Family structure and childhood obesity: results of the IDEFICS Project.
OBJECTIVE
To analyse the association between family structure and adiposity in children.


METHODS
Cross-sectional and longitudinal analysis of the IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study cohort.


METHODS
Primary schools and kindergartens.


METHODS
Children (n 12 350; aged 7·9 (SD 1·8) years) for the cross-sectional analysis and children (n 5236; at baseline: normal weight, aged 5·9 (SD 1·8) years) for the longitudinal study underwent anthropometry. Family structure was analysed as (i) number and type of cohabiting adults and (ii) number of siblings.


RESULTS
In the cross-sectional analysis, after controlling for covariates, children living with grandparents had significantly higher BMI Z-score than those living with both parents (0·63; 95% CI 0·33, 0·92 v. 0·19; 95% CI 0·17, 0·22; P < 0·01); in addition, the higher the number of siblings, the lower the BMI Z-score (only child = 0·31; 95% CI 0·24, 0·38; 1 sibling = 0·19; 95% CI 0·16, 0·23; 2 siblings = 0·15; 95% CI 0·09, 0·20; >2 siblings = 0·07, 95% CI 0·04, 0·19; P < 0·001). Over the 2-year follow-up, differences in weight gain were observed across family-structure categories. Further, the risk of incidence of overweight/obesity was significantly lower the higher the number of siblings living in the household (v. only child: 1 sibling = 0·74, 95% CI 0·57, 0·96; 2 siblings = 0·63, 95% CI 0·45, 0·88; >2 siblings = 0·40, 95% CI 0·21, 0·77), independently of confounders.


CONCLUSIONS
The study suggests that an independent association between family structure and childhood obesity exists.
1Epidemiology and Population Genetics,Institute of Food Science,National Research Council,Via Roma 64,83100 Avellino,Italy.
Annarita
A
Formisano
2Department of Public Health and Community Medicine,University of Gothenburg,Gothenburg,Sweden.
Monica
M
Hunsberger
3Human Health Sciences,Institute for Public Health Nursing,University of Bremen,Bremen,Germany.
Karin
K
Bammann
5Department of Public Health,Ghent University,Ghent,Belgium.
Barbara
B
Vanaelst
6Department of Pediatrics,University of Pécs Medical School,Pécs,Hungary.
Dénes
D
Molnar
7Growth,Exercise,Nutrition and Development (GENUD) Research Group,University of Zaragoza,Zaragoza,Spain.
Luis A
LA
Moreno
8Research and Education Institute of Child Health,Strovolos,Cyprus.
Michael
M
Tornaritis
9National Institute for Health Development,Tallinn,Estonia.
Toomas
T
Veidebaum
2Department of Public Health and Community Medicine,University of Gothenburg,Gothenburg,Sweden.
Lauren
L
Lissner
1Epidemiology and Population Genetics,Institute of Food Science,National Research Council,Via Roma 64,83100 Avellino,Italy.
Gianvincenzo
G
Barba
1Epidemiology and Population Genetics,Institute of Food Science,National Research Council,Via Roma 64,83100 Avellino,Italy.
Alfonso
A
Siani
D050154:Adiposity / Q000208:ethnology; D015992:Body Mass Index; D002648:Child; D002664:Child Nutritional Physiological Phenomena / Q000208:ethnology; D002675:Child, Preschool; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004032:Diet / Q000009:adverse effects* / Q000208:ethnology; D005060:Europe / Q000453:epidemiology; D005191:Family Characteristics / Q000208:ethnology; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D009749:Nutrition Surveys; D050177:Overweight / Q000453:epidemiology / Q000208:ethnology / Q000209:etiology*; D063766:Pediatric Obesity / Q000453:epidemiology / Q000208:ethnology / Q000209:etiology*; D015995:Prevalence; D012306:Risk; D012574:Schools; D012578:Schools, Nursery