The two professions associated with the lowest levels of death due to Alzheimer’s disease may be surprising.
Taxi and ambulance drivers were found to have the lowest proportion of deaths of more than 440 occupations that were considered in a new observation-based study from Massachusetts physicians.
Alzheimer’s disease is a type of dementia that affects memory, thinking, and behavior. It impacts millions of Americans and is one of the top 10 causes of death in the US.
While the study’s findings cannot confirm a direct link between the professions and reduced risk, its researchers said they raise the possibility that memory-intensive driving occupations could be associated with some protection.
“We view these findings not as conclusive, but as hypothesis-generating,” they said, noting that no resolute conclusions can be drawn about cause and effect.
The research was published Monday in the Christmas issue of the journal The BMJ.
The jobs require frequent spatial and navigational processing: the ability to sense and incorporate information about the location of objects around them.
Although, the trend was not seen in other related jobs, like driving a bus or piloting an aircraft. It was also not seen in other forms of dementia, which suggests changes in the hippocampus region of the brain — which is used for spatial memory and navigation — may account for the reduction.
The hippocampus, located deep within the brain, has been shown to be enhanced in London taxi drivers compared to the general population.
The region is also one of the parts of the brain involved in the development of Alzheimer’s disease.
The study’s authors examined death certificates for adults between January 2020 and the last day of December 2022.
Of the 16,658 taxi drivers, just 171 died from Alzheimer’s. Of the 1,348 ambulance drivers, 10 deaths were from the disease.
Across the general population, the proportion of deaths from Alzheimer’s was 1.69 percent, while the proportion for taxi and ambulance drivers was 1.03 percent and 0.91 percent, respectively.
The authors acknowledged that there were limitations, including that individuals who are at higher risk of developing Alzheimer’s disease may be less likely to enter driving occupations. However, they said this is unlikely because disease symptoms typically develop after working age.
“Further research is necessary to definitively conclude whether the spatial cognitive work required for these occupations affects the risk of death from Alzheimer’s disease and whether any cognitive activities can be potentially preventive,” they said.