analysis was to examine the independent and combined effects of physical activity and BMI on the incidence of type 2 diabetes. METHODS: Our systematic literature review in 2011 identified 127 potentially relevant prospective studies of which 9 fulfilled the inclusion criteria (total N = 117,878, 56.2 % female, mean age = 50.0 years, range = 25-65 years). Measures of baseline physical activity (low, intermediate, high), BMI-category [BMI < 18.4 (underweight), 18.5-24.9 (normal weight), 25.0-29.9 (overweight), 30+ (obese)] and incident type 2 diabetes were harmonized across studies. The associations between physical activity, BMI and incident type 2 diabetes were analyzed using Cox regression with a standardized analysis protocol including adjustments for age, gender, educational level, and smoking. Hazard ratios from individual studies were combined in a random-effects meta-analysis. RESULTS: Mean follow-up time was 9.1 years. A total of 11,237 incident type 2 diabetes cases were recorded. In mutually adjusted models, being overweight or obese (compared with normal weight) and having low physical activity (compared with high physical activity) were associated with an increased risk of incident type 2 diabetes (hazard ratios 2.33, 95 % CI 1.95-2.78; 6.10, 95 % CI: 4.63-8.04, and 1.23, 95 % CI: 1.09-1.39, respectively). Individuals who were both obese and had low physical activity had 7.4-fold (95 % CI 3.47-15.89) increased risk of type 2 diabetes compared with normal weight, high physically active participants. CONCLUSIONS: This harmonized meta-analysis shows the importance of maintaining a healthy weight and being physically active in diabetes prevention.

Psychological distress as a determinant of changes in body mass index over a period of 10years.

OBJECTIVE: To examine the longitudinal relationship between psychological distress and body mass index (BMI) changes over a period of five and ten years. METHOD: Data were used from the Dutch, prospective, population based Doetinchem Cohort study over the period 1995/1999 until 2005/2009 (N=5504). Psychological distress was assessed using the Mental Health Inventory (MHI-5). BMI (kg/m(2)) was calculated from measured body height and body weight. GEE analyses were used to examine the relationship between psychological distress at baseline and BMI change, and the development of overweight over five years. Linear and logistic regression analyses were used to examine these relations over ten years. RESULTS: Psychological distress predicted an extra overall increase in BMI of 0.14kg/m(2) (95% CI 0.03-0.25) over five years and an increase of 0.18kg/m(2) (95% CI 0.01-0.35) over ten years, when comparing psychologically distressed participants to psychologically healthy participants. This was especially the case among persons with normal weight (five years; B=0.26kg/m(2), 95% CI=0.12-0.40/ten years; B=0.32kg/m(2) 95% CI=0.11-0.53) and moderate overweight (five years: B=0.18kg/m(2), 95% CI=0.02-0.35) at baseline. Psychological distress did not predict the development of overweight five and ten years later. CONCLUSION: The results in this study indicated that psychological distress predicted an increased risk in gaining weight, but did not result in an increased risk for developing overweight.

Food supply and actions to improve dietary behaviour of students - a comparison between secondary schools participating or not participating in the 'Healthy School Canteen Program'.

OBJECTIVE: (i) To identify determinants of participation in the 'Healthy School Canteen Program', a programme that encourages schools to set up their canteen in a way that promotes healthy dietary behaviour. (ii) To compare food supply and actions between participating and non-participating schools. (iii) To investigate what reasons schools have to increase attention for nutrition in the curriculum. DESIGN: A cross-sectional study based on information from questionnaires performed in 2010/2011. SETTING: All secondary schools (age group 12-18 years) in the Netherlands (n 1145). SUBJECTS: Response was 33 % (n 375). Analyses included all schools with a canteen in which food is offered (28 %, n 325). RESULTS: None of the investigated determinants was associated with participation. Participating schools offered significantly (P < 0·001) more of eleven inventoried healthy foods (e.g. sandwiches, (butter)milk, fruit, light soft drinks, yoghurt and salad) than non-participating schools. However, there was no difference in the number of less healthy products offered (e.g. candy bars, cakes and regular soft drinks). Participating schools reported more often that they took actions to improve dietary behaviour and more often had a policy on nutrition. Participating schools more often increased attention for nutrition in the curriculum in recent years than non-participating schools (57 % v. 43 %, P = 0·01). Reported reasons were similar and included media attention, eating behaviour of students and 'overweight'. CONCLUSIONS: Schools that participate in the programme seemed to offer more healthy products in their canteens and took more actions to improve dietary behaviour than non-participating schools. However, at all schools less healthy foods were also available.

Differences in weight loss across different BMI classes: a meta-analysis of the effects of interventions with diet and exercise.

BACKGROUND: Lifestyle interventions are effective for weight loss and are recommended for persons with a body mass index (BMI) of 25-40 kg m(-2). However, this group is very heterogeneous, which could influence outcomes from lifestyle interventions. PURPOSE: In this systematic review, differences in 1-year weight change and percentage weight change after lifestyle interventions were investigated for participants varying in initial BMI using meta-analyses. METHOD: Twenty-two interventions with healthy Caucasian adults, a mean BMI between 25 and 40 kg m(-2), a dietary as well as a physical activity component aiming at weight loss, and at least five contact sessions guided by a professional health care provider were selected from a systematic search in the MEDLINE database. Participants in each intervention were divided into one of the three BMI classes: overweight (BMI of 25-29.99 kg m(-2)), class-I obesity (BMI of 30-34.99 kg m(-2)), and class-II obesity (BMI of 35-39.99 kg m(-2)). Differences in weight change and percentage weight change were analyzed and compared among different BMI classes within the same intervention by calculating standardized mean differences. RESULTS: Overweight participants lost 1.1 kg less (p < 0.01) than participants with class-I obesity and 1.5 kg less (p < 0.01) than participants with class-II obesity. For percentage weight change, no significant differences were found among the BMI classes. CONCLUSION: Average weight change during lifestyle interventions only differs to a small extent among people with BMI between 25 and 40 kg m(-2). This implies that these interventions are equally appropriate for these BMI classes.

Changes in weight and health-related quality of life. The Doetinchem Cohort Study.

BACKGROUND: The cross-sectional association between obesity and a lower health-related quality of life (HRQL) is clear. However, less is known about the association between changes in weight and HRQL. We examined the association between weight changes and changes in HRQL in a population-based sample of 2005 men and 2130 women aged 26-70 years. METHODS: Weight was measured two or three times with 5-year intervals between 1995 and 2009, and was categorised as stable (change ≤2 kg, 40%), weight loss (19%), or weight gain 2.1-4.0 kg, 4.1-6.0 kg, or >6 kg (41%). Changes in HRQL (SF36 questionnaire, including physical and mental scales) per weight change category were compared with a stable weight using generalised estimating equations. RESULTS: Weight gain was associated with declines of up to 5 points on five mainly physical scales and holds for different age categories. Especially for women, a dose-response relationship was observed, that is, larger weight gain was associated with larger declines in HRQL. Changes in HRQL for those with weight loss were small, but particularly on the mental scales, changes were in the negative direction compared to a stable weight. CONCLUSIONS: Weight gain and weight loss were associated with unfavourable changes in HRQL compared with a stable weight. For weight gain, this was most pronounced on the physical scales and for weight loss, although less consistent, on the mental scales.

The association between adverse life events and body weight change: results of a prospective cohort study.

BACKGROUND: Stress has been shown to be a determinant of weight change and risk for obesity. To date, there is scarce evidence that stressful life events and their severity contribute to changes in body weight. We studied the association between the occurrence, impact of and adaptation to adverse life events and weight change and the role of initial weight status. METHODS: Analyses were based on data from a population-based cohort of 2789 adults. Adverse life events, their impact and adaptation were measured retrospectively after baseline and follow-up weight and height measurements. RESULTS: Over six years, participants gained an average of 2.8 kg. There were no differences in weight change between those who had experienced an adverse life event versus those who had not. However, the impact of life events had a significant interaction with initial weight status. Adults with a healthy weight showed an average weight reduction of 0.2 kg (95% CIs: -0.7 - 0.2), and overweight adults showed an average weight gain of 0.4 kg (95% CIs: -0.3 - 1.1) for each point increase in impact after experiencing an adverse life event. Further, a slower adaptation to events was significantly associated with greater weight loss among those who lost weight. CONCLUSIONS: We found no proof for an association between life events and weight change in the entire study sample, but we found that adults at a healthy weight responded differently to adverse life events than those who were overweight.

The association between body mass index status and sick leave and the role of emotional exhaustion-a mediation analysis among a representative sample of dutch employees.

OBJECTIVE: To investigate the associations between body mass index (BMI) and sick leave, and the mediating role of emotional exhaustion. METHODS: Data were collected from a large survey among Dutch employees (n = 35,022). The causal pathway approach consisting of four regression analyses was applied. RESULTS: In women, moderate overweight and obesity were associated with higher sick leave; in men, obesity, but not moderate overweight, was associated with higher sick leave. Obese workers were at increased risk for emotional exhaustion. Emotional exhaustion was also associated with higher sick leave rates. Adjustment for emotional exhaustion in the association between BMI and sick leave hardly changed the effect size and significance remained. CONCLUSIONS: The association between BMI status and sick leave can be explained partially by the presence of emotional exhaustion. Workplace health promotion initiatives should take this into account.

Changes in school environment, awareness and actions regarding overweight prevention among Dutch secondary schools between 2006-2007 and 2010-2011.

BACKGROUND: Schools can be an important setting for the prevention of overweight. This nation-wide survey investigated changes in the obesogenity of the school environment, the awareness of schools regarding overweight, school health policy, and actions taken by schools to prevent overweight. METHODS: In 2006/2007 and 2010/2011, questionnaires were sent to all Dutch secondary schools, (n = 1250 and n = 1145, response rate 44% and 33% respectively, repeated data for 187 schools). RESULTS: The percentage of schools with vending machines for soft drinks (~90%) and sweets (~80%) remained fairly stable, whereas slightly more schools indicated to have a canteen (87%-91%). The food supply was reported to be healthier in 2010/2011 compared to 2006/2007. Canteens and/or vending machines offered more often fresh fruits (+8%), sandwiches (+11%), water (+11%) and salad (+7%) and less often sugar sweetened soft drinks (-10%). However, unfavorable changes such as an increase in the supply of pizza slices (+13%) and milk and yoghurt drinks with added sugar (+12%) were also reported. Between 2006/2007 and 2010/2011, the presence of water coolers increased (12% versus 33%) as well as facilities for physical activity (67% versus 77%). However, more schools had vending places of unhealthy foods in the vicinity (73% versus 85%). Compared to 2006/2007, a higher percentage of schools indicated that they have taken actions to stimulate healthy eating behavior (72% versus 80%) or to prevent overweight (34% versus 52%) in 2010/2011. Less schools indicated that they expect to pay more attention to overweight prevention in the near future (56% versus 43%), but none of them expected to pay less attention. CONCLUSIONS: Several aspects of the school environment changed in a positive way. However, schools should be encouraged to contribute to the prevention of overweight, or to continue to do so.

The impact of long-term body mass index patterns on health-related quality of life: the Doetinchem Cohort Study.

Overweight is associated with a reduced health-related quality of life (QOL), but less is known about the impact of long-term body mass index (BMI, calculated as weight (kg)/height (m)(2)) patterns on QOL in adults. In the Dutch Doetinchem Cohort Study (1989-2009) that included 1,677 men and 1,731 women aged 20-66 years, 6 BMI patterns were defined by using 4 measurements over a 15-year period: 1) persistent healthy weight (18.5-24.9, reference pattern); 2) persistent overweight (25.0-29.9); 3) persistent obesity (≥30.0); 4) developing overweight; 5) developing obesity; and 6) switching between BMI categories. For each BMI pattern, adjusted QOL (measured on a 0-100 scale) was estimated at the end of this period. The lowest QOL was observed for persistent obesity of all BMI patterns. It was 5.0 points (P = 0.02) lower for 1 mental dimension in men and 6.2-11.6 points (P < 0.05) lower for 5 (mainly physical) dimensions in women. Developing overweight or obesity scored 1.8-6.3 points (P < 0.05) lower on 2-5 (mainly physical) dimensions. Persistent overweight hardly differed from a persistent healthy weight. In women, switching between BMI categories resulted in a lower QOL on the mental dimensions. Studying long-term BMI patterns over a 15-year period showed that persistent obesity, developing overweight, and developing obesity resulted in a lower QOL-particularly on the physical dimensions-compared with a persistent healthy weight.

Influence of calendar period on the association between BMI and coronary heart disease: a meta-analysis of 31 cohorts.

OBJECTIVE: The association between obesity and coronary heart disease (CHD) may have changed over time, for example due to improved pharmacological treatment of CHD risk factors. This meta-analysis of 31 prospective cohort studies explores the influence of calendar period on CHD risk associated with body mass index (BMI). DESIGN AND METHODS: The relative risks (RRs) of CHD for a five-BMI-unit increment and BMI categories were pooled by means of random effects models. Meta-regression analysis was used to examine the influence of calendar period (>1985 v ≤1985) in univariate and multivariate analyses (including mean population age as a covariate). RESULTS: The age, sex, and smoking adjusted RR (95% confidence intervals) of CHD for a five-BMI-unit increment was 1.28(1.22:1.34). For underweight, overweight and obesity, the RRs (compared to normal weight) were 1.11(0.91:1.36), 1.31(1.22:1.41), and 1.78(1.55:2.04), respectively. The univariate analysis indicated 31% (95%CI: -56:0) lower RR of CHD associated with a five-BMI-unit increment and a 51% (95%CI: -78: -14)) lower RR associated with obesity in studies starting after 1985 (n = 15 and 10, respectively) compared to studies starting in or before 1985 (n = 16 and 10). However, in the multivariate analysis, only mean population age was independently associated with the RRs for a five-BMI-unit increment and obesity (-29(95%CI: -55: -5)) and -31(95%CI: -66:3), respectively) per 10-year increment in mean age). CONCLUSION: This study provides no consistent evidence for a difference in the association between BMI and CHD by calendar period. The mean population age seems to be the most important factor that modifies the association between the risk of CHD and BMI, in which the RR decreases with increasing age.

Associations between changes in anthropometric measures and mortality in old age: a role for mid-upper arm circumference?

OBJECTIVES: In elderly individuals, little is known about changes in different anthropometric measures with respect to mortality. We examined the association between changes in eight anthropometric measures and mortality in an elderly population. DESIGN: Longitudinal study including baseline measurements in 1988-1990 and repeated measures in 1993. SETTING: European towns. PARTICIPANTS: A total of 1061 older adults born in 1913-1918 from the Survey in Europe on Nutrition and the Elderly, A Concerted Action study were included in this study. MEASUREMENTS: Weight, body mass index, waist circumference, waist to hip ratio, waist to height ratio, mid-upper arm circumference (MUAC), triceps skinfold thickness, and corrected arm muscle area were taken during both measurements. RESULTS: A Cox regression model was used to examine the association between anthropometric changes (divided into quintiles, smallest change = reference category) and all-cause and cardiovascular disease mortality over approximately 6 years of follow-up, adjusted for baseline measurement of application, age, sex, smoking, education, physical activity, and major chronic diseases. A decrease in weight (≥3.2 kg), waist circumference (≥3.1 cm), and MUAC (≥1.6 cm and 0.6-1.6 cm) were (near) significantly associated with an all-cause mortality risk of 1.48 (95% CI: 0.99-2.20), 1.52 (95% CI: 1.01-2.31), 1.81 (95% CI: 1.17-2.79), and 1.66 (95% CI: 1.10-2.49), respectively. Also for MUAC, an increase (≥1.3 cm) was significantly associated with an increased all-cause and cardiovascular disease mortality risk [hazard ratio, 1.52 (95% CI: 1.00-2.31) and 1.94 (95% CI: 1.00-3.75), respectively]. CONCLUSION: Associations were observed for decreases in only 3 of 8 anthropometric measures and all-cause mortality. Decreases in MUAC had the strongest association with mortality and was the only measure in which an increase also was associated with mortality. This suggests a role for MUAC in the prediction of mortality in elderly individuals.

The prevalence of physical, sexual and mental abuse among adolescents and the association with BMI status.

BACKGROUND: Studies among adults show an association between abuse and Body Mass Index (BMI) status. When an aberrant BMI status as a consequence of abuse is already prevalent in adolescence, early detection and treatment of abuse might prevent these adolescents from developing serious weight problems and other long-term social, emotional and physical problems in adulthood. Therefore, this study investigated the prevalence of physical, sexual and mental abuse among adolescents and examined the association of these abuse subtypes with BMI status. METHODS: In total, data of 51,856 secondary school students aged 13-16 who had completed a questionnaire on health, well-being and lifestyle were used. BMI was classified into four categories, underweight, normal weight, overweight and obesity. Adolescents reported if they had ever been physically, sexually or mentally abused. Crude and adjusted General Estimation Equation (GEE) analyses were performed to investigate the association between abuse subtypes and BMI status. Analyses were adjusted for ethnicity and parental communication, and stratified for gender and educational level. RESULTS: Eighteen percent of the adolescents reported mental abuse, 7% reported sexual abuse, and 6% reported physical abuse. For underweight, overweight and obese adolescents these percentages were 17%, 25%, and 44%; 7%, 8%, and 16%; and 6%, 8%, 18% respectively. For the entire population, all these subtypes of abuse were associated with being overweight and obese (OR=3.67, 1.79 and 1.50) and all but sexual abuse were associated with underweight (OR=1.21 and 1.12). Stratified analyses showed that physical and sexual abuse were significantly associated with obesity among boys (OR=1.77 and 2.49) and among vocational school students (OR=1.60 and 1.69), and with underweight among girls (OR=1.26 and 0.83). CONCLUSION: Mental abuse was reported by almost half of the obese adolescents and associated with underweight, overweight and obesity. Longitudinal analyses are recommended to explore the causality of and the mechanisms explaining this association between abuse and overweight.

Maintenance of lifestyle changes: 3-year results of the Groningen Overweight and Lifestyle study.

OBJECTIVE: This study aims to evaluate the three-year effect of lifestyle counseling by a nurse practitioner (NP) on physical activity (PA) and dietary intake compared with usual care by a general practitioner (GP). METHODS: At baseline, subjects were randomly allocated to the NP group (n = 225) or to the GP group (n = 232). The NP group received a low-intensive lifestyle intervention for three years by the NP and the GP group received one consultation by the GP and thereafter usual care. PA and dietary intake were assessed with questionnaires at baseline, 1 year follow-up and 3 year follow-up. RESULTS: After three years, leisure-time activity increased and favorable improvements towards a healthy diet were made for both groups. These three-year changes in PA and diet did not differ significantly between groups. Changes in PA and dietary habits after one year were practically maintained after 3 years, because only small relapses were found. CONCLUSION: After three years, subjects were more physically active and had a healthier diet compared to baseline. Lifestyle counseling by NP resulted in similar lifestyle changes compared to GP consultation. PRACTICE IMPLICATIONS: NPs could also advice patients at cardiovascular risk by lifestyle counseling, to possibly reduce GP barriers.

Sitting Behaviors and Mental Health among Workers and Nonworkers: The Role of Weight Status.

Objective. To explore the associations between sitting time in various domains and mental health for workers and nonworkers and the role of weight status. Design. Cross-sectional analyses were performed for 1064 respondents (47% men, mean age 59 years) from the Doetinchem Cohort Study 2008-2009. Sedentary behavior was measured by self-reported time spent sitting during transport, leisure time, and at work. Mental health was assessed by the Mental Health Inventory (MHI-5). BMI was calculated based on measured body height and weight. Results. Neither sitting time during transport nor at work was associated with mental health. In the working population, sitting during leisure time, and particularly TV viewing, was associated with poorer mental health. BMI was an effect modifier in this association with significant positive associations for healthy-weight non-workers and obese workers. Conclusion. Both BMI and working status were effect modifiers in the relation between TV viewing and mental health. More longitudinal research is needed to confirm the results and to gain insight into the causality and the underlying mechanisms for the complex relationships among sedentary behaviors, BMI, working status, and mental health.

Process evaluation of a lifestyle intervention in primary care: implementation issues and the participants' satisfaction of the GOAL study.

The Groningen Overweight and Lifestyle (GOAL) intervention effectively prevents weight gain. The present study describes a process evaluation in which 214 participants in the intervention group received a structured questionnaire within 7 months (a median of 5 months) after the end of the intervention. The authors investigated the content of the intervention (on basis of the participants' recall), the participants' satisfaction of the intervention, the participants' satisfaction with the nurse practitioners (NPs), and the determinants of the participants' satisfaction. In general, the results show that the content corresponded well with the protocol for the intervention, except for the number of telephone calls and the percentage of participants with individualized goals for a healthy lifestyle. The overall satisfaction of the participants was high, and success and perceived success and a low educational level were important determinants for a higher overall satisfaction grade. Furthermore, the NP was considered to be an expert and motivational to learning and keeping up a healthy lifestyle. The authors therefore conclude that the GOAL study is feasible and indicates that the NP is well equipped to treat these patients. However, it is recommended to reinforce the advice given and the lifestyle goals after the first contact sessions.

The prevalence of chronic psychological complaints and emotional exhaustion among overweight and obese workers.

PURPOSE: Literature suggests a relationship between overweight and obesity, and mental health problems, but data regarding prevalence rates are scarce. This study aimed to determine the prevalence of chronic psychological complaints and emotional exhaustion among overweight and obese workers. METHODS: Data were used from the Netherlands Working Conditions Survey (NWCS), which is representative for Dutch employees (n = 43,928). Based on self-reported body mass index (BMI), workers were classified into underweight, healthy weight, overweight, and obesity. Respondents indicated whether they suffered from chronic psychological complaints. Emotional exhaustion was measured by using the UBOS subscale. Logistic regression analyses were used to test differences in prevalence across weight categories, with healthy weight as the reference group. Analyses were stratified for gender, age, education, and occupation. RESULTS: Of the obese workers, 15.7% reported emotional exhaustion and 3.7% reported chronic psychological complaints. These prevalence rates were significantly higher than among healthy weight workers. A significant J shape was found with healthy weight workers reporting the lowest prevalence of both indicators of mental health problems. This J shape was generally also seen among the gender, age, education, and occupation subgroups, though not consistently significant. CONCLUSION: Considering the proportion of obese workers that also suffers from psychological co-morbidities, interventions targeting obesity should take this into account. As weight-related stigma may play a role in the risk for mental health problems among obese workers, future longitudinal research on the mechanisms for the relation between overweight and mental health problems are recommended.

Overweight and school performance among primary school children: the PIAMA birth cohort study.

The aim of this study was to assess the association between overweight and school performance among primary school children prospectively and including a broad range of potential confounding factors. In addition it was investigated what factors mediate this association. For this purpose, data of 2,159 12-year-old children who participated in the Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort study were used. Two indicators of school performance were parental reported when children were 12 years of age and included (i): the score on a standardized achievement test that Dutch children have to complete at the end of their primary education (Cito)-test and (ii): the teacher's advice regarding a child's potential performance level in secondary education. Children's height and weight were measured by a trained research assistant at the age of 8 and by their parents at the age of 12. Overweight was defined using age and gender specific cut-off points. Multivariate regression analyses were performed to assess the association between overweight and school performance. Besides, both confounder and mediation analyses were conducted. Results showed lower Cito-test scores and lower teacher's school-level advice among overweight children. These associations were no longer significant when adjusting for parental educational level, skipping breakfast, and screen time. This study found no independent association between overweight and school performance among primary school children. Results showed strong confounding by parental educational level.

Body mass index and cognitive ability of young children.

OBJECTIVE: This study prospectively assessed the association between body mass index (BMI) and cognitive ability of young children, while accounting for confounding factors. METHODS: The study included 236 children born between 1990 and 1994 participating in a Dutch birth cohort study. Anthropometric data of the children at birth, 4, and 7 years of age were collected from growth records or measured at the Academic Hospital of Maastricht. The Kaufman Assessment Battery for Children (K-ABC) was used to assess cognitive ability at 7 years of age. The association between BMI and cognitive ability was investigated using univariate and multivariate linear regression analyses, including various covariates. RESULTS: Although the results suggest that cognitive ability at 7 years of age decreased with increasing BMI at 4 years and 7 years of age, this association was not significant in any performed analysis. Multivariate analyses showed that maternal intelligence was strongly associated with all scales of the K-ABC as a significant covariate. Adjusting analyses for physical fitness of the child, maternal education, maternal pre-pregnancy BMI, maternal smoking during pregnancy, and birth weight did not change the results. CONCLUSION: This study found no evidence for an association between BMI and cognitive ability of school-aged children.

Preventing weight gain by lifestyle intervention in a general practice setting: three-year results of a randomized controlled trial.

BACKGROUND: Weight regain after initial loss of weight is common, which indicates a need for lifestyle counseling aimed at preventing weight gain instead of weight loss. This study was conducted to determine whether structured lifestyle counseling by nurse practitioners (NPs) group compared with usual care by general practitioners (GP-UC) in overweight and obese patients can prevent (further) weight gain. METHODS: A randomized controlled trial in 11 general practice locations in the Netherlands of 457 patients (body mass index, 25-40 [calculated as weight in kilograms divided by height in meters squared]; mean age, 56 years; 52% female) with either hypertension or dyslipidemia or both. The NP group received lifestyle counseling with guidance of the NP using a standardized software program. The GP-UC group received usual care from their GP. Main outcome measures were changes in body weight, waist circumference, blood pressure, and fasting glucose and blood lipid levels after 3 years. RESULTS: In both groups, approximately 60% of the participants achieved weight maintenance after 3 years. There was no significant difference in mean (SD) weight change and change of waist circumference between the NP and GP-UC groups (weight change: NP group, -1.2% [5.8%], and GP-UC group, -0.6% [5.6%] [P = .37]; and change of waist circumference: NP group, -0.8 [7.1] cm, and GP-UC group, 0.4 [7.2] cm [P = .11]). A significant difference occurred for mean (SD) fasting glucose levels (NP group, -0.02 [0.49] mmol/L, and GP-UC group, 0.10 [0.53] mmol/L [P = .02]) (to convert to milligrams per deciliter, divide by 0.0555) but not for lipid levels and blood pressure. CONCLUSIONS: Lifestyle counseling by NPs did not lead to significantly better prevention of weight gain compared with GPs. In the majority in both groups, lifestyle counseling succeeded in preventing (further) weight gain. TRIAL REGISTRATION: trialregister.nl Identifier: NTR1365.