Despite the decline in the pediatric population, the number of "pediatric chronic multiple diseases" and the cost of treatment has increased, providing another reason for maintaining the pediatric specialty care system, a report said.

The Health Insurance Review and Assessment Service (HIRA) said so in a study, "Analysis of Changes in the Number of Pediatric Complex Chronic Disease Patients and Medical Expenses through Analysis of Health Insurance Claims Data," recently published in HIRA Research, the agency’s official journal.

The research team analyzed health insurance claims data of pediatric patients under 20 hospitalized or visited outpatient clinics for pediatric complex chronic diseases from 2011 to 2021.

The number of pediatric MCDs increased by more than 100,000 in past decade

The analysis found that pediatric patients under 20 with multiple chronic diseases (MCD) increased by 106,000, from 345,000 in 2011 to 451,000 in 2021. The number of people under 20 decreased at an annual average rate of 2.89 percent during the same period, while the number of those with MCDs increased by 2.71 percent.

As a result, the proportion of people with CMDs in the pediatric population increased from 3.04 percent in 2011 to 5.33 percent in 2021.

The number of children and adolescents with multiple chronic conditions who used healthcare services repeatedly also continued to grow, increasing by 72,000 from 157,000 in 2011 to 229,000 in 2021, marking an annual growth rate of 3.83 percent. Their share of the pediatric population increased from 1.39 percent to 2.71 percent over the same period.

By age, pediatric MCD patients with repeat visits, the proportion of patients under one year of age remained constant between 3.67 percent and 3.90 percent, while the share of adolescents aged 13-19 years decreased from 45.15 percent in 2011 to 38.51 percent in 2021.

The proportion of patients with two or more MCD diagnosis groups increased from 35.8 percent to 43.7 percent.

The share of patients by diagnosis group in the MCD patients also changed over the decade. In 2011, the neurological and neuromuscular disease group" had the highest percentage of patients. In 2021, however, "other congenital or genetic disease group" showed the highest percentage of patients.

The largest change was in the "metabolic disease group," recording 16.90 percent of patients in 2011 and 29.14 percent in 2021.

In terms of multimorbidity diagnoses by age, children under the age of one showed the highest share of patients in the cardiovascular group from 2011 to 2021, and children ages 1-6 also recorded the highest share of patients in the cardiovascular group, as did children under the age of one.

Those aged 7-12 marked the highest number of patients with neurological and neuromuscular diseases in 2011. However, the number of patients with other congenital and genetic diseases gradually increased to take the top spot in 2021. Those aged 13 and older showed a decreasing trend in neurological and neuromuscular diseases and an upturn in metabolic diseases.

Medical expenses for pediatric MCD patients rose by 4.91% a year on average

The medical expenses for pediatric MCD patients increased from 475.7 billion won ($365.6 million) in 2011 to 768.5 billion won in 2021 after adjusting for the increased reimbursement rate. In particular, the overall medical expenses for pediatric and adolescent patients increased at an average annual rate of 0.43 percent. Still, the medical expenses for MCDs rose at a much higher rate of 4.91 percent.

Accordingly, the share of medical expenses for patients with MCDs increased from 12.34 percent in 2011 to 19.11 percent in 2021, and the share of medical expenses for patients with multiple chronic diseases reached 20.71 percent in 2020 when the total number of patients decreased.

The share of hospitalization expenditures for MCD patients grew from 22.70 percent in 2011 to 30.59 percent of total hospitalization expenses in 2021, and inpatient expenditures were 1.93 times higher than outpatient costs in 2021.

“The number of children and adolescents with MCDs is increasing, and the severity is becoming more complex," the research team said. "These results show that the decline of the pediatric population should not weaken the pediatric care system but should be strengthened while maintaining a specialized care system."