Socioeconomic inequality in overweight/obesity among US children: NHANES 2001 to 2018

Abstract

BackgroundPrevious research has found that the prevalence of childhood overweight/obesity varies depending on household income, ethnicity, and sex. The goal of our research is to examine changes over time in socioeconomic inequality and the prevalence of overweight/obesity among American children under five by sex and ethnicity.MethodsThis cross-sectional analysis used data from the National Health and Nutrition Examination Surveys (NHANES) collected from 2001–02 to 2017–18. Overweight/obesity in children under five [Body Mass Index (BMI)-for-age z-score >2 standard deviations] was defined according to the World Health Organization (WHO) growth reference standard. The slope inequality index (SII) and the concentration index (CIX) were used to measure the socioeconomic inequality in overweight/obesity.ResultsBetween 2001–02 and 2011–12, childhood overweight/obesity in the United States decreased from 7.3% to 6.3%, and had increased to 8.1% by 2017–18. However, this pattern varied widely by ethnicity and sex. For both the 2015–16 and 2017–18 surveys, overweight/obesity was more concentrated in the poorest household quintile for overall Caucasian children ((SII = −11.83, IC 95% = −23.17, −0.49 and CIX = −7.368, IC 95% = −13.92, −0.82) and (SII = −11.52, IC 95% = −22.13, −0.91 and CIX = −7.24, IC 95% = −13.27, −1.21), respectively) and for males of other ethnicities [(SII = −13.93, IC 95% = −26.95, −0.92) and CIX = −8.55, IC 95% = −0.86, −16.25] and (SII = −21.19, IC 95% = −40.65, −1.74) and CIX = −13.11, IC 95% = −1.42, −24.80), respectively). In the last three surveys, overweight/obesity was also more concentrated in the poorest household quintile for the overall children of other ethnicities. With the exception of African American females in the 2013–14 survey, for whom overweight/obesity was significantly concentrated in a quintile of the richest households (SII = 12.60, 95% CI = 0.24, 24.97 and CIX = 7.86, 95% CI = 15.59, 0.12); overweight/obesity was found to be concentrated in the richest household quintile for overall African American children, but not significantly so.ConclusionsOur findings give an update and reinforce the notion that overweight/obesity in children under the age of five has increased and that related wealth inequalities are a public health problem in the United States.

The Contribution of the Underlying Factors to Socioeconomic Inequalities in Obesity: A Life Course Perspective

“…In mid-low income countries like Iran, it was reported that CIs of obesity in childhood were between 0.03 and 0.10 [ 30 , 31 ]. In the Europe and US, however, the socioeconomic status was often found to be inversely associated with child and adolescent obesity [ 32 – 34 ], and the similar relationship was observed among adult women, except for adult men [ 35 , 36 ]. Raftopoulou and Trasfi combined CI and Foster-Greer-Thorbecke index to estimate the inequality in obesity beyond the obesity threshold and found that inequalities in depth and severity of obesity were much greater for the poor compared to the rich in Spain [ 37 ].…”

Pharmacological interventions for the management of children and adolescents living with obesity—An update of a Cochrane systematic review with meta‐analyses

“…It is well known that the incidence and prevalence of obesity in childhood and adolescence is unequal, represented by a higher risk for obesity in socioeconomically disadvantaged children and adolescents. [99][100][101] Furthermore, there are social disparities in obesity management even though the evidence base is weak. 102 It is therefore imperative that drug intervention is only considered as part of a suite of options addressing obesity as a complex and chronic disease with effective comorbidity management and careful adverse event monitoring that is underpinned by a person-centred care approach, delivering healthcare with dignity and respect.…”

“…It is well known that the incidence and prevalence of obesity in childhood and adolescence is unequal, represented by a higher risk for obesity in socioeconomically disadvantaged children and adolescents 99–101 . Furthermore, there are social disparities in obesity management even though the evidence base is weak 102 .…”

Trends in childhood body mass index between 1936 and 2011 showed that underweight remained more common than obesity among 398 970 Danish school children

“…6 However, these tendencies should be interpreted cautiously as the overall trends may mask important differences by socioeconomic status and ethnicity as seen in Denmark and elsewhere. [26][27][28] Across the study period, the shape of the BMI distribution changed and became more right-skewed, whereas the median and the lower parts of the BMI distribution remained relatively constant.…”

“…A recent meta‐analysis of European children aged 2–13 years found that in most European countries, the prevalence of overweight and obesity has stabilised from 1999 to 2016 6 . However, these tendencies should be interpreted cautiously as the overall trends may mask important differences by socioeconomic status and ethnicity as seen in Denmark and elsewhere 26–28 …”