Research highlights how the sound of gunshots at night can disrupt sleep, particularly in America’s urban areas, with low-income communities bearing the brunt of the impact.

Summary: A study found that gunshots are twice as likely to occur at night, disproportionately affecting low-income communities in the US and potentially disrupting sleep due to the noise and subsequent emergency response sirens. Analyzing over 72,000 records from six major cities, the research estimated 12.5 million person nights of potential sleep disruption annually. The study, emphasizing the social determinant of sleep and population health, plans further investigation into sleep disturbances caused by nighttime gunshots to develop community-based interventions for affected areas.

Key Takeaways:

  • Researchers from Mass General Brigham analyzed timing and location of gunshots in six of the most populated US cities (Baltimore, Boston, Washington DC, New York, Philadelphia, and Portland, Ore) from 2015 to 2021.
  • The team estimates that, annually, approximately 12.5 million person-nights—the number of nights of gunshots multiplied by the number of people in earshot—are impacted by nighttime gunshots and that those were more common in low-income areas in each city.
  • The noise of nighttime gunshots may have underrecognized and underappreciated effects on sleep and health for people living in surrounding communities.

The crack of a gunshot ringing out in the night is all too familiar to many Americans. A new study captures just how common—and potentially disruptive—nighttime gunshots can be in American cities. 

In a cross-institutional collaboration from Mass General Brigham’s founding members, Brigham and Women’s Hospital and Massachusetts General Hospital, researchers examined the number of nights and people potentially affected by the sound of nighttime versus daytime gunshots and the relationship between the sound of nighttime gunshots and median household income in the United States. 

Impact on Sleep and Community Health

The team found gunshots are twice as likely to occur at night and that low-income communities are disproportionately affected by them. Their results are published in the Journal of General Internal Medicine.

Photo 184351045 © Daniel Tadevosyan |

“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,” says corresponding author Rebecca Robbins, MMSc, PhD, MS, of the Division of Sleep and Circadian Disorders at Brigham and Women’s Hospital, in a release. “The findings from our study shed light on this potentially significant and underexplored social determinant of sleep and population health.” 

Minimizing disruptions during the sleep cycle is critical to achieving quality sleep and improving overall health. Various factors, including jetlag from traveling or the onset of hunger during the late hours of the night, can interrupt sleep and lead to metabolic, cardiovascular, and mental health diseases and conditions. Other disruptions, such as nighttime gunshots, warrant further exploration.

Study Insights and Data Analysis

The current study focuses on the impact of the sounds of guns on surrounding communities; previous studies from the authors have focused on mental and behavioral health consequences from gun violence. 

“The traumatic ripple effects from gunshots can extend across families and entire says. Our work helps to broaden how we think about who is impacted by these events,” says co-last author Chana A. Sacks, MD, MPH, of the Division of General Internal Medicine and Mongan Institute at Massachusetts General Hospital, in a release.

The team gathered 72,236 publicly available records on the time and location of gunshots in six major cities in the United States, including Baltimore, Boston, Washington DC, New York, Philadelphia, and Portland, Ore., from 2015 to 2021. 

Disproportionate Effects and Income Disparities

Using those data, investigators compared the prevalence of gunshots during the day versus the night. In addition, they created maps to visualize nighttime gunshot density across the cities. To identify communities potentially impacted by the sound of the gunshot, they estimated the number of those residing near to the location where gunshots took place. The team also examined the association between the number of nighttime gunshots and median household income. 

Photo 301628446 © Kinomaster |

To measure the potential effect of the sound of nighttime gunshots, the team estimated the number of individuals within earshot and the number of nights of potentially disrupted sleep for all individuals within hearing range. The team defined this metric as “person nights” and estimated that approximately 12.5 million person nights across the six cities could be impacted annually.

Among the findings was that as median household income went up, rates of nighttime gunshots went down. This highlighted a higher level of gunshot impact—and resulting potential sleep and other disruptions—for people living in low-income neighborhoods. Additionally, it was discovered that 51,789 (72%) of the gunshots occurred during the nighttime across all six cities, with most of them occurring on Saturday and Sunday nights.

Future Directions and Collaborative Efforts

The authors note that they did not directly measure sleep disruptions as part of this study. Only six of the 30 most populated cities in the US had enough publicly available data to be included in the analysis. 

The research team plans to study sleep disturbances in response to nighttime gunshots as they work to design community-based sleep interventions to support individuals in communities with high incidences. The authors credit their collaboration across hospitals and across areas of research expertise for the insights described in their paper.

“Working as a multidisciplinary research team across the Mass General Brigham healthcare system, with experts in sleep and gun violence, we have been able to advance our understanding of the impacts that gunshots have on communities and inform this critical national conversation,” said Robbins in a 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.”

Photo 124167301 © Marcos Calvo Mesa |