Factors Associated With Changes in Weight-status in Danish School Children With Obesity
Study Details
Study Description
Brief Summary
Childhood obesity is increasing worldwide and causes a major health concern. Only limited insight exists into the natural history of childhood obesity at children already classified as obese. It is necessary to identify possible windows of opportunities to initiate treatment and to prevent further weight gain later in life.
This observational study follows the natural weight change in younger children with obesity without known intervention. The objective is to identify factors associated with achieving normal weight, having persistent obesity, or reaching higher levels of obesity, when following children age 5-10 years with obesity through childhood and puberty.
Data from health check-ups at school and Danish registries will be used to answer the research question.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
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Detailed Description
Only limited insight exists into the natural history of childhood obesity at children already classified as obese. It is necessary to identify possible windows of opportunities to initiate treatment and to prevent further weight gain later in life.
High Body Mass Index (BMI) or weight status early in life seems to predict the risk of persisting obesity and indicating BMI as an important predictor for the chance of remission. High birthweight has also been associated with poor chance of normalizing weight, when following children with obesity from kindergarten to the 8th grade, indicating that severe obesity can be detectable from early childhood.
Children with severe obesity (iso-BMI ≥ 35) have been observed to gain weight with a faster rate and with a critical period between 12 to 14 years of age, compared to children with less-severe obesity (iso-BMI < 35). Another report observes, that having obesity at the age of six was associated with obesity after puberty, while no such association was observed for younger children (six years). Hereby suggesting that children at a younger age have chance of achieving remission of obesity, than children classified as having obesity later in life.
Other factors such as sex, ethnicity and interpersonal skills have also been observed to influence the chance of normalizing weight, when following children with obesity from 5th to 8th grade.
This study aims to identify factors associated with achieving normal weight (iso-BMI 18.5-25 kg/m2), when following children (age 5-10 yrs.) with obesity through childhood and puberty.
In addition, to identify factors associated with having persisting obesity (iso-BMI ≥ 30 kg/m2), or reaching a higher level of obesity (highest 20% increase in BMI z-score from baseline)
The participants:
This study includes children 5 to 10 years of age living with obesity from the city of Aarhus, Denmark.
The inclusion criteria:
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Baseline visit between January 1st. 2010 and March 17th. 2018.
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Obesity, defined by the International Obesity Task Force (IOTF) cutoff for obesity
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Minimum three years of follow-up
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Five to ten years of age
The exclusion criteria:
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Children treated in a community-based lifestyle intervention.
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Children registered as having declined participation in a community-based lifestyle intervention.
Data sources:
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Observations containing anthropometrics have been extracted from TM-Sund for each child. TM-Sund is a database used in Aarhus municipality to store data on anthropomet-rics obtained at health checks at the school (read more on https://www.solteq.com/da).
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Data on family structure, socioeconomic status (SES), immigration status and psychiatric diagnoses (child and parents) will be obtained from Danish registries at Statistics Den-mark.
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The local registry at Aarhus Municipality will be used to identify and exclude children
- treated in or 2) declined participation in a lifestyle intervention.
Statistics:
The IOTF cut-offs for weight status at the last obtained observation will be used to define the groups (normal weight iso-BMI < 25 kg/m2, overweight iso-BMI 25-30 kg/m2, and obesity iso-BMI ≥ 30 kg/m2)
Groups:
The IOTF cut-offs for weight status at the last obtained observation will be used to define the groups.
Primary outcome, normalizing weight status:
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Normal weight, (iso-BMI < 25 kg/m2)
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Overweight and obesity (iso-BMI ≥ 25 kg/m2)
Secondary outcome
- persistent obesity at last observation:
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Persistent obesity (iso-BMI ≥ 30 kg/m2)
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Remission, normal weight and overweight (iso-BMI 30 ≤)
- highest increase in BMI z-score at last observation from baseline: Lowest increase BMI z-score from baseline (below the 20th percentile) Highest increase BMI z-score from baseline (above the 20th percentile)
A logistic regression analysis will be used to identify baseline factors associated with the group of children normalizing weight, persistent obesity and highest increase of BMI z-score (above the 20th centile) at the last observation, respectively. The models will be adjusted for no more than 1 co-variable per 10 observations.
Observations for each child will be weighted by the fraction of the maximum possible follow-up relative to the maximum follow-up observed in the cohort, to take into account the differences in length of follow-up.
Ethics & permissions:
The local committee on health ethics have approved the overall project and data transfer (rec.no 1-45-70-27-2).
The project has achieved approval from The Danish Data Protection Agency and the Principal Investigator has been granted access to data from registers from Denmark Statistics.
The researchers have no conflict of interest to declare.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Normalizing weight Children classified as having normalized weight (iso-BMI 18.5-25 for age and sex) at the last observation defined by IOTF. |
Other: Change of weight class to normal weight
The exposure is the change of weight class from obesity to normal weight during a follow-up period without known intervention.
|
| Overweight or obesity Children classified as having overweight or obesity (iso-BMI 25 ≤ for age and sex) at the last observation defined by IOTF. |
Outcome Measures
Primary Outcome Measures
- Factors associated with changes in weight-status in Danish school children: from obesity to normal weight. [Children with a baseline visit between January the 1st 2010 and March the 18nd 2018 will be included. The children will be followed until March the 18nd 2021.]
Factors associated with changes in weight-status in Danish school children (age 5-10 years) from obesity or normal weight. Only children with minimum 3 years of follow-up will be included. Children treated in or declining treatment in a lifestyle intervention for obesity will be excluded.
Secondary Outcome Measures
- Factors associated with persisting obesity in Danish school children with obese. [Children with a baseline visit between January the 1st 2010 and March the 18nd 2018 will be included. The children will be followed until March the 18nd 2021.]
Factors associated persisting obesity in Danish school children (age 5-10 years) compared to children obtaining remission of obesity. Only children with obesity at baseline and minimum 3 years of follow-up will be included. Children treated in or declining treatment in a lifestyle intervention for obesity will be excluded.
- Factors associated with the highest increase in BMI z-score (above the 20th percentile) in Danish school children with obese. [Children with a baseline visit between January the 1st 2010 and March the 18nd 2018 will be included. The children will be followed until March the 18nd 2021.]
Factors associated the highest increase in BMI z-score (above the 20th percentile in changes from baseline) in Danish school children (age 5-10 years) compared to children with lower increase or decrease in BMI z-score (below the 20th percentile within the cohort). Only children with minimum 3 years of follow-up will be included. Children treated in or declining treatment in a lifestyle intervention for obesity will be excluded.
Eligibility Criteria
Criteria
Inclusion Criteria:
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Baseline visit between January 1st. 2010 and March 17th 2018.
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Minimum one observation with obesity
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Minimum three years of follow-up from baseline
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Children age 5-10 years
Exclusion Criteria:
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Children registered in a community-based lifestyle intervention.
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Children registered as having declined participation in a community-based lifestyle intervention.
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Steno Diabetes Center Aarhus | Aarhus N | Denmark | 8200 |
Sponsors and Collaborators
- University of Aarhus
- Child and Youth, Aarhus Municipality
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- Journal no.: 2022-0367531