MDA 2026: Wildfire smoke exposure raises risks for ALS patients
Exposure before disease onset may double respiratory risk
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- Wildfire smoke exposure before ALS onset doubles the risk of respiratory failure or death.
- This increased risk is consistent across all age groups.
- Further research is needed to develop environmental guidelines for ALS.
People with amyotrophic lateral sclerosis (ALS) who were exposed to smoke from wildfires prior to developing the disease are more than twice as likely to experience respiratory failure or death, according to a new analysis.
The findings underscore the need for further research to understand how air pollution and climate change will affect ALS patients and to develop environmental guidelines for the ALS community, the study’s author said.
The results were detailed in a poster, “Presymptomatic Wildfire Smoke Exposure Doubles Risk of Respiratory Failure or Death among MOVR ALS Participants,” presented at the Muscular Dystrophy Association (MDA) Clinical & Scientific Conference 2026, held March 8-11 in Orlando, Florida, and online.
ALS is a neurological disorder that causes muscle weakness and eventual paralysis. The disease is fatal, most commonly due to respiratory failure that occurs when chest muscles become too weak for a person to keep breathing. Exposure to air pollution has a host of well-documented negative health consequences. In ALS, several studies have reported that exposure to air pollution is associated with a higher risk of developing the disease and worse outcomes for patients.
Climate change has increased the frequency and intensity of wildfires in recent years. Smoke from wildfires may pose a major health risk, but the impact of wildfire smoke on ALS patients has not been studied.
Database analysis shows respiratory risk rises with exposure
Jill Goslinga, MD, an assistant professor at the University of California San Francisco, conducted an analysis of data from MOVR, an MDA database that tracks outcomes from people with ALS and other neuromuscular disorders.
Goslinga’s analysis covered data from 2,296 people with ALS who participated in MOVR from 2013 to 2023. Over an average follow-up time of more than two years, 9.3% of patients either died or developed respiratory failure.
Based on documented history of wildfire smoke exposure, the patients were divided into four groups, ranging from the least smoke exposure to the most.
Statistical analyses showed that, compared with the group exposed to fewer smoke days in the five years before ALS symptom onset, the risk of respiratory failure or death was more than double in the three groups with higher smoke day exposure.
This effect was consistent across all age groups, and a similar effect was observed when the total exposure to wildfire smoke in the five years before symptom onset was assessed.
“Wildfire smoke exposure prior to ALS onset is associated with approximately double the adjusted hazards of respiratory failure and death among MOVR ALS participants, with an apparent threshold effect above the lowest exposure quartile,” Goslinga wrote in the poster.
She noted several limitations in the analysis. She wasn’t able to fully account for key factors such as smoking status and sociodemographic characteristics, and the analysis provides limited insight into the relative effects of wildfire smoke compared with other forms of air pollution.
“Further research is urgently needed to better characterize the impact of distinct air pollution sources on respiratory outcomes and survival in ALS and to develop evidence-based environmental guidelines for the ALS community,” Goslinga wrote.
Note: The ALS News Today team is providing live coverage of the 2026 MDA Clinical & Scientific Conference March 8-11 in Orlando, Florida. Go here to see the latest stories from the conference.
