Graham Colditz

When the Institute of Medicine (IOM) of the National Academy of Sciences sought expertise in this area for a larger report on the future of cancer prevention, it turned to HCCP. The IOM’s National Cancer Policy Board, which oversaw the study, contracted with Graham Colditz, professor in the Department of Epidemiology and director of education at HCCP. The request was to summarize the current epidemiological evidence linking five lifestyle risk factors to cancer incidence: tobacco use, physical inactivity, overweight and obesity, poor diet, and alcohol use.

On March 10, the IOM published "Fulfilling the Potential of Cancer Prevention and Early Detection," available online at http://www.iom.edu under "Recent Reports." The report calls for stepped-up efforts, coordinated by the US Department of Health and Human Services, to modify across the American population lifestyle factors that strongly influence not only the risk of cancer but also of other major health problems, including heart disease, diabetes, and osteoporosis. The epidemic of obesity, unhealthy diet, and physical inactivity is a special concern, with the report noting that obese individuals have a 33 percent increased risk of cancer.

Communicating information on reducing cancer risks to the public is essential if people are to make significant changes in health behaviors, says the report. This is an area in which HCCP has extensive experience, including creating the popular ‘Your Cancer Risk’ web site. But the report also acknowledges the many barriers to achieving population-wide changes in health behaviors. Among the report’s recommendations is that Congress fund the Centers for Disease Control and Prevention to help states develop community-based interventions.

Both HCCP and the IOM report authors recognize the need "to act on what we know rather than merely doing more research on the effectiveness of prevention strategies," said Colditz, who works with HCCP head and HSPH professor David Hunter to get cancer research results to the public. The report calls for "setting a blueprint to move prevention higher up on the agenda" in the health services system across the country, Colditz added.

In practice, the report’s authors say, health care providers can do more to boost quit rates among their smoking patients; health plans can improve the use of early detection tests by covering their costs and having systems in place to remind physicians and patients about them; communities can enact policies to curb exposure to secondhand smoke, limit access to tobacco products by teenagers, and create safe places for physical activity.

"One thing that's new here is the strong emphasis on obesity and dietary factors," said Nancy Mueller, professor in the Department of Epidemiology, who served on a sub-committee of the National Cancer Policy Board that monitored the report. HCCP was chosen to contribute to the report because Colditz and his colleagues are among a small number of scientists who could carry out this kind of analysis, said Mueller. "We've moved beyond thinking in terms of individual nutrients to the balance of what you eat and the energy you expend and the importance of a healthy diet rich in fruits and vegetables."

In the past, many projections of the magnitude of cancer risk reduction through behavior change have proven overly optimistic. The National Cancer Institute set a goal of reducing cancer deaths by 50 percent between 1980 and 2000, only to see mortality rates increase through the 1980s, peaking between 1990 and 1992. Since then, however, the mortality rate has declined slightly, down 7 percent from 1980 to 1997.

Colditz, who said that in theory about half of cancer is preventable, cites a more conservative projection–cancer incidence could be reduced by 13 percent and mortality by 21 percent compared to 1990 baseline rates by 2015.

HCCP members Hank Dart, Catherine Tomeo Ryan, Laurie Fisher, Geetanjali Datta, and Beverly Rockhill served as consultants to the IOM report. Rockhill is no longer with HCCP.

--Richard Saltus