Aging population, better survival drive projected rise in ALS cases
New analysis forecasts a 25% global increase in ALS prevalence by 2040
Because the global population is aging and people with amyotrophic lateral sclerosis (ALS) are living longer, the number of people with the disease is expected to rise by about 25% across multiple nations by 2040, according to a new study.
In the U.S., nearly 9,000 more people are expected to be living with ALS in 2040 compared with 2024, and new treatments that extend survival could raise that number even more.
“These findings suggest that ALS, which is generally classified as a rare disease, will affect an increasingly larger share of the population worldwide in the coming decades, with important implications for health care planning, resource allocation, and research prioritization,” Rosario Vasta, MD, an assistant professor at the University of Turin, in Italy, and the study’s first author, said in a press release.
The study, “Amyotrophic Lateral Sclerosis Prevalence Projection in 2040: A Less Rare Disease,” was published in the Annals of Clinical and Translational Neurology. The study was co-authored and funded by the ALS Association.
Why tracking ALS prevalence matters for care and public health
Accurately determining disease prevalence — the number of people living with the condition at a given point in time — and understanding how it may change over time is essential.
In clinical practice, it helps doctors assess which conditions are more or less likely when diagnosing patients. For public health officials, prevalence data help guide decisions on where to focus resources and which programs may provide the greatest benefit.
As the population ages and people with ALS live longer, the number of individuals with the condition is likely to increase. Prevalence may also climb faster in some countries than others because access to treatments and services can vary.
“More people are gaining access to multidisciplinary care, which we know extends survival and improves quality of life,” said Kuldip Dave, PhD, senior vice president of research at the ALS Association and a study co-author. “Greater awareness is also helping people be diagnosed with ALS earlier and begin treatment with appropriate approved therapies as soon as possible, when they are more likely to provide benefit.”
To better understand how ALS prevalence may change over time, researchers examined data from the Piemonte and Valle d’Aosta ALS Register (PARALS), a long-standing ALS registry that has tracked patients in two Italian regions since 1995, to assess historical trends.
Between 1995 and 2019, 3,294 people were diagnosed with ALS in Piemonte and Valle d’Aosta. From 2005 to 2019, the incidence, or the number of new ALS cases per year, ranged from 3.21 to 3.61 per 100,000 people, and the median survival time increased from 2.47 to 3.42 years.
Consistent with increasing incidence and longer survival, ALS prevalence also rose — from 7.92 per 100,000 in 2005 to 10.55 per 100,000 in 2019.
Study projects how ALS cases may rise through 2040
The researchers then estimated ALS prevalence for each future year up to 2040, assuming that incidence and survival rates would increase at a similar pace seen in previous years.
In Piemonte and Valle d’Aosta, if the same historical annual increase was applied up to 2040, the median survival is expected to reach 4.67 years by 2040, and the incidence rate is expected to reach 3.82 per 100,000. The ALS prevalence in this region is anticipated to reach 15.72 per 100,000 people by 2040.
Researchers noted the Italian population is projected to decline by the end of 2040, largely because of fewer younger people and an increase in older adults. Even so, the ALS incidence rate is expected to rise across Italy between 2019 and 2040 (3.01 vs. 3.78 per 100,000). Applying the same survival gains seen in the PARALS, ALS prevalence in Italy is projected to reach 15.91 per 100,000 by 2040.
In the U.S., the prevalence of ALS is expected to rise from 9.68 per 100,000 in 2024 to 11.21 in 2040, representing 8,778 more people living with ALS. When the researchers applied an estimated six-month survival benefit from Radicava (edaravone), an ALS therapy approved to slow disease progression, the ALS prevalence increased further to 12.01 per 100,000.
Greater awareness is also helping people be diagnosed with ALS earlier and begin treatment with appropriate approved therapies as soon as possible, when they are more likely to provide benefit.
In Japan, the prevalence of ALS was 9.9 per 100,000 in 2009 and is projected to reach 14.18 by 2040. When factoring in Radicava treatment, the prevalence in Japan could rise to 15.32 per 100,000 people.
Overall, the prevalence of ALS is expected to increase by 2040 across all countries studied, including Ireland, Scotland, Norway, Malta, Israel, South Korea, Austria, and China.
Nevertheless, the impact will vary depending on the population size. China, with its large population, for example, is expected to have one of the highest increases in ALS prevalence (42.7%), which translates to 21,995 more patients from 2024 to 2040.
Researchers have also developed a free online tool called PrEALS, which enables users to examine how changes in survival, incidence, demographics, and other factors may influence regional prevalence rates.
“Public health policies should promptly allocate resources to ensure these patients receive the necessary care until a cure is found,” the team concluded. “We provide a framework to help model those increases and the impacts of changes in survival.”
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