The rapid decline in deaths comes as 30 years of global data reveal that progress has been uneven and there is a growing need for equitable pediatric IBD care.
Study: Changing burden of early-onset inflammatory bowel disease: A global analysis. Image credit: Marko Aliaksandr / Shutterstock
In a recent study published in the journal pediatric researchA group of researchers used Global Burden of Disease (GBD) 2021 data to assess the global burden, time trends, and socio-economic disparities of early-onset inflammatory bowel disease (EO-IBD) in children under 10 years of age.
background
It is estimated that in 2021, more than 1,000 children worldwide will develop EO-IBD. EO-IBD is a lifelong condition that can interfere with growth, education, and mental health.
Although significant advances have been made in the treatment of this disease, its reported burden varies widely between countries and may reflect differences in healthcare access, diagnostic capacity, reporting practices, and socio-economic development. EO-IBD affects children under 10 years of age and poses unique clinical and public health problems that go beyond medicine.
Understanding how the burden varies by region and population is essential to improving pediatric health services and reducing inequalities.
About research
Researchers analyzed modeled estimates from the GBD 2021 database, which provides standardized health estimates for 204 countries and territories from 1990 to 2021.
This study focused on GBD estimates of inflammatory bowel disease (IBD) in children younger than 10 years, rather than individual records specifying age at diagnosis, and investigated incidence, prevalence, mortality, and disability-adjusted life years in this age group.
Results included age-standardized morbidity and mortality rates (ASIR and ASDR), as well as separate comparisons by geographic region, country, and broad age groups of 0-4 and 5-9 years.
Statistical analyzes were performed using R software version 4.4.1 and included geospatial mapping and regression analysis of disease burden. Temporal trends were assessed using estimated annual changes over the entire study period and segmented annual changes over specific time periods with corresponding 95% confidence intervals.
Disease rates were compared across socio-demographic index (SDI) categories based on age, sex, per capita income of persons under 25 years of age, educational attainment, and fertility.
Rather than directly measuring quality of care, the frontier analysis compared the observed age-standardized rates to the modeled minimum values for each SDI level. Health inequalities were assessed using the Slope Inequality Index and the Concentration Inequality Index.
Moreover, decomposition analysis showed that population growth, changes in age structure, and changes in epidemiological incidence contributed to changes in disease burden. GBD estimates are reported with 95% uncertainty intervals, 95% confidence intervals were used in regression-based analyses, and statistical significance was defined at α = 0.05.
Research results
From 1990 to 2021, the global burden of EO-IBD showed contrasting trends. The estimated number of deaths decreased from 1,008.54 to 293.14, a decrease of about 71%. At the same time, the estimated number of new infections increased slightly from 1,172.63 to 1,322.58. While the ASDR decreased significantly from 0.083 to 0.022 per 100,000 children, the ASIR was approximately 0.10 per 100,000 in both 1990 and 2021, indicating little net change over the entire period.
The estimated annual rate of change was -4.15% for ASDR, with a 95% confidence interval of -4.29% to -4.00%, and -0.11% for ASIR, with a 95% confidence interval of -0.29% to 0.07%, indicating a marked decline in mortality but relatively stable incidence. The ASIR trend was not statistically significant as the confidence interval included zero.
The estimated number of prevalent cases increased from 2,659.1 to 3,037.9, but disability-adjusted life years decreased by approximately 70%. This is consistent with a reduction in premature deaths and potentially improved disease management, despite an increase in the number of children living with the disease.
Significant variation was observed between SDI categories. In 2021, medium-SDI regions had the highest estimated number of deaths, while high-SDI regions had the lowest number of deaths despite having the highest number of new infections.
The highest ASIR occurred in the high SDI region, and the lowest ASIR occurred in the medium SDI region. Although the estimated decline in mortality was largest in high- and medium-SDI regions and smallest in low-SDI regions, estimates for low-SDI were highly uncertain, highlighting uneven progress in reducing disease burden across different levels of development.
Regional analysis demonstrated high geographic variation. Global mortality rates have declined in many regions around the world, particularly in East Asia, high-income regions of Asia-Pacific, and high-medium SDI regions. In contrast, eastern, southern, and western sub-Saharan Africa experienced slower declines.
Incidence increased most markedly in East Asia, middle-SDI regions, North Africa and the Middle East, while high-income North America, Western Europe, and high-SDI regions recorded declines in incidence.
In most regions, the incidence was higher in children aged 5 to 9 years than in children aged 0 to 4 years. Globally, the age distribution of deaths varied geographically, but mortality rates were lower among older age groups. However, because we only used two broad age groups, we were unable to establish definitive age-related trends.
Sex-specific analyzes also revealed regional differences, with some regions having higher mortality and incidence rates in men, whereas some resource-limited settings had higher mortality rates in women and higher incidence rates in a wider range of regions.
Temporal trend analysis showed that mortality rates continued to decline at varying rates, with the fastest decline occurring from 2018 to 2021. The incidence initially increased but began to decrease after 2010.
Additionally, analyzes of socio-economic differences showed that for both endpoints, mortality was more concentrated in low-SDI countries, while morbidity remained concentrated in high-SDI countries.
Decomposition analysis showed that epidemiological changes accounted for most of the decrease in estimated deaths, while demographic factors, particularly population growth, accounted for most of the increase in cases. Frontier analysis showed significant cross-country differences in the gap between observed and modeled frontier rates, but we were unable to directly establish their causes.
Research limitations
Because this estimate is based on disparate national data sources, the burden may be underestimated in countries with limited surveillance due to underdiagnosis, misclassification, and underreporting.
The study also combined Crohn’s disease and ulcerative colitis, used only two broad age groups, and lacked individual exposure and treatment data, making causal inferences impossible. It did not directly assess growth failure, mental health, quality of life, or other long-term clinical outcomes related to pediatric IBD.
conclusion
This study showed that the global burden of EO-IBD has changed significantly over the past 30 years. While mortality rates and disability-adjusted life-years decreased markedly, global ASIR showed little net change, yet the estimated number of affected and prevalent cases increased globally, resulting in an increase in the population of children living with the disease.
Socioeconomic patterns suggest that potential inequalities in diagnosis, access to treatment, surveillance, and health care capacity may contribute to the observed regional differences.
The findings support strengthening pediatric health care alongside targeted health policies and improved disease monitoring, especially in areas with limited diagnostic and surveillance capacity.
Further research is needed to understand why such global differences exist.
