According to a study published recently in the medical journal Alzheimer’s & Dementia, long-term exposure to noise in certain communities may relate to cognitive decline in older adults and could increase risk of full-blown dementia.
Researchers tested cognitive markers — memory, language command, spatial reasoning — for 5,000 seniors aged 65 or older, after five years of studying the environs where these people lived. That involved recording the average daytime decibel levels of each community, which ranged from 51 to 78 decibels. The spectrum included all sorts of homes, from peaceful suburban blocks to apartment complexes next door to the interstate.
Their findings? Each 10 decibel increase in community noise level was associated with a 36 percent higher likelihood of mild cognitive impairment. An uptick in noise also accounted for 29 percent increased risk of Alzheimer’s disease. These conclusions came to light even after controlling for external factors like education, race, smoking, alcohol consumption, and neighborhood air pollution levels.
The researchers plan to continue studying the connection between community noise and cognitive decline — at this point, they can’t say for certain why there’s a link at all — but at least one professor pointed to sleep deprivation, hearing loss, and elevated blood pressure as the natural endgames to days filled with noise. Historically, each increases risk for dementia. Unsurprisingly, the strongest associations were discovered in the study’s poorest neighborhoods, where overcrowding and urban sprawl are common.