Obesity Can Be Fatal in Auto Accidents

Car crashes are more likely to be fatal for obese drivers, according to a national registry study, suggesting another good reason to add weight loss to resolutions for the new year.

A body mass index in the class II obesity range of 35 to less than 40 kg/m2 boosted risk of fatality in a severe crash by 21.2% compared with normal weight (P<0.0001), Seth Gemme, a medical student at SUNY at Buffalo, and colleagues found.

“The increased mortality among moderately to morbidly obese drivers is probably due to closer proximity to the steering column and comorbidities,” they speculated in the paper.

Obese drivers may be able to reduce their risk by choosing larger vehicles and moving their seat back sufficiently so that no part of their body touches the steering wheel, which can lessen the force of impact in an accident, Gemme suggested in an interview.

“Often morbidly obese people are stuck, though, because the seats don’t go back far enough,” he told MedPage Today. “They’re limited by what the manufacturer produces.”

Obesity significantly increased the likelihood of death to the driver for both men and women, although the risk was slightly higher for men.

But overweight — a BMI of 25 to less than 30 kg/m2 — actually appeared somewhat protective, with an odds ratio of 0.952 compared with normal weight (P=0.0293), and the “slightly obese” with a BMI of 30 to less than 35 kg/m2 weren’t at elevated risk (OR 0.996, P=0.7758).

The researchers cautioned that waist circumference may have been a more accurate determinant of obesity, since large muscle mass can throw off BMI, but wasn’t reported in the database.

Also, the study couldn’t account for safety features of the vehicles involved in the crashes studied, they noted.

If more obese individuals are already buying bigger, safer cars, “then it is possible that our results underestimate the increased mortality risk of the severely obese,” Gemme’s group warned in the paper.

Their elevated mortality in car crashes may be a contributor to the overall population risk, but comorbidities could be a confounding factor as diabetes, cardiac disease, and other conditions may boost risk of dying from injuries sustained in an accident, the researchers noted. Read more at www.medpagetoday.com

Fat Canaries in a Coal Mine

If it were just kids, we could blame obesity on the cutbacks in phys-ed classes, school vending machines that sell high-calorie junk, and the substitution of videogames for kickball. If it were just adults, we could blame obesity on supersizing, fast-food meals, and pedestrian-unfriendly towns that force everyone into a car. But while 68 percent of American adults qualify as overweight or obese, and 17 percent of children do (compared with 5 percent in 1971), there are other increasingly pudgy populations. Meet some overweight pets, lab animals, and even urban rats.

David Allison, an obesity researcher at the University of Alabama at Birmingham, has long criticized the Big Two explanation for America’s thundering thighs: dwindling physical activity as a result of social changes like fewer sidewalks, and increasing calorie intake as a result of nefarious food-industry marketing. By chance, he came upon a record of marmosets in a Wisconsin research colony: the little primates’ weight had soared over the previous 15 or so years, even though they had not been bred for larger size, switched chow supplier, or undergone any other change that would obviously explain their extra heft. That set Allison looking for weight records of other animals.

With colleagues, he scrutinized the weight histories of 24 populations, from alley rats in Baltimore to lab macaques in California and even control groups of mice in federal toxicology studies. In a paper to be published in Proceedings of the Royal Society B (for biology), they report that in 23 of the 24—eight species, 20,000-plus animals—the percentage of obese individuals has risen since the 1940s (or since the oldest records they found). The odds of that happening by chance are 8 million to 1. And since neither feral rats nor lab chimps nor any of the others have cut back on phys ed or patronized vending machines more, says Allison, we need to look for explanations beyond the Big Two. Read more at www.newsweek.com