Pediatric Obesity Research Update | August 2022

Each month, the OMA Pediatric Committee reviews a pediatric-focused obesity research update to help keep you up to date about the latest findings. This month’s update addresses pediatric obesity and anti-obesity medication.

Severe Obesity Associated with Liver Disease Severity in Pediatric Non-alcoholic Fatty Liver Disease

Article Summary

Non-alcoholic fatty liver disease (NAFLD) is a common comorbidity associated with pediatric obesity, affecting one out of every four children with obesity. Additional data is needed to identify high-risk groups in order to determine which children need more intensive interventions. Read the full article.

Article Review

While NAFLD is a common obesity-related comorbidity, not every child with obesity has NAFLD. Studies to identify high-risk patients in order to guide management are key to preventing morbidity (e.g., liver transplant) and mortality. Previous research has examined the association between BMI and liver disease severity in children, finding no association between the two. However, prior studies have had several limitations, including looking at BMI as a continuous variable (as opposed to by BMI category) and possible selection bias, given prior cohorts only included children with severe disease (i.e., biopsy-proven NAFLD and bariatric candidates). As such, the primary objective of this study was to determine whether the severity of pediatric obesity is associated with NAFLD severity.

This was a retrospective cohort study performed at an outpatient steatohepatitis clinic within a large, free-standing, tertiary-care children’s hospital. Patients were classified into weight/BMI categories as follows: overweight (BMI 85^th-95^th), class I obesity (BMI 95^th to

1.19 x 95^th), class II severe obesity (1.2-1.4 x 95^th) and class III severe obesity ( greater than 1.4 x 95^th). Liver disease severity was categorized in three different ways – using biochemical markers, radiographic markers, and histological markers from liver biopsies. These three methodologies reflect the currently utilized clinical modalities for assessing NAFLD.

There were a total of 767 participants in the biochemical cohort. There was a significant linear trend between ALT level and obesity severity. In the radiographic cohort, data from 366 patients were analyzed and showed that liver stiffness and volume increased as obesity severity increased. In the biopsy/histology group, there were 249 participants. The mean NAS (NAFLD Activity Score) did not differ between the groups, but there was a trend toward a significant difference in the proportion of participants with a NAS ≥ 5 (score of ≥ 5 strongly correlated with a diagnosis of “definite NASH”). After controlling for age and metformin use, participants with class II obesity had significantly lower odds of NAS ≥ 5 compared with those with Class III obesity.

In all three cohorts (biochemical, radiographic, histological), there was evidence of more severe liver disease in those with class III obesity. Given that there are currently no available treatment options for pediatric NAFLD aside from weight loss (or weight stabilization in pre-pubertal children), it is imperative to intervene early in the course of obesity and with appropriate intensity. Consider advancing treatment with the use of anti-obesity medications and/or bariatric surgery when criteria are met.

Additional Resources

Find more resources curated by OMA’s Pediatric Committee on our Pediatric Resources page. There you’ll find additional article reviews on various topics related to obesity as well as public resources for clinicians and families.