April 8, 2005
Pulmonology
Anatomy of an Asthma Attack
Complexity
Precursor Cells Follow Different Paths to Same
Cell Fate
Genetics
Gene Network Predicts Stroke Risk in Sickle Cell Anemia
Education
Harvard Approves MD–PhD Program in Social Sciences
No Link Seen Between Dietary Patterns and Pancreatic Cancer Risk
New Heart Attack Therapy May Be Coming
Proceedings of the HMS
Faculty Council
New Appointments to Full Professor
Stem Cell Research at BID Gains $6 Million Gift
Honors and Advances
News Brief: Soros New American Fellowship
In Memoriam
Survey Seeks to Improve
Student Life on Longwood
No Link Seen Between Dietary Patterns and Pancreatic Cancer Risk
A team of researchers led by Dominique Michaud, HSPH assistant professor of epidemiology, and Charles Fuchs, HMS associate professor of medicine at the Dana–Farber Cancer Institute, has found that broad dietary patterns do not change a person’s risk of pancreatic cancer. The study, published in the Journal of the National Cancer Institute on April 6, is based on periodic questionnaires and health reporting from almost 125,000 medical professionals, 366 of whom developed the disease over 16 years of follow-up.
Previous studies were divided on the role of diet in pancreatic cancer, which has the fourth highest mortality among cancers in the United States. Michaud said the disease is hard to study, in part, because patients get ill so quickly. “Pancreatic cancer is so fatal that in the past most studies have had to rely heavily on proxy interviews, where family members answer a questionnaire for a patient, which can be very inaccurate. I think prospective studies will have an important role in understanding dietary factors related to this disease,” Michaud explained.
| The scientists could find no match between the Western diet and an increased risk of pancreatic cancer. |
The detailed information on eating habits allowed the researchers to correlate diets into two patterns. The Western dietary pattern is high in refined grains, meat, and fat, while the so-called “prudent” diet is high in vegetables, fruits, and whole grains. This approach had paid off for HSPH researchers in the past: type 2 diabetes and colorectal cancer were previously found to be associated with Western dietary tendencies.
But Michaud and her colleagues could find no match between the Western diet and an increased risk of pancreatic cancer. They tried stratifying the results by body mass index and by smoking status to see if being overweight or using nicotine might be enabling a dietary effect, but dietary patterns did not seem to be a factor in these subgroups either. Michaud still believes diet is a key to the disease because high glycemic load and obesity raise the risk of pancreatic cancer, but the Western-vs.-prudent diet model is not helpful in this case.
Michaud says the next steps will be to look into mechanistic questions about the causes of pancreatic cancer; Fuchs is lining up serological markers for that effort. Another ongoing research area examines individual nutrients from reported diets to see whether too much or not enough of something is linked to the deadly malignancy.
New Heart Attack Therapy May Be Coming
Platelets often continue to stick together in the aftermath of a heart attack, causing arteries that were opened to close back down and triggering a second heart attack, a stroke, or even death. To improve recovery, clot-busting cocktails may soon include a new component, the antiplatelet agent clopidogrel, which was evaluated in a study in the March 24 New England Journal of Medicine. Lead author Marc Sabatine, an HMS instructor in medicine and a cardiologist at Brigham and Women’s Hospital, said the drug was the first pharmacological advance in treating serious heart attacks in more than a decade.
| A decision to include clopidogrel in clot-busting cocktails in the United States is expected soon. |
The TIMI–CLARITY team, led by HMS associate professor Christopher Cannon, looked at how well the drug cocktail opened the blocked artery. More than 90 percent of the patients underwent angiography, and a dedicated, blinded laboratory evaluated blood flow to the heart. The primary endpoints of the study were a blocked coronary artery or death or a second heart attack prior to angiography. Clopidogrel was credited with a 36 percent reduction in the odds of these outcomes. The drug also was found to be equally beneficial regardless of which additional drugs were in the clot-busting cocktail, the patient’s age, sex, or the location of the heart attack. Bleeding, especially intracranial hemorrhage, is always a risk to be weighed against the benefits of clot-busting drugs, but the TIMI study group found that clopidogrel did not add to the risk of this complication.
Based on this study and a larger trial in China focused on reducing mortality, a decision to include clopidogrel in clot-busting cocktails in the United States is expected soon. Sabatine believes the drug may find use around the world because it is inexpensive, safe, and effective. “For $3 per pill,” he said, “you get this benefit which is not too different from other interventions costing thousands of dollars.”