Global Burden of Mild Traumatic Brain Injury: 1990-2019

Academic Background

Mild traumatic brain injury (MTBI) is a common global health issue, particularly prevalent among the elderly population. MTBI not only causes symptoms such as headaches, dizziness, and fatigue but may also lead to long-term cognitive impairments, mood swings, and sleep disorders, significantly affecting patients’ quality of life. Although MTBI constitutes the majority of traumatic brain injuries (TBI), it receives less attention in the medical field compared to severe TBI. However, the contribution of MTBI to the global disease burden cannot be overlooked, especially in low-income countries and among the elderly. To better prevent and manage MTBI, understanding its epidemiological characteristics and global burden is crucial.

This study aims to utilize data from the Global Burden of Disease Study (GBD) 2019 to analyze the trends in the incidence, prevalence, and years lived with disability (YLDs) of MTBI at the global, regional, and national levels from 1990 to 2019. It also explores the underlying causes to provide a scientific basis for developing effective intervention strategies.

Source of the Paper

This paper was co-authored by Liang Wu, Yunfei Li, Meng Sun, Pengpeng Ye, Zhaofeng Zhang, and Weiming Liu, affiliated with institutions such as the Department of Neurosurgery at Beijing Tiantan Hospital, the Department of Nutrition and Food Hygiene at Peking University School of Public Health, and the National Center for Non-Communicable Disease Control and Prevention at the Chinese Center for Disease Control and Prevention. The paper was published online on June 24, 2024, in the International Journal of Surgery.

Research Process

Data Sources and Analytical Methods

The study data were sourced from the GBD 2019 Global Health Data Exchange Tool (GBD Results Tool), covering MTBI burden data from 204 countries and territories between 1990 and 2019. GBD 2019 employed standardized methods to comprehensively assess health loss associated with 369 diseases and 87 risk factors. The study used three main tools for data analysis: the Cause of Death Ensemble Model (Codem), Spatiotemporal Gaussian Process Regression (ST-GPR), and Dismod-MR (a Bayesian meta-regression tool).

Research Steps

1. Data Extraction and Preprocessing: MTBI incidence, prevalence, and YLDs data were extracted from the GBD 2019 database and categorized by age, sex, geographic location, and Sociodemographic Index (SDI).
2. Trend Analysis: Age-standardized rates (ASRs) and estimated annual percentage changes (EAPC) were calculated to assess temporal trends in MTBI burden.
3. Age-Period-Cohort Model (APC Model): The APC model was used to analyze the age, period, and cohort effects of MTBI incidence, exploring trend differences across SDI groups.
4. Etiology Analysis: The primary causes of MTBI were analyzed, particularly the contribution of falls and road traffic injuries to the MTBI burden.
5. Gender and Age Differences: The MTBI burden was compared across different genders and age groups, with a focus on the high incidence rates among the elderly and males.

Key Findings

Global MTBI Burden

In 2019, the global number of incident MTBI cases was 12,268.5 thousand (95% uncertainty interval [UI]: 992.66–1602.07), prevalent cases were 11,482.5 thousand (95% UI: 107.59–123.52), and YLDs were 1,366.9 thousand (95% UI: 96.36–183.35). From 1990 to 2019, the age-standardized incidence, prevalence, and YLDs rates of MTBI decreased, but the absolute number of cases increased significantly.

Regional and National Differences

In 2019, the Australasian region had the highest age-standardized prevalence rate at 255.1 per 100,000 population, while Andean Latin America had the lowest at 89.1 per 100,000 population. Afghanistan, Slovenia, and Syria had the highest MTBI prevalence rates. East Asia experienced the fastest growth in prevalence, while high-income North America saw the most significant decline.

Etiology Analysis

Falls and road traffic injuries were the primary causes of MTBI. In 2019, the global number of MTBI cases attributed to falls was 4,239,200 (95% UI: 254.97–660.13), with an age-standardized incidence rate of 54.33 per 100,000 population.

Gender and Age Differences

Across all age groups, males had higher MTBI incidence, prevalence, and YLDs rates than females. The elderly population bore a significantly higher MTBI burden compared to other age groups, particularly in low-income countries.

Conclusion

Although the global age-standardized incidence, prevalence, and YLDs rates of MTBI have declined, the absolute number of cases has increased significantly, especially among the elderly and males. Falls and road traffic injuries are the primary causes of MTBI, and preventing falls and improving road traffic infrastructure are key measures to reduce the MTBI burden. Additionally, low-income countries face a heavier MTBI burden, necessitating increased investment in healthcare resources and public health education.

Research Highlights

1. Comprehensive Assessment of Global MTBI Burden: This study is the first to comprehensively assess the global incidence, prevalence, and YLDs rates of MTBI using GBD 2019 data, filling a gap in this field.
2. Application of the Age-Period-Cohort Model: The APC model revealed the age, period, and cohort effects of MTBI incidence, providing a scientific basis for targeted intervention strategies.
3. Etiology and Gender Differences Analysis: The study identified falls and road traffic injuries as the primary causes of MTBI and highlighted the reasons for higher incidence rates among males and the elderly, offering important references for public health policy formulation.

Research Significance

This study provides critical scientific evidence for the prevention and management of MTBI globally. By analyzing the epidemiological characteristics and burden trends of MTBI, the research offers targeted intervention recommendations for policymakers, healthcare systems, and social support institutions, helping to mitigate the negative impact of MTBI on global health.