Is the prevalence of overweight and obesity declining among 4-year-old Swedish children?

Overweight and obesity in a representative sample of schoolchildren - exploring the urban-rural gradient in Sweden

To present the prevalence and urban-rural differences of overweight and obesity in 7-9-year-old Swedish schoolchildren, we used anthropometric data from a nationally representative survey performed in 2008. Trained staff weighed and measured 4538 children in grades 1 and 2 in 94 primary schools. Weight classification was performed using the IOTF reference and school areas were classified based on level of urbanization and area-level education. Overweight was found in 17% of the children including 3% obese. For overweight, odds-ratios were 1.33 and 1.61 (significant) in semi-urban and rural areas, relative to urban areas. After adjusting for area-level education, differences by degree of urbanisation were greatly attenuated and non-significant. For obesity urban-rural differences were observed in boys only and remained after adjustment for area-level education. For area-level education, risk estimates were significantly elevated and unaffected by urbanization and gender, odds-ratios 1.75 and 2.21 for overweight and 2.62 and 3.69 for obesity, in medium- and low-education areas compared to high-education areas. This supports earlier reports identifying areas with low socioeconomic status as high-risk areas for overweight and obesity. However, this study also suggests that gender should be considered when targeting children in urban as well as rural communities for health promoting interventions.

Toddlers get slimmer while adolescents get fatter--BMI distribution in five birth cohorts from four decades in Finland

AIM

To investigate the trends in the size of Finnish children in five birth cohorts from four decades.

METHODS

This is a retrospective longitudinal growth pattern study on children representing five birth cohorts: 1974, 1981, 1991, 1995 and 2001 from the city of Tampere and three rural municipalities. Growth data were collected from birth to 15 years of age, except in birth cohorts 1995 and 2001 until 12 and 5 years. Body mass index (BMI, kg/m²) was calculated. Pearson's chi-square test was used in analysis.

RESULTS

The 50th percentile of BMI at birth varied between the 1970's and 2000's (boys: p<0.001, girls: p=0.02), with increase seen in girls. The 50th BMI percentile remained unchanged in 6-month-aged boys, whereas in girls, it varied inconsistent (p=0.04). At 1 and 2 years of age, the 15th, 50th, 85th and 95th BMI percentiles decreased (p=0.26 to <0.001). The 50th BMI percentile remained fairly constant at 5 and 7 years of age. In 12- and 15-year-old boys, the 50th, 85th and 95th percentiles of BMI showed a marked increase (p=0.01 to <0.001). In 12-year-old girls, only the 85th BMI percentile increased (p=0.03).

CONCLUSIONS

During the last three decades, Finnish toddlers have become markedly slimmer. Concurrently, an opposite change has taken place in adolescent boys.

Thirty years of prospective nationwide incidence of childhood type 1 diabetes: the accelerating increase by time tends to level off in Sweden

OBJECTIVE

During the past few decades, a rapidly increasing incidence of childhood type 1 diabetes (T1D) has been reported from many parts of the world. The change over time has been partly explained by changes in lifestyle causing rapid early growth and weight development. The current study models and analyzes the time trend by age, sex, and birth cohort in an exceptionally large study group.

RESEARCH DESIGN AND METHODS

The present analysis involved 14,721 incident cases of T1D with an onset of 0-14.9 years that were recorded in the nationwide Swedish Childhood Diabetes Registry from 1978 to 2007. Data were analyzed using generalized additive models.

RESULTS

Age- and sex-specific incidence rates varied from 21.6 (95% CI 19.4-23.9) during 1978-1980 to 43.9 (95% CI 40.7-47.3) during 2005-2007. Cumulative incidence by birth cohort shifted to a younger age at onset during the first 22 years, but from the birth year 2000 a statistically significant reversed trend (P < 0.01) was seen.

CONCLUSIONS

Childhood T1D increased dramatically and shifted to a younger age at onset the first 22 years of the study period. We report a reversed trend, starting in 2000, indicating a change in nongenetic risk factors affecting specifically young children.

Change in prevalence of overweight and obesity in Finnish children - comparison between 1974 and 2001

OBJECTIVE

To analyse the possible changes in the prevalence of overweight and obesity comparing birth cohorts from four different decades in Finland.

DESIGN

A retrospective longitudinal growth study.

METHODS

The subjects representing five birth cohorts: 1974 (n = 1109), 1981 (n = 987), 1991 (n = 586), 1995 (n = 856) and 2001 (n = 766) in the city of Tampere and three rural municipalities in Finland. Data included five consecutive height and weight measurements from 2 to 15 years of age. Normal weight, overweight and obesity at the time points were classified by body mass index (BMI, kg/m(2) ) according to international age- and gender-specific BMI cut-off points. The chi-square test was used to analyse the differences in the between birth cohorts.

RESULTS

The combined prevalence of overweight and obesity decreased significantly in 2-year-old boys (p = 0.009) and girls (p = 0.002) from 1974 to 2001. Insignificant fluctuation was seen in 5- and 7-year-old children. Both the prevalence of obesity and the combined prevalence of overweight and obesity showed a significant increase in 12- (p = 0.031 and p < 0.001) and 15-year-old boys (p < 0.001 in both) from the 1970s to 2000s. In girls, the prevalence of obesity as well as the combined prevalence of overweight and obesity increased significantly in the age group of 12 years (p = 0.023), but not in that of 15 years.

CONCLUSIONS

During the last three decades, overweight and obesity have become clearly more prevalent in Finnish young adolescents. This trend has been more obvious in boys than in girls. At the same time, 2-year-old children have shown an opposite trend.

Family stress and BMI in young children

AIM

The aim of this study was to investigate if family stress and parental attachment style are associated with body mass index (BMI) in young children, and identify possible explanations.

METHODS

A cross-sectional survey with a two-stage design was used. Parents of 873 children participated. They completed a demographic questionnaire, the Swedish Parenthood Stress Questionnaire (SPSQ), the Relationship Questionnaire (RQ) and reported their children's television-viewing habits (as a marker of physical activity). Children's height, weight and BMI were obtained from a general population-based register, BASTA. Associations with over- and underweight in children were assessed using multiple logistic regression analysis.

RESULTS

Family stress indicated by SPSQ-score was associated with suboptimal BMI. Maternal, but not paternal, SPSQ-stress score was statistically significantly associated with overweight and underweight, with adjusted odds ratios (and 95% confidence interval) of 4.61 (3.11-6.84; p < 0.001) and 3.08 (1.64-5.81; p < 0.001) respectively. Associations between childhood BMI and parental attachment style were identified, but were not independent of maternal SPSQ-score.

CONCLUSION

Our findings support a role for family stress in development of both overweight and underweight among young children. This is likely to be attributed to behavioural mechanisms but a more direct metabolic influence of stress could also be involved.

Overweight and obesity in Norwegian children: prevalence and socio-demographic risk factors

AIM

The aim of this study was to estimate the prevalence of childhood overweight and obesity and to identify socio-demographic risk factors in Norwegian children.

METHODS

The body mass index of 6386 children aged 2-19 years was compared with the International Obesity Task Force (IOTF) cut-off values to estimate the prevalence of overweight including obesity (OWOB) and obesity (OB). The effect of socio-demographic factors on this prevalence was analysed using multiple ordinal logistic regression analysis in a subsample of 3793 children.

RESULTS

The overall prevalence of OWOB was 13.8% (13.2% in boys and 14.5% in girls, p = 0.146), but the prevalence was higher in primary school children aged 6-11 years (17%, p < 0.001). The risk of being OWOB or OB increased in children with fever siblings (p = 0.003) and with lower parental educational level (p = 0.001). There was no association with parental employment status, single-parent families or origin.

CONCLUSION

The prevalence of OWOB and OB in Norwegian primary school children is of concern. Socio-demographic factors have pronounced effects on the current prevalence of overweight and obesity in a cohort of Norwegian children. This knowledge could help to work out strategies to reduce the burden of overweight and obesity in children.