Changes in the effects of living with no siblings or living with grandparents on overweight and obesity in children: Results from a national cohort study in Japan

Abstract

Effects of living without siblings and living with grandparents on overweight and obesity may change with child’s age. We aimed to examine these effects from early childhood to school age at the national level in Japan. Subjects were 43,046 children born in Japan during two weeks in 2001 who were followed annually from 2.5 to 13 years of age in the Longitudinal Survey of Newborns in the 21st Century. We used measured body height and weight reported by participants at each survey and followed the criteria of the International Obesity Task Force to define overweight and obesity. Random-effects logit models by sex, adjusted for time-varying and time-invariant covariates, assessed odds ratios of overweight and obesity for living without siblings and for living with grandparents at each age. The likelihood of overweight and obesity was significantly higher at 8 years and older among children living without siblings, compared with those living with siblings, and odds ratios were highest at 11 years of age in boys (1.87, 95% confidence interval [CI]: 1.49, 2.33) and at 10 and 13 years of age in girls (1.75 [95% CI: 1.36, 2.23] and 1.73 [95% CI: 1.30, 2.31], respectively). It was also significantly higher at 5.5 years and older among children living with grandparents, compared with those living without grandparents, and odds ratios were highest at 10 and 13 years of age in boys (1.53 [95% CI: 1.30, 1.80] and 1.54 [95% CI: 1.27, 1.86], respectively) and at 11 years of age in girls (1.51, 95% CI: 1.24, 1.84). In Japan, living without siblings and living with grandparents may increase the likelihood of overweight and obesity at 8 and 5.5 years and older, respectively. Child’s age should be considered during formulation of strategies for prevention of overweight and obesity in these groups.

Association between grandparent coresidence and weight change among first‐grade Japanese children

“…Previous studies which did not adjust both maternal education and household income 15,[17][18][19] possibly underestimated the primary negative association between grandparent coresidence and weight change in children. A study from Japan that analysed parental report-based weight status among the national cohort found that children living with grandparents are at increased risk of overweight or obesity from preschool to early teens 18 ; however, this study did not examine change in BMI.…”

“…Parents complain about grandparents for promoting snack consumption and being lax about screen time . Grandparent involvement in childcare during infancy is reported to increase the risk of obesity and BMI in preschool children . While several longitudinal studies have been conducted, there is inconsistent evidence for the effect of grandparent coresidence or grandparent involvement in childcare on school‐age children's obesity risk .…”

“…Grandparent involvement in childcare during infancy is reported to increase the risk of obesity and BMI in preschool children . While several longitudinal studies have been conducted, there is inconsistent evidence for the effect of grandparent coresidence or grandparent involvement in childcare on school‐age children's obesity risk . In order to clarify the association, it is necessary to analyse a community representative longitudinal sample of children with objectively measured height and weight and parental socioeconomic and physical information that can be the precursor of the three‐generational household arrangement, and an indicator for biological and genetic disposition …”

“…[15][16][17][18] While several longitudinal studies have been conducted, there is inconsistent evidence for the effect of grandparent coresidence or grandparent involvement in childcare on school-age children's obesity risk. [17][18][19] In order to clarify the association, it is necessary to analyse a community representative longitudinal sample of children with objectively measured height and weight and parental socioeconomic and physical information that can be the precursor of the three-generational household arrangement, [4][5][6] and an indicator for biological and genetic disposition. 20,21 The Adachi Child Health Impact of Living Difficulty (A-CHILD) study was designed to investigate the health and living conditions of children in Adachi City, Tokyo, Japan.…”

Influence of Grandparental Child Care on Childhood Obesity: A Systematic Review and Meta-Analysis

“…The remaining 23 studies that examined the relationship between grandparental child care and children's body weight status were included in the review. 16,17,[19][20][21][22][23][24][25][26][27][28][29][32][33][34][35][36][37][38][39][40][41] Fourteen studies were included in the meta-analyses, as shown in Table 4 (4 studies on BMI z-scores 32,33,37,38 and 10 studies on childhood overweight/obesity risk 19,[22][23][24][25][26]28,[34][35][36] ). Table 2 summarizes the basic characteristics of the 23 included studies.…”