JAMA news releases are made available to the public after 3 pm US Central time on the first 4 Tuesdays of each month. The Archives Journals news releases are made available to the public after 3 pm Central time on Mondays. We also provide a list of previous news releases.
THIS WEEK'S CONTENT
JAMA NEWS RELEASES
(Embargoed for Release: 3:00 p.m. CT, Tuesday, January 16, 2007)
JAMA NEWS RELEASES
CHEMOTHERAPY APPEARS TO DELAY CANCER RECURRENCE FOLLOWING SURGERY FOR PANCREATIC CANCER
SOUTH ASIANS HAVE HIGHER LEVELS OF HEART ATTACK RISK FACTORS AT YOUNGER AGES
STATISTICAL METHOD USED INFLUENCES RESULTS OF OBSERVATIONAL STUDIES
JAMA REPORT (VIDEO SCRIPT)
VIDEO: Windows Media | Quicktime
STUDY IDENTIFIES WHY PEOPLE FROM SOUTH ASIAN COUNTRIES SUFFER HEART ATTACKS YEARS EARLIER THAN OTHER ETHNICITIES
INFORMATION CONTAINED IN THESE NEWS RELEASES IS PROTECTED BY COPYRIGHT. JOURNAL ATTRIBUTION IS REQUIRED.
This week's JAMA Report video is on the risk factors for South Asians of a heart attack at a younger age. The report will be fed Tuesday, January 16, from 9:00 - 9:30 a.m. ET and 2:00 - 2:30 p.m. ET, on Intelsat America 6 (C-Band), Transponder 09, Downlink Frequency 3880 MHz Vertical, Audio: 6.2/6.8. For more information, call 312/464-JAMA.
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Embargoed for Release: 3:00 p.m. CT, Tuesday, January 16, 2007
Media Advisory: To contact Helmut Oettle, M.D., Ph.D., email: helmut.oettle{at}charite.de. To contact editorial author Al B. Benson III, M.D., call Marla Paul at 312-503-8928.
CHEMOTHERAPY APPEARS TO DELAY CANCER RECURRENCE FOLLOWING SURGERY FOR PANCREATIC CANCER
CHICAGO—Use of the drug gemcitabine for chemotherapy significantly delays the recurrence of cancer, compared to no chemotherapy, for patients following pancreatic cancer surgery, according to a study in the January 17 issue of JAMA.
With an estimated 232,000 new cases per year, pancreatic cancer is among the most common malignancies worldwide. It is also one of the most lethal cancers, with a mortality incidence ratio of 98 percent, according to background information in the article. Pancreatic cancer is the fourth leading cause of death from cancer in the U.S., with 32,300 deaths estimated in 2006. Surgery is the only curative treatment option for this type of cancer, though the prognosis still often remains poor. Therefore, surgery alone is an inadequate approach to achieve long-term disease control in patients with resectable (surgically remove a part of an organ) pancreatic cancer.
Helmut Oettle, M.D., Ph.D., of Charite School of Medicine, Campus Virchow-Klinikum, Berlin, Germany, and colleagues conducted a study (CONKO-001) comparing use of the drug gemcitabine with no anticancer drug therapy in 368 patients who had undergone complete resection of pancreatic cancer. The study was conducted from July 1988 to December 2004 at 88 oncology centers in Germany and Austria. Patients received chemotherapy with gemcitabine (n = 179), or no chemotherapy (observation; [control, n = 175]).
With a median (midpoint) follow-up of about 4.5 years, recurrent cancer developed in 74.3 percent in the gemcitabine group and 92 percent in the control group. The estimated median disease-free survival was 13.4 months in the gemcitabine group compared with 6.9 months in the control group. Estimated disease-free survival at 3 and 5 years was 23.5 percent and 16.5 percent in the gemcitabine group, and 7.5 percent and 5.5 percent in the control group, respectively. There was no difference in overall survival between the gemcitabine group and the control group.
“The results of CONKO-001 indicates that adjuvant treatment with gemcitabine in the dose and schedule used has minimal toxicity, does not compromise quality of life, and offers a good, and currently perhaps the best, chance for prolonged disease-free survival in patients undergoing [certain types of] resection for pancreatic cancer,” the authors conclude.
(JAMA. 2007;297:267-277. Available pre-embargo to the media at www.jamamedia.org)
Editor's Note: This trial was supported in part by a grant from Lilly Deutschland, Bad Homburg, Germany. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
EDITORIAL: ADJUVANT THERAPY FOR PANCREATIC CANCER - ONE SMALL STEP FORWARD
In an accompanying editorial, Al B. Benson III, M.D., of the Feinberg School of Medicine, Northwestern University, Chicago, comments on the study by Oettle and colleagues.
“Worldwide, there is a need to move away from the question of current chemotherapy agents vs. chemoradiation to a research focus based on enhancing understanding of biologic principles. Given the rapid lethality of pancreatic cancer, this is no easy task. Whether it is possible to build on the small steps taken with CONKO-001 results remains to be seen. It is unlikely, however, that these small steps alone will provide the necessary enhancement of benefit beyond the improvements in surgery to profoundly alter the course of this most challenging of cancers.”
(JAMA. 2007;297:311-313. Available pre-embargo to the media at www.jamamedia.org)
Editor's Note: Dr. Benson reported that he has been a consultant to Eli Lilly, but the research funding goes directly to his institution and not to him personally.
For More Information: Contact the JAMA/Archives Media Relations Department at 312/464-JAMA (5262) or email: mediarelations{at}jama-archives.org.
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Embargoed for Release: 3:00 p.m. CT, Tuesday, January 16, 2007
Media Advisory: To contact corresponding author Salim Yusuf, M.D., D.Phil., call Veronica McGuire at 905-525-9140, ext. 22169.
SOUTH ASIANS HAVE HIGHER LEVELS OF HEART ATTACK RISK FACTORS AT YOUNGER AGES
CHICAGO—People who are native to South Asia experience heart attacks at a younger age because of greater levels of heart attack risk factors such as smoking and diabetes at a younger age, according to a study in the January 17 issue of JAMA.
The South Asian countries of India, Pakistan, Bangladesh, Sri Lanka, and Nepal account for about a quarter of the world’s population and contribute the highest proportion of cardiovascular diseases compared with any other region globally. Deaths related to cardiovascular disease occur 5 to 10 years earlier in South Asian countries than in Western countries, according to background information in the article. This has raised the possibility that South Asians exhibit a special susceptibility for acute myocardial infarction (AMI; heart attack) that is not explained by traditional risk factors. Despite documenting the higher rates of earlier coronary heart disease (CHD) in South Asians, few studies have been able to shed light on its reasons.
Prashant Joshi, M.D., of the Government Medical College, Nagpur, India, and colleagues attempted to determine the reasons for the higher rates of CHD in native South Asians compared with individuals from other parts of the world. The study included 1,732 heart attack patients and 2,204 controls from 15 medical centers in 5 South Asian countries and 10,728 heart attack cases and 12,431 controls from other countries.
The researchers found that the average age for first heart attack was lower in South Asian countries (53.0 years) than in other countries (58.8 years). The prevalence of protective risk factors (leisure time physical activity, regular alcohol intake, and daily intake of fruits and vegetables) were markedly lower in South Asian study participants compared with those from other countries.
Some harmful factors were more common in native South Asians than in individuals from other countries: history of diabetes, current and former smoking, history of hypertension, psychosocial factors such as depression and stress at work or home, and elevated ApoB/ApoA-I ratio (a protein/lipid). When stratified by age, South Asians had more risk factors at ages younger than 60 years.
“The younger age of first AMI among the South Asian cases in our study appears to be largely explained by the higher prevalence of risk factors in native South Asians,” the authors write. “These data suggest that lifestyle changes implemented early in life have the potential to substantially reduce the risk of AMI in South Asians.”
(JAMA. 2007;297:286-294. Available pre-embargo to the media at www.jamamedia.org)
Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
For More Information: Contact the JAMA/Archives Media Relations Department at 312/464-JAMA (5262) or email: mediarelations{at}jama-archives.org.
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Embargoed for Release: 3:00 p.m. CT, Tuesday, January 16, 2007
Media Advisory: To contact Therese A. Stukel, Ph.D., call Julie Dowdie at 416-480-4780. To contact editorial co-author Ralph B. D’Agostino, Sr., Ph.D., call Kira Edler at 617-358-1240.
STATISTICAL METHOD USED INFLUENCES RESULTS OF OBSERVATIONAL STUDIES
CHICAGO—A study comparing different statistical methods used to remove the effects of selection bias in observational studies finds that results may vary and caution may be warranted when interpreting findings of studies using certain methods, according to an article in the January 17 issue of JAMA.
With financial, practical, and ethical challenges involved in undertaking randomized clinical trials (RCTs), investigators often use observational data to compare the outcomes of different therapies, to guide policy statements and clinical protocols, and in generalizing results to the community. However, these comparisons may be biased due to important baseline differences in prognostic factors among patients, often as a result of unobserved treatment selection biases, according to background information in the article.
Therese A. Stukel, Ph.D., of the Institute for Clinical Evaluative Sciences, Toronto, and colleagues compared four analytic methods applied to the same data to determine if the estimated benefit from invasive therapy depends on the statistical method used to adjust for overt (measured) and hidden (unmeasured) bias. Methods included multivariable model risk adjustment, propensity score risk adjustment, and propensity-based matching, which control for overt bias, and instrumental variable analysis, which is a method designed to control for hidden bias as well.
The study included 122,124 patients who were elderly (age 65-84 years), receiving Medicare, and hospitalized with acute myocardial infarction (AMI; heart attack) in 1994-1995, and who were eligible for cardiac catheterization. Patients who received cardiac catheterization (n = 73,238) were younger and had lower AMI severity than those who did not. Baseline chart reviews were taken from the Cooperative Cardiovascular Project and linked to Medicare health administrative data to provide a set of prognostic variables. Patients were followed up for 7 years through December 2001, to assess the association between long-term survival and cardiac catheterization within 30 days of hospital admission.
The researchers found that, even after accounting for prognostic variables, cardiac catheterization was associated with an approximate 50 percent relative decrease in death rate, using standard risk-adjustment methods such as multivariable model risk adjustment, propensity score risk adjustment, or propensity-based matching. Using regional catheterization rate as an instrument, the instrumental variable analysis showed a 16 percent relative decrease in the death rate. The survival benefits of routine invasive care from randomized clinical trials are between 8 percent and 21 percent.
“Within a large observational data set, the estimated association of invasive cardiac treatment with long-term mortality is sensitive to the analytic method used,” the authors write.
“Randomized clinical trials cannot be undertaken in all situations in which evidence is needed to guide care. Well-designed observational studies are still needed to assess population effectiveness and to extend results to a general population setting. Our study serves as a cautionary note regarding their analysis and interpretation. First, propensity scores and propensity-based matching have the same limitations as multivariable risk adjustment model methods, and are no more likely to remove bias due to unmeasured confounding when strong selection bias exists. Second, instrumental variable analyses may remove both overt and hidden biases but are more suited to answer policy questions than to provide insight into a specific clinical question for a specific patient. Caution is advised regarding clinical protocols and policy statements for invasive care based on expected mortality benefits derived from traditional multivariable modeling and propensity score risk adjustment of observational studies,” the researchers conclude.
(JAMA. 2007;297:278-285. Available to the media at www.jamamedia.org)
Editor's Note: This study was supported by grants from the Robert Wood Johnson Foundation, the U.S. National Institute of Aging, and a Canadian Institutes of Health Research Team Grant in Cardiovascular Outcomes Research. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
EDITORIAL: ESTIMATING TREATMENT EFFECTS USING OBSERVATIONAL DATA
In an accompanying editorial, Ralph B. D’Agostino, Jr., Ph.D., of Wake Forest University School of Medicine, Winston Salem, N.C., and Ralph B. D’Agostino, Sr., Ph.D., of Boston University and Harvard Clinical Research Institute, Boston, discuss the findings of the analysis of observational studies.
“… the article by Stukel et al is an important reminder of the need for careful and rigorous approaches to observational data analyses. Because the final inferences appear different depending on the method chosen, investigators must be cautious when conducting observational data analyses and must ensure that they have available what they consider to be the most important patient characteristics measured before treatment assignment. Furthermore, the analytic method for comparing treatments must be shown to properly balance these characteristics. In addition, sensitivity analyses also should be performed in much the same way as Stukel et al did. Moreover, external validation of results should be attempted, but always with caution.
“RCTs should not always be considered as the only source of valid scientific information. The data collected from such studies are strong only if it can be shown that in fact a truly random sample of eligible patients participate and complete the protocol as designed. When patients self-select to be included in observational studies, the findings may more accurately reflect ‘real world’ experience, but if and only if optimal, rigorous, and appropriate methods for dealing with selection bias and confounding are part of the analytic plan,” they write.
(JAMA. 2007;297:314-316. Available pre-embargo to the media at www.jamamedia.org)
Editor's Note: Financial disclosures – none reported.
For More Information: Contact the JAMA/Archives Media Relations Department at 312/464-JAMA (5262) or email: mediarelations{at}jama-archives.org.
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JAMA REPORTS
VIDEO: Windows Media | Quicktime
STUDY IDENTIFIES WHY PEOPLE FROM SOUTH ASIAN COUNTRIES SUFFER HEART ATTACKS YEARS EARLIER THAN OTHER ETHNICITIES
VIDEO:
B-ROLL
Dr. Yusuf examining Jacob Joseph – sequence with stethoscope/listening to heart
AUDIO:
FIFTY-SEVEN YEAR OLD JACOB JOSEPH, WHO’S ORIGINALLY FROM INDIA, HAS HAD SERIOUS HEART PROBLEMS FOR FOUR YEARS. HE HAS INDIAN FRIENDS WHOSE HEART DISEASE STARTED EVEN EARLIER.
VIDEO:
SOT/FULL
@ :10
Super: Jacob Joseph
Heart patient
Runs :11
AUDIO:
“I have even heard this morning someone as young as 35 or 36 years old had a heart attack.”
VIDEO:
B-ROLL
GFX/JAMA Cover
Pan of map of Pakistan, India
AUDIO:
A NEW STUDY IN JAMA, THE JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION, CONFIRMS THAT PEOPLE FROM INDIA AND OTHER SOUTH ASIAN COUNTRIES DO HAVE HEART ATTACKS EARLIER.
VIDEO:
SOT/FULL
@ :30
Super: Salim Yusuf, M.D., D.Phil.
McMaster University/Hamilton Health Sciences
Runs :09
AUDIO:
“The age of 53 or 54 is the mean age in South Asians for heart attack, whereas it’s about 58 or 59 in other parts of the world.”
VIDEO:
B-ROLL
Dr. Yusuf walking into office
Looking at study on computer
Starting at “It also” man smoking
Obese woman at “lack of exercise” through “poor diet”
Man walking outside
AUDIO:
BUT WHY? DR. SALIM (sa-LEEM) YUSUF (YOU-suf) OF MCMASTER UNIVERSITY AND HAMILTON HEALTH SCIENCES IN ONTARIO, CANADA, WAS PART OF THE WORLDWIDE STUDY. IT ALSO IDENTIFIED RISK FACTORS FOR HEART DISEASE, SUCH AS SMOKING, LACK OF EXERCISE, AND POOR DIET. GENERALLY, THE SAME RISK FACTORS FOR PEOPLE OF ANY ETHNICITY. BUT…
VIDEO:
B-ROLL
Thomas having blood drawn
Blood going into vials
More echocardiogram at “more complicated”
AUDIO:
IN OTHER WORDS, THIS BLOOD TEST CAN GIVE DOCTORS AND PATIENTS INFORMATION TO HELP IDENTIFY PATIENTS AT HIGHEST RISK FOR PROBLEMS.
VIDEO:
SOT/FULL
Salim Yusuf, M.D., D.Phil.
McMaster University/Hamilton Health Sciences
Runs :14
AUDIO:
“The reason why South Asians get heart disease at an earlier age is because they have a higher proportion of people with bad cholesterol and less good cholesterol.”
VIDEO:
B-ROLL
Dr. Yusuf taking Jacob’s blood pressure
Cooked veggies/brown curry dish
Fried cauliflower
Younger man crossing street
AUDIO:
HE SAYS THIS IS PROBABLY BIOLOGICAL, THOUGH POOR DIET DOESN’T HELP. DR. YUSUF SAYS IN DISHES LIKE CURRIES, VEGGIES ARE OFTEN COOKED SO LONG THEY LOSE HEALTH BENEFITS. AND THESE HABITS FOLLOW SOUTH ASIANS WHEN THEY EMIGRATE ELSEWHERE.
VIDEO:
SOT/FULL
Salim Yusuf, M.D., D.Phil.
McMaster University/Hamilton Health Sciences
Runs :12
AUDIO:
“I think South Asian immigrants who have come to North America are at even greater risk of heart disease compared to those living in their home countries and the reason for this is that they’re even more urbanized.”
VIDEO:
B-ROLL
Fresh fruits and veggies
Person exercising
Dr. Yusuf with Jacob
AUDIO:
SO HIS ADVICE: EAT HEALTHY FOODS, GET EXERCISE, DON’T SMOKE AND DO GET CHECKED OUT BY A DOCTOR.
VIDEO:
SOT/FULL
Salim Yusuf, M.D., D.Phil.
McMaster University/Hamilton Health Sciences
Runs :06
AUDIO:
“All these are good general advice that we give anybody, but in South Asians they matter even more.”
VIDEO:
B-ROLL
Younger man crossing street with child
AUDIO:
THIS IS MAVIS PRALL WITH THE JAMA REPORT.
