Global burden of motor neuron disease: unraveling socioeconomic disparities, aging dynamics, and divergent future trajectories (1990-2040)

Abstract

Background and objectives: Motor neuron disease (MND) is a progressive neurodegenerative disorder associated with high morbidity and mortality. With global aging, the burden of MND is expected to increase, particularly in regions with rapidly aging populations. This study utilizes Global Burden of Disease (GBD) 2021 data to assess the global and regional MND burden from 1990 to 2021, examining trends by age, sex, and socio-demographic index (SDI), and projecting future trends to 2040.

Methods: Data from the GBD 2021 database for the years 1990-2021 were analyzed to evaluate age-standardized prevalence rates (ASPR), incidence rates (ASIR), mortality rates (ASMR), and disability-adjusted life years (DALYs) for MND across SDI regions, age groups, and sexes. Temporal trends were explored using joinpoint regression analysis, while future projections were generated using the Bayesian age-period-cohort (BAPC) model for 2021-2040.

Results: From 1990 to 2021, global MND prevalence increased by 68.43%, reaching 272,732 cases, while the age-standardized prevalence rate (ASPR) slightly declined, reflecting the influence of population aging. Although global incidence increased by 74.54%, the age-standardized incidence rate (ASIR) showed a modest decline, suggesting improvements in diagnostic practices. Mortality and DALY rates continued to rise globally, with high-SDI regions bearing the highest burden. Projections indicate that by 2040, global MND prevalence will decline slightly, while incidence, mortality, and DALYs will continue to rise in low- and middle-SDI regions due to aging populations.

Discussion: The global MND burden is heavily influenced by aging, particularly in high-SDI regions. Although incidence rates have slightly decreased, mortality and disability burdens are increasing, highlighting ongoing challenges in disease management and treatment. The findings stress the importance of age-targeted interventions, improving healthcare access, and addressing socio-economic disparities to mitigate the future impact of MND, particularly in low- and middle-SDI regions.

Keywords: Aging population; Future projections; Global burden of disease; Incidence; Mortality; Motor neuron disease; Socio-demographic index.

Fig. 1

Temporal trends in sex-specific age-standardized prevalence, incidence, mortality, and DALY rates of motor neuron disease across socio-demographic index regions from 1990 to 2021

Fig. 2

Global distribution of age-standardized prevalence, incidence, mortality, and disability-adjusted life years (DALYs) rates for motor neuron disease across 204 countries and territories in 2021: A age-standardized prevalence rate (ASPR); B age-standardized incidence rate (ASIR); C age-standardized mortality rate (ASMR); D age-standardized DALY rate (ASDR). Green—lowest value; yellow—highest value

Fig. 3

Age-standardized prevalence, incidence, mortality, and DALY rates of motor neuron disease in relation to SDI in 2021 among 21 GBD regions. A Age-standardized prevalence rate (ASPR); B age-standardized incidence rate (ASIR); C age-standardized mortality rate (ASMR); D age-standardized DALY rate (ASDR)

Fig. 4

Temporal trends in ASPR of MND by SDI regions: a Joinpoint regression analysis, 1990–2021. MND: motor neuron disease; ASPR: age-standardized prevalence rate; SDI, socio-demographic index; APC, annual percent change; AAPC, average annual percent change. *p < 0.05

Fig. 5

Decomposition analysis of population-level determinants of motor neuron disease prevalence, incidence, mortality, and DALYs from 1990 to 2021 across global and socio-demographic index regions. A Age-standardized prevalence rate (ASPR); B age-standardized incidence rate (ASIR); C age-standardized mortality rate (ASMR); D age-standardized DALY rate (ASDR)

Fig. 6

Projected global trends in sex-specific age-standardized prevalence, incidence, mortality, and DALY rates of motor neuron disease from 1990 to 2040. A Age-standardized prevalence rate (ASPR); B age-standardized incidence rate (ASIR); C age-standardized mortality rate (ASMR); D age-standardized DALY rate (ASDR)