ALS is a progressive neurological disease that attacks the nerves that interact with the body’s muscles. The disease usually leads to complete paralysis of the body, depriving patients of the ability to walk, talk, eat and breathe.
The researchers studied ALS patients and healthy elderly volunteers living in Malta who participated in an ongoing study aimed at identifying genetic and environmental risk factors. Malta is a sovereign micro-state in the middle of the Mediterranean Sea and is home to a geographically and culturally isolated population. It has recently been established that Maltese ALS patients have a unique genetic structure compared to their European counterparts.
In this study, based on demographic data collected over a four-year period, the researchers found that manual workers were twice as likely to develop ALS. In fact, close to two-thirds of patients with ALS reported working with a blue collar as a major occupation throughout their careers.
We have long known that Italian footballers, players of the American National Football League and military soldiers have an increased risk of ALS compared to the general population. The common thread that runs through these professions is continuous or strenuous physical exertion. Our research supports this notion. “
Dr Ruben J. Cauchi, lead researcher of the study, senior lecturer at the Medical Faculty of the University of Malta and lead researcher at the Center for Molecular Medicine and Biobanking of the University of Malta
Despite the fact that Malta has no professional footballers or elite military service, the study showed that jobs that cause sweat, including those in construction and carpentry, are associated with a higher risk of ALS. Patients in these occupations were more likely to develop ALS with a bulbar attack, a form of the disease in which speech or swallowing problems occur before the muscles in the limbs weaken. Patients with ALS with a bulbar attack fare worse than those with the onset of limbs.
The establishment of a national register of ALS and Biobank at the University of Malta in 2017, with the aim of identifying and monitoring ALS patients and healthy volunteers, was key to this discovery. Currently, the research team is studying the interrelationship of genetics and environmental exposure in causing ALS in patients.
Wismayer, MF, and others. (2021) Occupational risk and amyotrophic lateral sclerosis: a case study and control in an isolated island population of Malta. Amyotrophic lateral sclerosis and frontotemporal degeneration. doi.org/10.1080/21678421.2021.1905847.