Environmental and occupational risk factors of amyotrophic lateral sclerosis in Senegal

Abstract

Background: The pathophysiology of Amyotrophic lateral sclerosis (ALS) is not well known, but seems to be multifactorial. Genetic and environmental factors increase the risk of developing ALS.

Methods: We conducted case-control study from July 2015 to June 2017, comparing exposure to risk factors in 23 ALS cases and 53 controls in the department of neurology of Fann national teaching hospital in Senegal.

Results: The mean ages of cases and controls were 44.3 ± 16.3 years and 48.3 ± 17 years respectively. There was a male predominance. In the bivariate analysis, factors significantly associated to ALS were: living outside Dakar (OR: 26.6; 95% CI [5.5-127.7]), farmer profession (OR: 13.3; 95% CI [2.6-69.9]), exposure to pesticides (OR: 15.3; 95% CI [3.7-63.4]), and chemical fertilizers (OR: 5.2; 95% CI [1.7-15.4]). In multivariate analysis, living outside Dakar (OR: 16.4; 95% CI [3.2-82.8]) and exposure to pesticides (OR: 6.0; [1.3-29.1]) were identified as the main risk factors of ALS in this study.

Conclusion: We found relatively young ALS patients. This study identified significant role of living outside Dakar and exposure to pesticides. A multi-center study with a larger number of ALS patients would certainly be more accurate in determining more risk factors and their causality in ALS among African population.

French title: Facteurs de risque environnementaux et professionnels de la sclerose laterale amyotrophique au Senegal