NAFLD Prevalence Rising Among Children but Many Undiagnosed

By Lisa Rapaport

November 20, 2020

(Reuters Health) - The incidence of nonalcoholic fatty liver disease (NAFLD) is rising among children, but not all youth with obesity are getting recommended screening, a study in California suggests.

Researchers examined electronic health record data from Kaiser Permanente Southern California for members aged 5 to 18 years between 2009 and 2018, with records for a total of 7.88 million patient-years. During the study, 54% of children with obesity and 24% of children with overweight got screened for NAFLD.

From 2009 to 2018, the incidence of NAFLD among children in the study increased from 36.0 to 58.2 per 100,000. A total of 3,608 children were diagnosed with NAFLD during the study, according to the report in Pediatrics.

NAFLD diagnoses are becoming more common in part because clinical guidelines from several medical societies including the American Academy of Pediatrics recommend screening children with high BMI, and because a growing number of young people have risk factors for the condition such as obesity, diabetes and high triglycerides, said senior study author Dr. Jeffrey Schwimmer, a professor of pediatrics at the University of California San Diego and director of the Fatty Liver Clinic at Rady Children's Hospital San Diego.

"In our current study we observed that the rate of screening by primary care physicians increased in response to society guidelines," Dr. Schwimmer said by email. "The increase in children being diagnosed with NAFLD is partly because there are greater numbers of children with the problem and partly because there is better detection of the problem."

During the study period, there were a total of 206,117 children with obesity who had well-child visits, and 54% of them got screened for NAFLD.

In addition, there were a total of 212,710 children with overweight who had a well-child visit, and 24% got screened for NAFLD.

Among children with obesity who were screened for NAFLD, the chance of a referral for additional evaluation was more likely from 2012 to 2018 than it was from 2009 to 2011 (odds ratio 1.38).

The chance of a referral for further evaluation also increased when children had higher values for alanine aminotransferase (ALT) and results that were higher than the upper limit of normal (ULN) of 54 U/L for Kaiser Permanente Southern California.

One limitation of the study is that clinicians didn't often use liver histology to diagnose NAFLD, making it possible that some diagnoses were inaccurate, the study team notes. Researchers also lacked data on what proportion of children with NAFLD may have also had fibrosis or NASH.

Another drawback is that blood pressure and elevated insulin levels were not routinely reported for the children in the study, making it difficult to determine how many of them may have had metabolic syndrome, said Dr. Pietro Vajro, a professor of pediatrics at the University of Salerno and director of the pediatrics residency program at the University Hospital of Salerno in Italy.

Even so, the results underscore that more clinicians need to screen for NAFLD and discuss risk factors for the condition with parents of children who have an increased likelihood of developing the condition, Dr. Vajro, who wasn't involved in the study, said by email.

"Previous studies have found that the majority of overweight children seen at general and subspecialty outpatients clinics in the U.S. were not diagnosed and/or did not receive relevant and recommended evaluations and interventions for obesity comorbidities, including NAFLD," Dr. Vajro said.

SOURCE: Pediatrics, online November 19, 2020.