Majority of Kids Today Will Be Obese Adults
Majority of Kids Today Will Be Obese Adults
Public health implications are dire, expert said
More than half of U.S. children today will be obese as adults, according to a predictive computer model based on current trends.
Given current levels of childhood obesity, 57% of today's children (95% uncertainty interval 55.1%-60%) will be obese by age 35. Roughly half of those will become obese during childhood, said Zachary Ward, a PhD student at the Harvard T.H. Chan School of Public Health in Boston, and colleagues.
The relative risk of adult obesity increased with age and body-mass index (BMI), from 1.17 (95% UI 1.09-1.29) for overweight 2-year-olds to 3.10 (95% UI 2.43-3.65) for 19-year-olds with severe obesity, Ward and colleagues reported in the New England Journal of Medicine.
For children with severe obesity, the chance they would no longer be obese at the age of 35 fell from 21% (95% UI 7.3-47.3) at 2 years of age to 6% (95% UI 2.1-9.9) at the age of 19, the study found.
"Although a broad range of public health and clinical efforts appear to have stabilized early childhood obesity rates ... on the basis of our simulation models, childhood obesity and overweight will continue to be a major health problem in the United States," Ward and colleagues wrote. "Early development of obesity predicted obesity in adulthood, especially for children who were severely obese."
"Given the increased risk of adult obesity, it seems clear that children who are obese are prime candidates for early intervention. Children with severe obesity, a condition that now affects 4.5 million children (6%) in the United States, are at particularly high risk," they said.
The methodology and computer models used in the study were sound and based on some of the most validated data sets in the United States, said Fatima Stanford, MD, a spokesperson for The Obesity Society, in an email to MedPage Today.
"While no one can predict the future, their creation of virtual populations of 1 million children through the age of 19 is likely as close as anyone might get to a prediction of trends of obesity based upon the current trajectory," said Stanford, who specializes in treating obesity at Massachusetts General Hospital in Boston and was not involved in the study.
"The clinical and public health implications of having that many adults with obesity is DIRE," Stanford said. "We must have a wakeup call to ensure that we recognize the current and worsening crisis of obesity not only in the United States but throughout the world."
Too often, instead of treating patients with obesity using multi-disciplinary, multi-sector approaches, clinicians blame the patient and offer limited support, Stanford said.
"We must begin to give obesity the attention that other diseases garner. We go red for HIV/AIDS, we go pink for breast cancer, but what are we doing for obesity?" Stanford said. "We must act, or the projections in the article will become our reality and we will be dealing with the worst public health crisis in modern history -- a trend that is already apparent but ignored more often than not."
Ward and colleagues pooled height and weight data from five nationally representative longitudinal studies that included 41,567 children and adults: the National Longitudinal Survey of Youth, the National Longitudinal Study of Adolescent to Adult Health, the Early Childhood Longitudinal Study–Kindergarten, the Panel Study of Income Dynamics, and the Epidemiologic Follow-up Study of the National Health and Nutrition Examination Survey (NHANES).
Using this data, the study authors created 1,000 virtual populations of 1 million children each. They projected height and weight growth trajectories for these populations up to the age of 35, based on growth curves developed by the CDC. They also adjusted for secular trends in underweight, normal weight, overweight, moderate obesity, and severe obesity which they identified using NHANES data. They defined severe obesity as a BMI of 35 or higher in adults and 120% or more of the 95th percentile in children.
Ward's group noted some limitations to their study, including the assumption that the trends they identified will continue. "However, in our analyses, the age-related trends in relative risk were robust to sensitivity analyses in which no secular trends were applied," they said.
"Our findings highlight the importance of promoting a healthy weight throughout childhood and adulthood. A narrow focus solely on preventing childhood obesity will not avert potential future health damage that may be induced by the ongoing obesity epidemic," they said. "There is evidence that cost-effective approaches with broad population reach could have substantial effects for the present generation of children."