The connection was made by Vanderbilt University psychologist David Schlundt and his colleagues at Meharry Medical College in Nashville, Tenn.

“We found that when weight goes up, seatbelt use goes down,” Schlundt, associate professor of psychology and assistant professor of medicine, said. “This is an additional public health problem associated with obesity that was not on the radar screen. We hope these new findings will help promote awareness campaigns to encourage people to use their seatbelts and that additional resources, like seatbelt extenders, will be made more readily available.”

Schlundt and his colleagues examined 2002 data from the U.S. Centers for Disease Control’s Behavioral Risk Factor Surveillance Survey, a telephone survey used to collect data on risky behaviors and health decisions associated with death.

The study found that approximately 30 percent of individuals with a body mass index (kilograms per meter squared) that qualified them as overweight, obese or extremely obese reported not using a seatbelt, compared to approximately 20 percent of the average population. Furthermore, seatbelt use declined as BMI increased, with approximately 55 percent of extremely obese individuals reporting they did not use a seatbelt. The connection between increased body mass index and decreased seatbelt use held even when controlling for other factors, such as gender, race and seatbelt laws in the respondent’s state.

The scope of the public health problem posed by the lack of seatbelt use is magnified by the growing rate of obesity; nearly 60 percent of the survey respondents fell into the categories of overweight, obese or extremely obese.

“We know obesity increases the risk of cardiovascular disease, diabetes and some cancers,” Schlundt said. “We now know that increased risk of injury or death due to a car accident can be added to the list of risk associated with obesity.”

The authors suggest that a reason why people with a high BMI do not use seatbelts is because doing so is uncomfortable.

“Efforts should be made to raise public awareness about seatbelt extender availability, and manufacturers not offering seatbelt extenders should be encouraged, or required, to make them available,” they wrote. “Engineering solutions such as seatbelts with wider, more cushioned bands and greater adjustability may also be helpful by making seatbelts more comfortable for overweight and obese persons.”

Seatbelt usage reduces automobile crash-related deaths and injuries by at least 50 percent.

Source: Vanderbilt University