This report originally appeared in the September 2011 issue of DOTmed Business News

While the health consequences of obesity, such as heart disease and diabetes, have been well publicized, the challenge of providing health care to this ever-growing population is recently grabbing more media attention.

More than one-third of adults (over 72 million people) are obese in the United States today and these rates have doubled since 1980, according to the Centers for Disease Control and Prevention. And experts say the current obesity epidemic is on track to progress each year. A study in the October 2008 issue of Obesity, in fact, projected if the current trends in the obesity rates continue, 86 percent of adults will be overweight or obese and 51 percent will be obese by 2030.

“What happens is that when you shift the weight curve where the average person is heavier, you get a much bigger increase in the percentage of people who are severely obese,” says Dr. Larry Cheskin, director and founder of the Johns Hopkins Weight Management Center in Baltimore. “We’re hardly finding anyone who is underweight these days unless they have some sort of undiagnosed health condition.”

The obesity epidemic also impacts the nation’s wallet. In 2008, overall medical care costs related to obesity for adults were estimated to be as high as $147 billion, says the CDC.

So who exactly is considered obese? A body mass index of 30 or above pushes a person into the obese category. And anyone 100 pounds above their ideal body weight, with a BMI higher than 40, is thought of as “morbidly obese.”

When patients tip the scales at such heavy numbers, providing routine medical care becomes increasingly difficult. Everything from a simple weigh-in to obtaining an accurate medical image or performing surgery requires diversions from normal treatment procedures. Examination tables and hospital scales, for example, often have a maximum capacity to only support a patient who weighs up to 350 pounds.

“If you have a really large patient and you must get their weight, unfortunately, you often have to use a laundry scale or send them to a veterinary school or zoo to be weighed,” says Dr. Chemen Tate, associate professor of obstetrics and gynecology at Indiana University Hospital in Indianapolis. “If your patient is in the 400 to 500 pound range, there just aren’t scales in the hospital to measure someone that heavy.”

Tate explains that obesity can also increase a patient’s risk of complications during surgical procedures.

“Performing surgery on obese patients can be disastrous,” she says. “Technically, it can be very difficult because it takes surgeons longer to get to the particular organ we’re interested in and there can be increased blood loss and increased operative time.”

Telling obese patients that their weight requires a physician to treat them differently than they would a normal-weight patient is always a difficult conversation to have, says Cheskin.

“When physicians have to tell patients, ‘you are so heavy that we can’t do our usual tests,’ it’s discouraging for the patients to hear,” says Cheskin. “Even though we state it factually and scientifically, patients feel badly and we’re the ones delivering the news.”

Dr. James Brink, chair of the American College of Radiology’s Body Imaging Commission, says radiologists also face a dilemma when medical images—CT scans, MRI, or ultrasounds—are requested for severely obese patients.

Ultrasound, he explains, is probably the modality most degraded by obesity, especially as the patient nears 250 pounds. The ultrasound is not able to penetrate excessive fat well and typically yields poor image quality.
“Some of the challenges we face with obesity are based on simple laws of physics and there’s not a lot we can do about it,” says Brink.

In days gone by, the morbidly obese have also been excluded from having CT scans or MRI, says Brink, either because they exceeded the table’s weight capacity or were too wide to fit into the machine. Traditional MR scanners that can feel too confining for even a normal-weight person have a diameter of 60 centimeters (23.6 inches) and a table capacity of 350 pounds.

In an ACR report, “Radiology’s Big Challenge: Imaging the Morbidly Obese,” researchers from Harvard Medical School detailed cases from radiologists where even if obese patients “were able to squeeze through the CT gantries or MR bores, the resulting images were often subpar, sometimes strikingly so.”
Brink says, however, that recent design changes to imaging machines are offering a promising outlook for the future.

“It’s only through conversations between radiologists and manufacturers that I’m happy to report that manufacturers have produced larger machines that are now amenable to the obese,” he says.

Manufacturers have developed newer MR scanners with a diameter or bore of 70 centimeters (27.5 inches) and a weight capacity of 550 pounds, according to the team from Harvard. Newer CT scanners also have gantry diameters of up to 90 centimeters (35 inches) and table capacities up to 680 pounds. In their report, however, Dr. Raul Uppot, and fellow researchers found that in both newer and older models, up to 7 inches of a CT unit’s gantry diameter is taken up by the table itself, which results in a smaller capacity than advertised.

In their discussion of the innovations made with CT scanners, the researchers concluded that if a morbidly obese patient can fit into a scanner, the “image quality is diagnostically acceptable with details of small structures visible even in the most obese patients.”

GE Healthcare and Philips Healthcare are two of the manufacturers offering this new generation of what’s being called “wide bore scanners.” GE introduced its first wide bore MR system, the Optima MR450w, as one that delivers “both uncompromised image quality and patient comfort,” according to the company’s website. GE says the system “increases accessibility for claustrophobic and obese patients—without sacrificing high-resolution imaging, patient comfort, or clinical productivity.”

But have these large scanners been acquired in many hospitals across the country?

“Certainly the larger hospitals are more likely to have the latest technology than smaller facilities,” says Brink. “The more CT scanners a hospital has, the more likely it is to replace the equipment more regularly and purchase the newer, larger models.”

Although the newer models can be costly, they can accommodate patients of all sizes, according to the Harvard report.

Brink goes on to explain that another challenge facing radiography and the morbidly obese patient is that these patients are subjected to increased exposure to harmful doses of radiation during the diagnostic procedures.
“Heavy patients need more X-ray to penetrate their body, either with CT scan or fluoroscopy, and the radiation dose goes up and becomes unevenly distributed through the body,” he says.

The ACR has made it a goal to increase efforts to find ways that will allow radiologists to obtain images without exposing patients to these harmful doses. Brink says there is a lot of research now being conducted that includes, for example, hardware that uses fewer photons to capture images.