Federal Practitioner: In what ways do you think obesity has an effect on cancer recovery?
Wendy Demark-Wahnefried, PhD, RD: There are several studies that directly link obesity with cancer outcomes, such as survival. At present, most of those studies are observational. But we do know that there is a strong association between obesity and the risk of 9 different cancers and on patients’ chances of survival after they’ve been diagnosed. And for many of those cancers, obesity is a poor prognostic factor.
We also know that obesity does affect some of the aspects that relate to recovery. For example, people who are overweight or obese compared with people who are normal weight have poor wound healing and a higher rate of lymphedema after their surgery; particularly women with breast cancer, who have roughly a 2 to 3 times higher risk than women who are of normal weight.
Overweight individuals also spend more time in the recovery room, because they often are given higher amounts anesthesia to get through their operation. They also have a reduced quality of life, and most of that relates to their ability to perform various aspects of physical functioning, whether it be walking, getting up from a chair, or carrying groceries. So they have a harder time getting back into the mainstream of life.
And last but not least, they have higher rates of comorbidity. The patient who has cancer is more at risk for developing heart disease and diabetes, and obesity can really complicate that.
FP: Do you think we are just skimming the surface of what we know about the connection between obesity and cancer recovery? Is there more research that needs to be done?
WD-W: Most definitely. Like I pointed out as we started this conversation, a lot of our data are observational. Do we know what’s the chicken and what’s the egg here? Is it because people are obese that they are experiencing more of these adverse effects or vice versa? So really, as we develop more and more studies that look at weight loss or that test weight loss in cancer survivors, we’ll be able to get some answers in this area and some hard data.