SAN FRANCISCO — States with tight regulations on the purchase and control of guns have fewer injuries and deaths from firearms, a new study shows.

"Strict firearm legislation may help to reduce firearm-related injuries and mortalities, and help to reduce the years of life lost," Viraj Pandit, MD, a researcher at the University of Arizona in Tucson, said here at the American College of Surgeons 2014 Clinical Congress.

The number of people killed by guns every year in the United States is rising, and is projected to reach 32,929 in 2015, Dr Pandit said.

In the wake of notorious incidents of gun violence, many state legislatures have enacted or considered gun control. Dr Pandit and his team wanted to know whether such laws have resulted in fewer guns injuries.

From the Nationwide Inpatient Sample database, the researchers identified 2583 gun-related hospitalizations for trauma from 44 states in 2011.

They used the 100-point scoring system of the Brady Campaign to Prevent Gun Violence to measure the extent of gun control legislation in these 44 states. The system awards points for controls on gun purchase, background checks, assault weapons, child safety, and guns in public places.

California, with a score of 81, had the strictest gun control legislation, whereas Alaska, Arizona, and Utah, all with scores of 0, had the least strict legislation.

The researchers counted the number of injuries and deaths related to guns per 1000 trauma admissions. In states with more extensive gun regulations, there were fewer gun-related injuries, and the correlation was significant (R² = 0.75; P = .046).

The incidence of firearm-related injuries was a significant 30% lower in the 10 states with the strictest gun regulations (a score of 12 or more) than in the 34 states with the laxest laws (a score of less than 12) (P = .041).

Table. Gun Injuries in 44 States

Outcomes With Gun Control (n = 10) Without Gun Control (n = 34) P Value Gun injuries per 1000 trauma admissions, n 1.2 2.1 .37 Mortality rate, % 8.1 12.2 .03 Length of hospital stay for injured patients, days 4.2 3.9 .28

The overall cost to manage firearm-related injuries in these states was more than $200 million. Using the median age of a state resident and a lifespan of 75 years, the researchers calculated that these injuries resulted in 1129 potential life-years lost.

Dr Pandit acknowledged some weaknesses in the study. "Enforcement of these laws is the biggest limitation in all such studies, and is very difficult to control for," he explained. "Additionally, there might be a potential bias in the scoring system, but this is the best scoring system that we could use for our study."

Still, "it is important to improve and standardize gun legislation across the country," he said.

Study discussant Alberto Raul Ferreres, MD, from the University of Buenos Aires in Argentina, said, "It is a very nice study altogether, with a very thorough and very intelligent statistical analysis."

"This is a clear example of an application of the principle of justice and fairness. We can do something to have a benefit to the whole of society," Dr Ferreres said. "That benefit to the whole of society is fewer injuries, less disability, fewer dead people, and, of course, at the end of the day, lower hospital costs."

The National Rifle Association did not respond to a request for comment from Medscape Medical News.

Dr Pandit and Dr Ferreres have disclosed no relevant financial relationships.

American College of Surgeons (ACS) 2014 Clinical Congress. Presented October 29, 2014.