A within-sibling pair analysis of lifestyle behaviours and BMI z-score in the multi-centre I.Family study

• Published in: Nutrition, metabolism, and cardiovascular diseases Vol. 29; no. 6; pp. 580 - 589
• Main Authors: Bogl, L.H., Mehlig, K., Intemann, T., Masip, G., Keski-Rahkonen, A., Russo, P., Michels, N., Reisch, L., Pala, V., Johnson, L., Molnár, D., Tornaritis, M., Veidebaum, T., Moreno, L., Ahrens, W., Lissner, L., Kaprio, J., Hebestreit, A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2019
• Subjects: Adolescent; Adolescent Behavior; Age Factors; association; Body Mass Index; Cardiac and Cardiovascular Systems; Cardiovascular System & Cardiology; Child; Child Behavior; Cross-Sectional Studies; Diet; dietary-intake; Endocrinology & Metabolism; Energy Intake; Europe - epidemiology; european children; Exercise; Feeding Behavior; Female; Humans; Kardiologi; Life Style; Male; MVPA; Nutrition & Dietetics; Nutrition and Dietetics; Näringslära; obesity; overweight; Overweight-discordant; Pediatric Obesity - epidemiology; Pediatric Obesity - physiopathology; Pediatric Obesity - prevention & control; Pediatric Obesity - psychology; physical-activity; risk; Risk Assessment; Risk Factors; Risk Reduction Behavior; Screen Time; Sex Factors; Sibling pairs; Siblings - psychology; Sleep; Twin pairs; Twins - psychology; weight; Europe; Energy intake; Adolescents and Adult Nutrition Assessment; Body mass index; Lifestyle and the Environment; Twin pairs; PA Physical activity; 24HDR 24-hour dietary recall; TV Television; IOTF International Obesity Task Force; Overweight-discordant; Sibling pairs; MVPA
• ISSN: 0939-4753; 1590-3729
• DOI: 10.1016/j.numecd.2019.01.017

By investigating differences in lifestyle behaviours and BMI in sibling pairs, family-level confounding is minimized and causal inference is improved, compared to cross-sectional studies of unrelated children. Thus, we aimed to investigate within-sibling pair differences in different lifestyle behaviours and differences in BMI z-scores in children and adolescents. We examined three groups of sibling pairs 1) all same-sex sibling pairs with maximum 4 years age difference (n = 1209 pairs from 1072 families in 8 countries, mean age 10.7 years, standard deviation 2.4 years), 2) sibling pairs discordant for overweight (n = 262) and 3) twin pairs (n = 85). Usual dietary intake was estimated by 24-h recalls and time spent in light (LPA) and moderate-to-vigorous physical activity (MVPA) was measured by accelerometers. Screen time, sleep and dieting for weight loss were assessed by questionnaires. Within all 3 groups of sibling pairs, more time in MVPA was associated with lower BMI z-score. Higher energy intake was associated with higher BMI z-score within twin pairs and within all sibling pairs who were not currently dieting for weight loss. Regarding LPA, screen time or sleep duration, no or inconsistent associations were observed for the three groups of sibling pairs. MVPA and energy intake were associated with BMI differences within sibling and twin pairs growing up in the same home, thus independent of family-level confounding factors. Future studies should explore whether genetic variants regulating appetite or energy expenditure behaviours account for weight differences in sibling pairs. •Some lifestyle behaviours are associated with BMI differences within sibling pairs.•More time in MVPA was associated with lower BMI z-score within sibling pairs.•Higher energy intake was associated with higher BMI z-score within twin pairs.•Sibling pairs discordant for overweight during childhood differ in MVPA.•Weight loss attempts are more common among siblings with overweight.