What Can You Believe? Epidemiology and the Headlines
Network - Summer 2008
No matter how you get the news — from television, radio, newspapers, magazines or the Internet — you’re bound to hear about studies on how lifestyle behaviors may affect your risk of disease. While some of these findings may seem far-fetched, others may sound reasonable, and still others may be contradictory. What’s a reader to believe?
For example, is coffee good or bad for your health?
In 1981, researchers announced that more than one cup of coffee a day may triple your risk of pancreatic cancer. Then, in 2001, other researchers carrying out a larger investigation refuted those findings. Likewise, in 1998, scientists said coffee reduces the risk of colorectal cancer. Another group reported in 2005 that this wasn’t true.
These were observational studies carried out by epidemiologists, researchers in the branch of medicine that investigates the causes and patterns of disease. Basically, their role is not to change certain behaviors but to collect data about them and, then, draw conclusions.
But how can you know if their conclusions are pertinent to you?
How to be discerning
“People need to learn how to read the news,” says Sara Strom, Ph.D., associate professor in the Department of Epidemiology. “An important question you should ask yourself when you read about one of these studies is ‘Does this apply to me?’”
Other questions she suggests include:
- Do you have the same characteristics as the study participants: the same gender, race, age bracket, economic status and lifestyle?
- Are the results too good to be true?
- Do they apply to your disease or health status?
- Are they only comparing extreme groups to which you do not belong?
- Did a reliable group carry out the study?
- Did a reliable source fund the study?
- If the study can be applied to you, are you willing to make the lifestyle changes it might entail?
“I tell people: Don’t waste time on what doesn’t apply to you,” Strom says. “Watch out for information on the Internet and pay attention to the science.”
Types of epidemiologic studies
Epidemiologic studies can take several forms.
A cohort study follows a healthy group of people over time and looks at who gets disease. If it’s a coffee study, they may look at the effects of coffee in groups of people.
A case-control or retrospective study examines people with and without a certain disease, for example, like the colon cancer study above. Then, it will compare the habits of those who have disease with those who don’t.
An advantage of an epidemiologic study over an experimental one is that it is based on a large number of participants.
Epidemiologic studies at M. D. Anderson go deeper
At M. D. Anderson researchers dig deeper. In their efforts to discover and understand how environment, diet, exercise and other lifestyle elements play a role in the risk of developing cancer, they also look at molecular, genetic and nutritional epidemiology.
There are many multi-disciplinary, national and international studies currently funded. In these studies, researchers are collecting and studying data that may be disease-specific, may look at familial, ethnic and cultural aspects or may involve underserved populations.
Most recently, Strom has been involved in studies that are the first to examine the relationship between obesity and prostate cancer progression after primary therapy with external beam radiation therapy, a common treatment option.
Findings in parallel studies carried out by Strom and her colleagues showed:
- That a history of weight gain or obesity at the time of diagnosis played a role in how aggressive prostate cancer may become after surgery.
- That obese prostate cancer patients should be followed more closely after radiation treatment.
Sara Strom, Ph.D. (right), along with her colleague Hui Zhang, M.D., examines the relationship between diet and prostate cancer.
“The fact that the same association was found among patients with different risk profiles, and who were treated with different therapies, would suggest that poorer outcomes in obese men are not related to differences in treatment as much as to differences in tumor behavior between obese and non-obese men,” Strom says.
These are only two examples of the depth of epidemiologic research being done at M. D. Anderson and published in reputable journals. The quality of the studies has led to increased funding and publication in the top national and international journals.
M. D. Anderson is striving to communicate information on new discoveries in a way that the public can understand and believe.
However, stories of interesting epidemiologic findings will continue to fill the airwaves, publications and Internet sites, as the news media brings “breaking news” to the public.
To that end, Strom recommends, “Reflect on what motivates people to write about certain studies and remember: There are no magic bullets. Use common sense and consult a health care professional about results that you think might apply to you.”