Science speaks: for some time now, different researchers have been trying to verify whether there is a relationship between the quality of the air we breathe and brain function. If we already know very well that pollution clearly affects the health of our lungs and respiratory tract, now the scientific community goes one step further, extending these dire consequences to mental health.
A study published in February in the journal JAMA Network Open has found evidence that long-term exposure to high levels of air pollution increases the risk of depression in older people. To reach this conclusion, they collected the data of approximately nine million people enrolled in Medicare, the US state health insurance plan in which people over 64 years of age can be found.
The researchers are clear about it and these are their words: “Thanks to this study, harmful associations between long-term exposure to high levels of air pollution and an increased risk of depression diagnosis in old age have been observed. In addition, we have to add factors such as social stress to pollution”.
The polluted air to which the study participants (and therefore the rest of the population) have been exposed for years contained dust and smoke, nitrogen dioxide from traffic and ozone, which is expelled, in addition to cars, power plants and part of the country's industrial sector.
However, researchers have not yet determined exactly what changes in the brain to make it more prone to depression. One of the theories that they handle is that of inflammation of the brain. Such inflammation can negatively affect neurons and different parts of the brain, such as the prefrontal cortex and the hippocampus. These two areas are closely linked to depression and Alzheimer's disease.
As expected, pollution and its dire consequences for health affect people with a low socioeconomic level more. This is because many of the sources of pollution, such as factories, refineries, and power plants, are in urban areas where the population is densest and housing is cheapest. Also, many low-income people work in the most polluting industry, such as construction, mining, or manufacturing.