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August 11, 2009JAMA news releases are made available to the public after 3 pm US Central time on the first 4 Tuesdays of each month. The Archives of 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 CONTENTS
JAMA NEWS RELEASES
(Embargoed for Release: 3 p.m. CT Tuesday, August 11, 2009)
JAMA REPORT (VIDEO SCRIPT)
INFORMATION CONTAINED IN THESE NEWS RELEASES IS PROTECTED BY COPYRIGHT. JOURNAL ATTRIBUTION IS REQUIRED. JOURNALISTS CAN NOW ACCESS EMBARGOED JAMA/ARCHIVES STUDIES ON-LINE. Go to www.jamamedia.org for more information and to apply for access. TV Note: PLEASE NOTE, FEED TIMES ARE NOW 15 MINUTES. This week's JAMA Report video is on the effect of a Mediterranean-type diet and physical activity on the risk of Alzheimer disease. The report will be fed Tuesday, August 11, from 9:00 - 9:15 a.m. ET and 2:00 - 2:15 p.m. ET, on Galaxy 28 (C-Band), Transponder 19, downlink frequency: 4080 vertical, audio 6.2/6.8. For more information, call 312/464-JAMA. The JAMA Report video is also now available on Pathfire every Tuesday. Please look for the JAMA Report "channel". Save the Date: The Sixth International Congress on Peer Review and Biomedical Publication will be held September 10-12 in Vancouver, Canada. New research will be presented on peer review and the other processes used to evaluate and disseminate medical information. For program and registration information, go to www.jamamedia.org and click on the Events tab. Please Note: The FOR THE MEDIA website now has a search feature to enable media to find previous JAMA/Archives news releases on specific medical topics. This search feature link is located on the home page at www.jamamedia.org EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), Tuesday, August 11, 2009
High Adherence to Mediterranean-Type Diet, Increased Physical Activity Associated With Reduced Risk of Alzheimer Disease
CHICAGO—Elderly individuals who had a diet that included higher consumption of fruits, vegetables, legumes, cereal and fish and was low in red meat and poultry and who were physically active had an associated lower risk of Alzheimer disease, according to a study in the August 12 issue of JAMA. In a second study, higher adherence to a Mediterranean diet was associated with slower cognitive decline, but was not associated with a decreased risk of dementia. Research regarding the effect physical activity can have on the risk of Alzheimer disease (AD) or dementia has shown mixed results, as has the effect of dietary habits. Their combined association has not been investigated, according to background information in the article. Nikolaos Scarmeas, M.D., of Columbia University Medical Center, New York, and colleagues examined the association between physical activity and risk of AD and also the effect of physical activity and adherence to a Mediterranean-type diet on AD risk. The study included 2 groups that consisted of 1,880 community-dwelling elderly residents of New York city without dementia at the start of the study, for whom there was both diet and physical activity information available. Standardized neurological and neuropsychological measures were administered approximately every 1.5 years from 1992 through 2006. The participants received measurements of their adherence to a Mediterranean-type diet (scale of 0-9; categorized as low, middle, or high) and their physical activity (sum of weekly participation in various physical activities, weighted by the type of physical activity [light, moderate, vigorous]; categorized into no physical activity, some, or much, also low or high), separately and combined. A higher score for diet was obtained with higher consumption of fruits, vegetables, legumes, cereals, and fish; lower consumption of meat and dairy products; a higher ratio of monounsaturated fats to saturated fats and mild to moderate alcohol consumption. Individuals were followed up for an average of 5.4 years, during which a total of 282 developed AD. In considering only physical activity, the researchers found that more physical activity was associated with lower risk for developing AD. "Compared with physically inactive individuals, report of some physical activity was associated with a 29 percent to 41 percent lower risk of developing AD, while report of much physical activity was associated with a 37 percent to 50 percent lower risk," the authors write. When considered simultaneously, both physical activity and Mediterranean diet adherence were significantly associated with AD incidence. According to the researchers, "Belonging to the middle diet adherence tertile was associated with a 2 percent to 14 percent risk reduction, while belonging to the highest diet adherence tertile was associated with a 32 percent to 40 percent reduced risk. Similarly, compared with individuals with no physical activity, individuals reporting some physical activity had a 25 percent to 38 percent lower risk for AD, while individuals reporting much physical activity had a 33 percent to 48 percent lower risk for AD." The authors also write, "Compared with individuals with low physical activity plus low adherence to a diet (absolute AD risk, 19 percent), high physical activity plus high diet adherence was associated with a 35 percent to 44 percent relative risk reduction (absolute AD risk, 12 percent). ... Absolute AD risks declined from 21 percent in the group with no physical activity plus low diet adherence to 9 percent in the group with much physical activity plus high diet adherence."
"In summary, our results support the potentially independent and important role of both physical activity and dietary habits in relation to AD risk. These findings should be further evaluated in other populations."
Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc. Higher Adherence to Mediterranean Diet Associated With Slower Cognitive Decline
In an examination of the association between adherence to a Mediterranean-type diet and cognitive performance and risk of dementia, researchers found that high adherence to the diet was associated with slower decline in some measures of cognitive function but was not associated with decreased risk for dementia, according to a study in the August 12 issue of JAMA. Higher adherence to a Mediterranean-type diet is linked to lower risk for mortality and chronic diseases, and "might also have protective effects against cognitive decline in older individuals, because it combines several foods and nutrients potentially protective against cognitive dysfunction or dementia, such as fish, monounsaturated fatty acids, vitamins B12 and folate, antioxidants (vitamin E, carotenoids, flavonoids), and moderate amounts of alcohol," the authors write. But its association with cognitive decline has been unclear. Catherine Féart, Ph.D., of the Université Victor Ségalen Bordeaux 2, Bordeaux, France, and colleagues examined whether adherence to a Mediterranean diet was associated with change in cognitive performance and with lower risk of all-cause dementia or Alzheimer disease. The study included 1,410 individuals (age 65 years or older) from Bordeaux, France, who were part of the Three-City cohort in 2001-2002 (a study of vascular risk factors of dementia) and were re-examined at least once over 5 years. Adherence to a Mediterranean diet (scored as 0 to 9) was computed from a food frequency questionnaire and 24-hour recall. Cognitive performance was assessed on 4 neuropsychological tests: the Mini-Mental State Examination (MMSE), Isaacs Set Test (IST), Benton Visual Retention Test (BVRT), and Free and Cued Selective Reminding Test (FCSRT). New cases of dementia (n = 99) were validated by an independent expert committee of neurologists. After adjusting for age, sex, education, marital status, energy intake, physical activity, depressive symptomatology, taking 5 medications/day or more, apolipoprotein E genotype, cardiovascular risk factors, and stroke, the researchers found that higher Mediterranean diet score was associated with fewer MMSE errors. But performance on the IST, BVRT, or FCSRT over time was not significantly associated with Mediterranean diet adherence, especially in those who remained free from dementia over 5 years. Mediterranean diet adherence was not associated with the risk for incident dementia, although the statistical strength of the data to detect a difference was limited.
"The Mediterranean diet pattern probably does not fully explain the better health of persons who adhere to it, but it may contribute directly. A Mediterranean diet also may indirectly constitute an indicator of a complex set of favorable social and lifestyle factors that contribute to better health. Further research is needed to allow the generalization of these results to other populations and to establish whether a Mediterranean diet slows cognitive decline or reduces incident dementia in addition to its cardiovascular benefits," the authors conclude.
Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc. Editorial: Mediterranean Diet and Late-Life Cognitive Impairment
In an accompanying editorial, David S. Knopman, M.D., of Mayo Clinic, Rochester, Minn., comments on the studies in this week's JAMA on diet, physical activity and risk of dementia and Alzheimer disease. "A variety of approaches to mitigating cerebrovascular disease in midlife exist, including diet, exercise, treatment of hypertension, treatment of diabetes, avoidance of obesity, and avoidance of smoking. The findings of Scarmeas et al and Féart et al fit into a larger and potentially optimistic view of prevention of late-life cognitive impairment through application, at least by midlife, of as many healthy behaviors as possible, including diet. Based on these 2 studies, diet may play a supporting role, but following a healthy diet does not occur in isolation."
"The scientific value of these studies cannot be disputed, but whether and how they can or should be translated into recommendations for the public is the question."
Editor's Note: Please see the article for additional information, including financial disclosures, funding and support, etc. For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org. EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), Tuesday, August 11, 2009
Aspirin Use After Colorectal Cancer Diagnosis Associated With Improved Survival
CHICAGO—Men and women who were diagnosed with colorectal cancer and began regular use of aspirin had a lower risk of overall and colorectal cancer death compared to patients not using aspirin, according to a study in the August 12 issue of JAMA. Numerous prospective, observational studies demonstrate that regular aspirin use is associated with a lower risk of colorectal adenoma (a benign tumor) or cancer. Aspirin is likely, at least in part, to prevent colorectal neoplasia (tumor growth) through inhibition of cyclooxygenase-2 (COX-2; an enzyme), which promotes inflammation and cell proliferation, and is overexpressed in the majority of human colorectal cancers, according to background information in the article. However, the influence of aspirin on survival after diagnosis of colorectal cancer has been unknown. Andrew T. Chan, M.D., M.P.H., of Massachusetts General Hospital and Harvard Medical School, Boston, and colleagues studied the association between aspirin use and survival among 1,279 men and women with nonmetastatic (stage I, II, and III) colorectal cancer who were participating in 2 large prospective cohort studies (Nurses' Health Study [NHS] and the Health Professionals Follow-up Study [HPFS]) that were initiated (in 1980 and 1986, respectively) prior to cancer diagnosis and followed up through June 1, 2008. "Within these cohorts, we previously have demonstrated that regular aspirin use was associated with a reduction in the subsequent risk of developing an initial primary colorectal cancer, particularly tumors with COX-2 overexpression. Because these participants have provided biennially updated data on aspirin use, we had a unique opportunity to extend these findings by examining the influence of prediagnosis and postdiagnosis aspirin use on the survival of patients with established colorectal cancer," the authors write. For participants who were alive through the end of follow-up, the median (midpoint) time of follow-up from date of diagnosis was 11.8 years. There were 193 total deaths (35 percent) and 81 colorectal cancer-specific deaths (15 percent) among 549 participants who regularly used aspirin after colorectal cancer diagnosis, compared with 287 (39 percent) total and 141 (19 percent) colorectal cancer-specific deaths among 730 participants who did not use aspirin. For the entire cohort, the overall 5-year survival was 88 percent for participants who used aspirin compared with 83 percent for those who did not. The corresponding 10-year survival rates were 74 percent and 69 percent. Regular use of aspirin after diagnosis was associated with a significant reduction in risk of colorectal cancer-specific death and a reduction in overall mortality. Compared with nonusers, regular aspirin use after diagnosis was associated with a 29 percent lower risk for colorectal-specific mortality and a 21 percent lower risk for overall mortality. Because the prognosis among stage I participants is generally favorable, the researchers also examined the influence of aspirin use among those diagnosed with stage II or III disease and observed similar results. Among the 719 participants who did not use aspirin before diagnosis, initiation of use postdiagnosis was associated with a 47 percent lower risk for colorectal cancer-specific mortality and a 32 percent lower risk of overall mortality. In contrast, among participants who were using aspirin before diagnosis, continuation of aspirin use postdiagnosis was not associated with a significant reduction in colorectal cancer-specific survival or overall survival. Among participants with COX-2-positive tumors, regular aspirin use after diagnosis was associated with a 61 percent lower risk of colorectal cancer-specific death and 38 percent lower risk of overall mortality, whereas postdiagnosis aspirin use was not associated with lower risk of either colorectal cancer-specific or overall mortality for those with COX-2-negative tumors. "This supports the hypothesis that COX-2-positive tumors may be relatively sensitive to the anticancer effect of aspirin, whereas COX-2-negative tumors may be relatively aspirin-resistant. Moreover, it potentially explains the observation that the benefit of postdiagnosis aspirin use on patient survival was not apparent among patients who used aspirin prior to cancer diagnosis," the researchers note.
"These results suggest that aspirin may influence the biology of established colorectal tumors in addition to preventing their occurrence. Our data also highlight the potential for using COX-2 or related markers to tailor aspirin use among patients with newly diagnosed colorectal cancer. Nonetheless, because our data are observational, routine use of aspirin or related agents as cancer therapy cannot be recommended, especially in light of concerns over their related toxicities, such as gastrointestinal bleeding. Further studies among patients with colorectal cancer, including placebo-controlled trials of aspirin or related agents as adjuncts to other routine therapies, are required."
Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc. Editorial: Aspirin as Adjuvant Therapy for Colorectal Cancer - A Promising New Twist for an Old Drug
Alfred I. Neugut, M.D., Ph.D., of Columbia University, New York, writes in an accompanying editorial that the results of this study are encouraging.
"In the study by Chan et al, the survival benefits of aspirin were similar in patients who received standard adjuvant chemotherapy and those who did not, and in patients with stage I and stage II disease as well as those who had stage III disease at diagnosis. Thus, aspirin may have the potential to be useful as adjuvant therapy not just for locally advanced disease but for early-stage patients as well. Further studies are needed to confirm and extend these findings, and should also investigate the use of aspirin as an agent in individuals with metastatic disease."
Editor's Note: Please see the article for additional information, including financial disclosures, funding and support, etc. For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org. EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), Tuesday, August 11, 2009
Study Examines Decrease in Delivery-Related Rate of Death of Infants Born at Term
CHICAGO—During about the last 20 years, the risk of delivery-related death at birth or shortly thereafter for term infants has decreased nearly 40 percent in Scotland, with the largest contributing factor being a decrease in the number of deaths caused by a lack of oxygen for the baby during the childbirth process, according to a study in the August 12 issue of JAMA. Rates of obstetric intervention in labor, including cesarean delivery, have increased significantly in most developed countries. "It is, however, unclear if this has been paralleled by decreased rates of perinatal [pertaining to the period immediately before and after birth] and neonatal death associated with complications of labor at term," the authors write. Dharmintra Pasupathy, M.B., Ch.B., M.Sc., of the University of Cambridge, England, and colleagues used data from more than 1 million births at term during a 20-year period in Scotland to determine the trend and factors associated with delivery-related perinatal death. The study included data from a registry of births (Scottish Morbidity Record 02) and a registry of perinatal deaths (Scottish Stillbirth and Infant Death Survey) between 1988 and 2007 and included all single infant births in a cephalic (head) presentation at term (n = 1,012,266), excluding those with perinatal death due to congenital anomaly or antepartum (before birth) stillbirth. There were 719 delivery-related perinatal deaths (0.07 percent) during the study period, which included 219 intrapartum stillbirths (defined as "intrauterine fetal death occurred following the onset of labor but before birth"; 30.5 percent) and 500 neonatal deaths (defined as "death during the first 4 weeks of life in a liveborn infant"; 69.5 percent). Of these perinatal deaths, 432 (60.1 percent) were attributed to intrapartum anoxia (lack of oxygen occurring during delivery) and 287 (39.9 percent) were attributed to other causes. The absolute risk of delivery-related perinatal death in the population was 7.1 per 10,000 births. The incidence of perinatal death attributed to intrapartum anoxia (4.3 per 10,000 births) was higher than the incidence of perinatal death attributed to other causes (2.8 per 10,000 births). When modeled between 1988 and 2007, there was a decrease in the risk of delivery-related perinatal death from 8.8 to 5.5 per 10,000 births, a 38 percent decrease. When analyzed by the cause of death, there was a statistically significant decrease in the incidence of death attributed to intrapartum anoxia from 5.7 to 3.0 per 10,000 births (a 48 percent decrease), but no statistically significant decrease in the incidence of deaths attributed to other causes. The magnitude of the decrease in the incidence of deaths attributed to intrapartum anoxia was comparable between intrapartum stillbirth (2.6 to 1.1 per 10,000 births; a 60 percent decrease) and neonatal death (3.1 to 1.9 per 10,000 births; a 38 percent decrease). Adjustment for maternal, fetal, or obstetric characteristics did not reduce the magnitude of decrease in the risk of delivery-related perinatal death or in the subgroup attributed to intrapartum anoxia.
"The key finding of our analysis is that rates of death ascribed to intrapartum anoxia in term infants declined in Scotland between 1988 and 2007," the authors write. "The pattern of the decline suggests that this was primarily due to a reduced number of severely anoxic infants rather than improved neonatal resuscitation. The change was paralleled by increased rates of cesarean delivery, but there is no direct evidence supporting a causal association between the 2 trends."
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 JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org.
JAMA REPORTS
VIDEO: Windows Media | Quicktime
EATING A MEDITERRANEAN-TYPE DIET AND STAYING ACTIVE BOTH LINKED TO A LOWER RISK FOR ALZHEIMER'S DISEASE
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