Abstract and Introduction
Abstract
We investigated the influence of parents' weight status on their children's growth trajectories and its association with age at onset of overweight and obesity. We used 16,396 height and weight records from 3,284 youths from the Panel Study of Income Dynamics, followed across childhood into adulthood (United States, 1997–2017). Across age groups, we modeled body mass index trajectories (ages 5–32 years) according to parents' weight status, using mixed-effect models to estimate age at onset of overweight and obesity and proportion with obesity from childhood to adulthood. There were large differences in growth patterns according to parents' weight status: Children of parents with obesity had, on average, overweight at age 6 (95% confidence interval (CI): 5, 7) and steep growth trajectories until age 12; children of normal-weight parents had slower increases in body mass index, reaching overweight on average at age 25 (95% CI: 24, 27). By age 30, 30% (95% CI: 28, 31) of youths had obesity. Differences in early-life growth persisted into adulthood: 48% (95% CI: 45, 52) of adult children of parents with obesity had obesity versus 16% (95% CI: 14, 19) of those of normal-weight parents. Trajectories to unhealthy weight were heavily influenced by parents' weight status, especially before age 12, children of parents with obesity having overweight 19 earlier in life than children of normal-weight parents.
Introduction
Obesity is a major health problem in the United States, with >40% of the adult population having a body mass index (BMI) equivalent to obesity.[1–3] Risks of obesity can become established in childhood,[4–9] and once a youth begins to accumulate unhealthy weight, reversing to normal weight rarely occurs.[10–12] These patterns are especially concerning because the age when obesity is first observed and the duration of overweight and obesity during childhood and adolescence are associated with the development of cardiometabolic conditions in adulthood.[6,8,9,13,14] This evidence highlights that knowledge is needed about how to identify the children who are likely to progress to obesity in adulthood and whether there is a specific (age) window of opportunity.
Parents and children share many health characteristics, and weight status is among these.[6,15–23] Parent-child similarities in body weight may originate from genetic predispositions,[24,25] intrauterine exposure,[26] shared life conditions, shared environments, and habits and preferences formed during childhood.[16,25,27] Even among children with normal weight up to age 17 years, those whose parents have obesity have a higher risk of developing obesity in adulthood.[6]
The premise of this study is that parents' weight status is a determinant for their children's growth trajectories and that children whose parents have obesity may follow different age-specific growth patterns, including likelihood and timing of overweight and obesity, compared with those of parents without obesity. We used data from the Panel Study of Income Dynamics (PSID),[28] a national, longitudinal study with 20 years of data on height and weight in children and their parents. These data provide an unique opportunity to quantify links between parents' weight status and children's growth trajectories.
We examined differences between the growth patterns of children of parents with obesity and those whose parents did not have obesity. We modeled growth trajectories from ages 5 to 32 years to assess the relationship of parents' weight status and the age at onset of overweight and obesity in their children.
Am J Epidemiol. 2022;191(11):1877-1885. © 2022 Oxford University Press