THURSDAY, April 4, 2024 -- A good night's sleep is often hampered by caffeine, hunger, alcohol or chronic pain.

Now, America has a new cause of poor sleep: the sound of gunfire on city streets.

New research shows that gunshots are twice as likely to occur at night, mostly affecting the sleep of people in low-income neighborhoods.

In fact, nearly three out of four gunshots (72%) occur at night in major U.S. cities, mostly on Saturday and Sunday, researchers found.

“A nighttime gunshot likely disrupts the sleep of nearby community residents due to the sheer sound of the shot, which is then followed by a cacophony of sirens from police vehicles and ambulances,” said researcher Rebecca Robbins, an assistant professor of sleep medicine at Brigham and Women’s Hospital in Boston.

For the study, researchers analyzed more than 72,000 records on the time and location of gunshots in six major cities around the United States, including Baltimore, Boston, New York, Philadelphia, Portland, Ore., and Washington, D.C., between 2015 and 2021.

The team tracked how many gunshots occurred during the day versus at night, and then created maps to show which neighborhoods are most plagued by nighttime gunfire. They also estimated the number of people who lived near a location where gunshots occurred.

As many as 12.5 million nights of sleep were ruined by gunfire across the six cities, given the number of people living near these incidents, researchers projected.

They also found that as average income increased in a neighborhood, the rate of nighttime gunshots decreased.

The new study was published April 2 in the Journal of General Internal Medicine.

Researchers noted that they couldn’t directly measure sleep disruptions based on this data, and could only estimate how many happened.

Further, only six of the 30 most populated cities in the United States had enough publicly available data for the researchers to hazard an estimate.

“With experts in sleep and gun violence, we have been able to advance our understanding of the impacts that gunshots have on communities,” Robbins said in a hospital news release. “Conversations about guns often focus on the statistics on gun-related deaths, but our work draws attention to some of the less discussed impacts of gun violence.”

More information

Harvard Medical School has more on reasons for poor sleep.

SOURCE: Mass General Brigham, news release, April 3, 2024