The aging of the world’s population along with improved survival rates will cause the number of people living with amyotrophic lateral sclerosis (ALS) to rise sharply over the next 15 years, according to a new study published in Annals of Clinical and Transitional Neurology.
The study — Amyotrophic Lateral Sclerosis Prevalence Projection in 2040: A Less Rare Disease — was co-authored and funded by the ALS Association. The research was published in October 2025.
“Prevalence of the disease is projected to increase by 25% across multiple countries worldwide by 2040,” the ALS Association said in a Nov. 5 announcement. “Advances in ALS treatment would push that number even higher.”
Data for the study was taken from registries for the Piemonte and Valle d’Aosta region of Italy from 2005 to 2019.
Researchers projected survival trends into the future based on trends observed during that 2005 to 2019 period, and also factored in population projections. The data came from nearly 3,300 patients with ALS.
“We determined that ALS survival increased by 0.06 years annually from 2005 to 2019 in Piemonte and Valle d’Aosta,” the authors said in the study. “Considering changes in incidence due to population aging, the prevalence is projected to reach 15.72 per 100,000 population by 2040 in this area, while rising by a median of 24.9% across multiple countries worldwide. If a new drug could provide a six-month increase in survival starting in 2025, disease prevalence would rise by 37.8% by 2040.”
Knowing the frequency of ALS and predicting its possible changes, the authors added, “is crucial for several reasons. In clinical practice, it impacts the differential diagnosis, making rare diseases less probable to be encountered. In public health, it guides the allocation of resources and helps understand the potential impact of one initiative over another.”
The incidence rate of ALS over time, the study said, is likely being caused by “an improved recognition of ALS cases, especially among older individuals,” as well as including “more subtle phenotypes” in ALS statistics, such as possible ALS and frontotemporal dementia-ALS.
The segment of people worldwide who are older than 60 “is anticipated to increase more rapidly than other age groups,” the study said. “ALS mainly affects older individuals, with symptoms typically manifesting around the age of 65. Consequently, the number of new ALS cases is projected to rise faster than the general population, leading to an increase in ALS incidence.”
The study pointed out a result that initially sounds counter-intuitive: As ALS treatments and support improve, the number of ALS patients will actually grow.
Authors confirmed that ALS survival improved from 2005 to 2019, which caused ALS’s prevalence to rise from 7.92 to 10.55 per 100,000 people in that same time period.
By 2040, authors estimated that ALS prevalence will reach 15.72 per 100,000 people. The number of ALS patients in Europe is predicted to increase 20% in Europe and 34% in the United States from 2015 to 2040.
“These estimates are likely conservative, as patient survival has improved over time,” the study noted.
As support for ALS patients grows and improves — authors recommended that “more ALS tertiary centers should be established and equipped across national territories” — those interventions “will, in turn, likely contribute to improving patient survival, further increasing the absolute number of individuals living with ALS at any given time.”
