Living near waterbodies as a proxy of cyanobacteria exposure and risk of amyotrophic lateral sclerosis: a population based case-control study

Environ Res. 2020 Jul:186:109530. doi: 10.1016/j.envres.2020.109530. Epub 2020 Apr 15.

Abstract

Background: Epidemiological studies highlighted the possibility that exposure to cyanotoxins leads to the development of the neurodegenerative disease amyotrophic lateral sclerosis (ALS).

Methods: We devised a population-based case-control study in two Italian populations. We used residential proximity of the residence to water bodies as a measure of possible exposure to cyanotoxins.

Results: Based on 703 newly-diagnosed ALS cases and 2737 controls, we calculated an ALS odds ratio (OR) of 1.41 (95% CI: 0.72-2.74) for current residence in the vicinity of water bodies, and a slightly lower estimate for historical residence (OR: 1.31; 95% CI: 0.57-2.99). Subjects <65 years and people living in the Northern Italy province of Modena had higher ORs, especially when historical residence was considered.

Conclusions: Overall, despite some risk of bias due to exposure misclassification and unmeasured confounding, our results appear to support the hypothesis that cyanotoxin exposure may increase ALS risk.

Keywords: Amyotrophic lateral sclerosis; Case-control study; Cyanotoxins; Epidemiology; Risk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amyotrophic Lateral Sclerosis* / chemically induced
  • Amyotrophic Lateral Sclerosis* / epidemiology
  • Case-Control Studies
  • Cyanobacteria*
  • Humans
  • Italy / epidemiology
  • Neurodegenerative Diseases*
  • Risk Factors