Taxi and ambulance drivers, whose work requires frequent spatial and navigational processing, have the lowest number of deaths from Alzheimer’s disease compared to other professions, a study in the Christmas issue of The BMJ.
The findings are observational and so cannot confirm a direct link, but the researchers say they raise the possibility that memory-intensive driving occupations, such as taxi and ambulance driving, may be associated with some protection against Alzheimer’s disease.
The hippocampus is a brain region used for spatial memory and navigation and has been shown to be improved in taxi drivers in London compared to the general population.
It is also one of the brain regions involved in the development of Alzheimer’s disease, raising the possibility that occupations that require frequent spatial processing may be associated with reduced mortality from Alzheimer’s disease.
To investigate this, a team of US researchers analyzed death certificates for adults from 443 different occupations between January 1, 2020 and December 31, 2022. The data included cause of death, usual occupation (in which the deceased spent most of their working life ) and sociodemographic data. information (e.g. age, gender, race, ethnic group and education level).
Of the nearly 9 million people who died with occupational information, 3.9% (348,328) had Alzheimer’s disease listed as the cause of death. Of the 16,658 taxi drivers, 171 (1.03%) died of Alzheimer’s disease, while this was 0.74% among ambulance drivers (10 of 1,348).
After adjusting for age at death and other sociodemographic factors, taxi and ambulance drivers had the lowest rate of deaths from Alzheimer’s disease of all occupations studied (1.03% and 0.91% respectively) and compared to the general population (1 .69%).
The researchers note that this trend was not observed in other transportation-related jobs, such as bus drivers or airline pilots (possibly due to their reliance on predetermined routes) or in other forms of dementia, suggesting that neurological changes in the hippocampus or elsewhere may be associated with taxi operators and ambulance drivers may be responsible for reducing the risk of Alzheimer’s.
This is an observational study, so no firm conclusions can be drawn about cause and effect. And the authors acknowledge several limitations, including that individuals at higher risk for developing Alzheimer’s disease may be less likely to enter or maintain memory-intensive lanes such as taxi and ambulance driving. However, they say this is unlikely as symptoms of Alzheimer’s disease typically develop after working age.
“We do not view these findings as conclusive, but as hypothesis generating,” they say.
“Further research is needed to definitively conclude whether the spatial cognitive work required by these occupations influences the risk of death from Alzheimer’s disease and whether cognitive activities have the potential to be preventive.”