Originally Published: 01 DEC 22 06:36 ET

Updated: 01 DEC 22 12:46 ET

By Raenu Charles, CNN

(CNN) -- Organ donations and transplantations increase during major US motorcycle rallies due to crashes, according to a new study, signaling a need for increased safety measures.

The researchers analyzed more than 10,000 organ donations and 35,000 transplantations from 2005 to 2021. In regions near where motorcycle rallies were held, there were 21% more organ donors and 26% more transplant recipients per day during rallies than in the four weeks before and after.

In nearby areas without a motorcycle rally on those same dates, there were 11% fewer organ donors and 10% fewer transplant recipients.

"Clearly, there are preventable deaths happening during these events, and the focus first and foremost should be improving public safety and traffic safety during these events," said Dr. David Cron, first author of the study and a clinical fellow at Massachusetts General Hospital.

Such large events can also "have downstream associations with organ donation and transplant," the study says.

The research, published in the journal JAMA Internal Medicine, tracked organ donations and transplantations around seven of the largest motorcycle rallies across the United States: the Sturgis Motorcycle Rally in South Dakota, Daytona Bike Week in Florida, Laconia Motorcycle Week in New Hampshire, Myrtle Beach Bike Week and Atlantic Beach Bikefest in South Carolina, the Republic of Texas Biker Rally and Bikes, Blues & BBQ in Arkansas. Each of these events draws 200,000 to 500,000 attendees every year.

Large motorcycle rallies often come with a surge in trauma volume at local hospitals, the study says. Overall, bikers are 29 times more likely to die in a crash per mile traveled compared with people in passenger vehicles, the researchers note, and bikers who aren't wearing helmets are three times more likely than helmeted bikers to become organ donors.

Isolated head injuries are one of the leading causes of brain death, which is among the most common catalysts of organ donation, Cron said.

"This topic has been talked about in the context of motorcycles and helmets ... because over the past few decades, helmet laws have been scaled back, and what's been well-documented is that there are more fatal crashes from whenever riders aren't wearing their helmets," he said.

Bringing awareness to organ donation was an important aspect for the researchers.

"Education and outreach really goes a long way towards educating the public about organ donation, whether it's registering to make your wishes known -- such that if something tragic were to happen, that you had potential to be a deceased organ donor -- or even just improving public's knowledge of living donation," Cron said.

For everyone involved in the transplant process, including critical care teams and organ procurement organizations, "it's important to recognize these events as times of increased availability of organ donors so that they can all be ready for these events and optimize their processes in any way that may be to maximize the ability to turn these projects into, hopefully, a gift to life," he said.

Only 1% of people who die in the United States every year are medically eligible to become organ donors, the Association of Organ Procurement Organizations said Tuesday in a statement.

"We appreciate the researcher's bringing attention to this issue and to the need for greater public safety and organ donation awareness among communities that host and attend motorcycle rally events," the group said.

Safer riding

The Sturgis Motorcycle Rally, held each August, is the largest and most popular in the country.

"Unlike travelers who choose a destination and remain in that destination location for an entire week, Rally attendees come here to experience the freedom of the rides through some of the most picturesque scenery in the country. In doing so, they log more time on our highways that put them at higher risk of an accident," said Daniel Ainslie, manager for the city of Sturgis, which helps organize the rally.

The South Dakota Office of Highway Safety offers tips for safer riding, such as reviewing riding maps before attending, knowing how to handle a bike in varying weather and terrain conditions, and practicing safe driving, such as checking blind spots and using appropriate signaling.

According to the study, 42% of all motorcycle crashes in 2019 involved alcohol. To cut down on the risk of drinking and driving during the rally, Sturgis offers bus rides from local motels and rally campgrounds.

"Having the buses gives Rally attendees the option to spend time in downtown Sturgis without worrying about putting themselves or their passengers in danger when returning to where they are staying," Ainslie said.