A recent study found a link between nighttime light pollution and an elevated risk of Alzheimer's disease.

Researchers in the United States have discovered a link between the prevalence of Alzheimer's disease and nighttime light pollution.

In a paper published on Friday in Frontiers in Neuroscience, researchers Robin Voigt, Bichun Ouyang, and Ali Keshavarzian of Rush University Medical Center in Chicago stated that exposure to artificial light at night is one environmental element that may influence Alzheimer's disease.

The illness

The most prevalent kind of dementia, which is an all-encompassing term for a number of illnesses involving the loss of cognitive function, is Alzheimer's disease. It involves the buildup of plaques and tangles in the brain as well as the premature aging of certain neurons that are involved in memory processing and storage.

Forgetfulness is one of the early symptoms; as the condition worsens, patients experience confusion, lose their way in familiar areas, and struggle to plan and finish basic tasks.

Estimates from the WHO for 2023 state that over 55 million individuals globally have dementia, with Alzheimer's accounting for over 75% of these cases. It is estimated that between 3 and 9 million Indians are afflicted with the illness; this figure is expected to rise as India's population ages.

The most recent medications may delay cognitive aging, but a solution is still not accessible.

The research

Previous studies have indicated that a variety of factors, including genetics, illnesses, and environmental stressors, may play a role in Alzheimer's disease. By integrating a new environmental factor—light pollution—that hasn't been taken into account before, the new study advances this scholarship.

The study combined publicly accessible Medicare data reports on the frequency of Alzheimer's disease with satellite-acquired light pollution data from the US. The research included additional medical data on variables that were thought to be risk factors or were known to be so.

Researchers discovered that while nighttime light intensity was more strongly correlated with the prevalence of Alzheimer's than conditions like diabetes and hypertension, alcohol abuse, chronic kidney disease, depression, heart failure, and obesity—all frequently mentioned risk factors—was more strongly correlated with the disease.

For individuals with early-onset Alzheimer's disease, especially those under 65, the relationship between light exposure and the disease was even more pronounced.

One of the study's authors, Robin Voigt, told The Guardian that nighttime light exposure throws off people's circadian rhythms and impairs their ability to sleep, which increases their risk of developing the illness. Furthermore, the report notes that "disruption of circadian rhythms is associated with increased risk of diseases that are risk factors for Alzheimer's, including obesity, diabetes, and depression."

Overexposure to light

Up to 80% of people on the planet live in areas affected by light pollution.

While most people consider these artificial nighttime lights to be innocuous, and occasionally even helpful (for safety, etc.), recent studies have revealed a number of detrimental effects that these lights have on both people and the environment. The most recent study adds to the expanding body of knowledge on the topic and brings up a point that policymakers ought to be concerned about but aren't at the moment. ENS