Research shows taxi and ambulance drivers have lowest Alzheimer’s death rates

By Stephen Beech

Alzheimer’s disease deaths are lowest among taxi and ambulance drivers, reveals new research.

The findings suggest that frequent spatial and navigational processing tasks - which professional drivers need to perform compared with other occupations - might offer some protection against dementia, say scientists.

The American study, published in the Christmas issue of The BMJ, was observational, so the researchers cautioned that it can’t confirm a direct link.

But they say it raises the possibility that memory-intensive motoring occupations, such as taxi and ambulance driving, might be associated with some protection against Alzheimer’s disease.

The hippocampus is a brain region used for spatial memory and navigation and has been previously shown to be enhanced in London taxi drivers compared with the general population.

It is also one of the brain regions involved in the development of Alzheimer’s, raising the possibility that occupations that involve frequent spatial processing tasks may lower the possibility of dying from the debilitating disease.

The American research team analyzed death certificates for adults from 443 different occupations between January 1, 2020, and December 31, 2022.

Data included cause of death, usual occupation, and other information such as age, race and educational attainment.

Of nearly nine million people who had died with occupational information, 3.9% had Alzheimer’s listed as a cause of death.

Among 16,658 taxi drivers, 171 (1.03%) died from Alzheimer’s disease, while among ambulance drivers, the rate was 0.74% (10 of 1,348).

After adjusting for age at death and other factors, taxi and ambulance drivers had the lowest proportion of deaths from Alzheimer’s disease of all occupations examined and compared with the general population (1.69%).

The researchers note that the trend was not seen in other transport-related jobs such as bus drivers (3.1%) or aircraft pilots (4.5%), possibly due to their reliance on predetermined routes, or with other forms of dementia.

They say that neurological changes in the hippocampus or elsewhere amongst taxi and ambulance drivers may account for the reduction in Alzheimer’s risk.

Study lead author Dr. Vishal Patel, a resident physician at Brigham and Women’s Hospital in Boston, Massachusetts, said: “The same part of the brain that’s involved in creating cognitive spatial maps - which we use to navigate the world around us - is also involved in the development of Alzheimer’s disease.

“We hypothesized that occupations such as taxi driving and ambulance driving, which demand real-time spatial and navigational processing, might be associated with a reduced burden of Alzheimer’s disease mortality compared with other occupations.”

Senior study author Professor Anupam Jena, a physician at Massachusetts General Hospital, said: “Our results highlight the possibility that neurological changes in the hippocampus or elsewhere among taxi and ambulance drivers may account for the lower rates of Alzheimer’s disease.

"We view these findings not as conclusive, but as hypothesis-generating.

“But they suggest that it’s important to consider how occupations may affect risk of death from Alzheimer’s disease and whether any cognitive activities can be potentially preventive.”

He added: “Further research is necessary to definitively conclude whether the spatial cognitive work required for these occupations affect risk of death from Alzheimer’s disease and whether any cognitive activities can be potentially preventive.”