Body Mass Index and Associated Medical Expenditures in the US Among Privately Insured Individuals Aged 2 to 19 Years in 2018

Abstract

ImportanceNearly 40% of US youth aged 2 to 19 years do not have a body mass index (BMI) in the healthy weight category. However, there are no recent estimates for BMI-associated expenditures using clinical or claims data.ObjectiveTo estimate medical expenditures among US youth across all BMI categories along with sex and age groups.Design, Setting, ParticipantsThis cross-sectional study used IQVIA’s ambulatory electronic medical records (AEMR) data set linked with IQVIA’s PharMetrics Plus Claims database from January 2018 through December 2018. Analysis was performed from March 25, 2022, through June 20, 2022. It included a convenience sample of a geographically diverse patient population from AEMR and PharMetrics Plus. The study sample included privately insured individuals with a BMI measurement in 2018 and excluded patients with pregnancy-related visits.ExposureBMI categories.Main Outcomes and MeasuresTotal medical expenditures were estimated using generalized linear model regression with γ distribution and log-link function. For out-of-pocket (OOP) expenditures, a 2-part model was used that included logistic regression to estimate the probability of positive expenditures followed by generalized linear model. Estimates were shown with and without accounting for sex, race and ethnicity, payer type, geographic region, age interacted with sex and BMI categories, and confounding conditions.ResultsThe sample included 205 876 individuals aged 2 to 19 years; 104 066 were male (50.5%) and the median age was 12 years. Compared with those with healthy weight, total and OOP expenditures were higher for all other BMI categories. Differences in total expenditures were highest for those with severe obesity ($909; 95% CI, $600-$1218) followed by underweight ($671; 95% CI, $286-$1055) compared with healthy weight. Differences in OOP expenditures were highest for those with severe obesity ($121; 95% CI, $86-$155) followed by underweight ($117; 95% CI, $78-$157) compared with healthy weight. Having underweight was associated with higher total expenditures at ages 2 to 5 years and 6 to 11 years by $679 (95% CI, $228-$1129) and $1166 (95% CI, $632-$1700), respectively; having severe obesity was associated with higher total expenditures at ages 2 to 5 years, 6 to 11 years, and 12 to 17 years by $1035 (95% CI, $208-$1863), $821 (95% CI, $414-$1227), and $1088 (95% CI, $594-$1582), respectively.Conclusions and RelevanceThe study team found medical expenditures to be higher for all BMI categories when compared with those with healthy weight. These findings may indicate potential economic value of interventions or treatments aimed at reducing BMI-associated health risks.

Current and Future Challenges Regarding Estimating Costs to Determine the Value of Interventions to Manage Unhealthy Weight

“…By definition, confounding variables are not in the causal pathway between BMI and health care expenditures but can still be associated with children’s BMI and increase the health care expenditures of children with these characteristics (Figure). Kumar et al conducted an extensive literature review and used author consensus to identify several characteristics and health conditions that should be included in regression analyses owing to their ability to act as confounders, including race and ethnicity, sex, cancer, congenital malformations, growth hormone deficiency, and eating disorders, among others. Consideration of eating disorders is particularly important because of the high estimated costs ($64.7 billion in 2018 to 2019) …”

“…Even without adjustment for all possible confounders that affect both BMI levels and health care spending (which may be unobservable in the EMR and claims data), the results from the analysis by Kumar et al would still be well suited to predict health care spending based on BMI levels. However, unobserved confounders are more problematic for the causal relationship between BMI levels and health care spending.…”

“…In a world with many competing priorities, stakeholders need to understand the value of investing in childhood obesity policy changes to prioritize funding clinical and policy interventions. The study by Kumar et al in this issue of JAMA Pediatrics aims to estimate the association between children’s body mass index (BMI) class and medical expenditures in the US. Using electronic medical record (EMR) and claims data for privately insured youth, this cross-sectional study found that, relative to healthy weight, having underweight, overweight, and moderate and severe obesity were associated with higher total health care expenditures among those aged 2 to 19 years in 2018.…”

“…The study by Kumar et al contributes to other literature that uses nationally representative data to estimate health care costs attributable to underweight and/or excess weight . One strength of many of these studies is the holistic way in which they focus on both underweight and overweight.…”

“…Based on their findings, Kumar et al suggest that there may be some economic value of interventions or treatments aimed at reducing BMI-associated health risks. Below, we outline 3 themes that should be considered to fully understand the implications of the findings of this and similar studies of BMI class–related expenditures.…”