High levels of metals in the blood and urine may be linked to an increased risk of developing and dying from amyotrophic lateral sclerosis (ALS), according to a new study led by the University of Michigan.
ALS is a rare and fatal neurodegenerative disease that has been linked to both genetic and environmental factors, including exposure to pesticides and metals. This latest study looked at the levels of metals in the blood and urine of individuals with and without ALS and found that exposure to various metals, either individually or in combination, was associated with a higher risk of developing ALS and a shorter survival time.
The findings of this study were published in the prestigious Journal of Neurology, Neurosurgery, and Psychiatry.
Dr. Stephen Goutman, the senior author of the study, emphasizes the importance of understanding the role of metal exposure in the development of ALS in order to improve prevention and treatment strategies for the disease. Previous epidemiological studies have suggested a connection between metal exposure and ALS risk, but it is crucial to delve deeper into how different metals and combinations of metals impact the risk and survival of ALS.
The research team analyzed metal levels in plasma and urine samples from over 450 individuals with ALS and nearly 300 individuals without the disease. They found that higher levels of metals such as copper, selenium, and zinc were associated with an increased risk of ALS and earlier mortality.
Using these findings, the researchers developed environmental ALS risk scores that revealed a three-fold increase in risk associated with mixtures of metals in plasma and urine. Interestingly, incorporating an ALS polygenic risk score, which accounts for genetic factors, did not change the relationship between metal exposure and ALS risk or survival.
Dr. Kelly Bakulski, a co-author of the study, highlights the complexity of interactions between genetic and environmental factors in influencing disease risk and progression. Future research may uncover additional genetic factors that play a role in ALS risk and how the body metabolizes metals.
The study also identified a higher level of metal mixtures in the blood and urine of participants who had occupations with a greater risk of metal exposure. This aligns with a previous study from the research team that found individuals with ALS reported increased occupational exposure to metals before diagnosis.
Dr. Dae Gyu Jang, the first author of the study, stresses the importance of considering occupational and environmental factors when evaluating an individual’s overall exposure risk to metals. By avoiding activities that involve high levels of metal exposure, individuals may be able to reduce their risk of developing ALS.
Dr. Goutman indicates that future research will focus on identifying the specific metal exposures that have the strongest associations with ALS and their implications on the disease. Funding for this study was provided by several organizations, including the National Institute of Neurological Disorders and Stroke, the National Institute of Environmental Health Sciences, the Centers for Disease Control and Prevention, and the ALS Association.
Overall, this study sheds light on the potential role of metal exposure in the development and progression of ALS and underscores the importance of considering both genetic and environmental factors in understanding the disease. By identifying and mitigating exposure to certain metals, we may be able to reduce the risk of ALS and improve outcomes for individuals living with this devastating condition.
