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October 12, 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
ARCHIVES OF INTERNAL MEDICINE NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, October 12, 2009)
ARCHIVES OF NEUROLOGY NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, October 12, 2009)
ARCHIVES OF OPHTHALMOLOGY NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, October 12, 2009)
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. 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), MONDAY, October 12, 2009
Healthy Neighborhoods May Be Associated With Lower Diabetes Risk
CHICAGO—Individuals living in neighborhoods conducive to physical activity and providing access to healthy foods may have a lower risk of developing type 2 diabetes in a five-year period, according to a report in the October 12 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. "The worldwide epidemic of type 2 diabetes mellitus is largely driven by the combined rise in obesity, intake of energy-dense or nutrient-poor foods and physical inactivity," the authors write as background information in the article. Interventions to reduce risk on the individual level—including surgery, medication and behavior change—have had mixed results. Large-scale behavior change may be necessary to reverse the diabetes epidemic, but such a change is difficult to achieve and may be unsustainable if the surrounding environment is not supportive. Amy H. Auchincloss, Ph.D., M.P.H., of Drexel University School of Public Health, Philadelphia, and colleagues studied 2,285 adults age 45 to 84 who were initially examined between 2000 and 2002. Study participants were from three of the sites in the Multi-Ethnic Study of Atherosclerosis (MESA) for which neighborhood level data were obtained: Baltimore; Forsyth County, N.C.; and New York City/Bronx. Blood glucose levels were obtained from study participants at baseline and at three follow-up examinations, during which other individual characteristics also were assessed (including diet, body mass index [BMI] and physical activity levels). Measures of neighborhood resources were obtained from a separate assessment, the Community Survey, in which other residents of the same neighborhoods (defined as the area within a 20-minute walk or a mile from their homes) rated the suitability of their environment for physical activity and access to healthy foods. For instance, they were asked if it was pleasant or easy to walk in their neighborhood, and whether a large, high-quality selection of fruits, vegetables and other low-fat foods was available. Scores for physical activity and healthy foods were calculated for each neighborhood on scales of one to five (with five representing the healthiest areas). Over a median (midpoint) of five years of follow-up, 233 of the 2,285 participants (10.2 percent) developed diabetes. Average neighborhood scores were 3.68 for physical activity and 3.36 for healthy foods. "Better neighborhood resources, determined by a combined score for physical activity and healthy foods, were associated with a 38 percent lower incidence of type 2 diabetes," the authors write. This was similar to the reduction in risk observed among individuals whose BMI was five points lower. "The association remained statistically significant after further adjustment for individual dietary factors, physical activity level and body mass index." The increasing prevalence of type 2 diabetes in the past 30 years makes it urgent to identify environmental features that may mitigate risk, the authors conclude. "Current efforts to foster health-promoting environments include designing and modifying physical environments, such as zoning residential neighborhoods to require safe sidewalks, creating parks and attractive public green spaces and improving public transportation so that residents rely less on their cars; supporting fresh-food farmers' markets in low-income, urban neighborhoods; and assisting stores in those neighborhoods in improving their selection of healthy foods," they write.
"There is unlikely to be a panacea for the obesity epidemic and rising epidemic of type 2 diabetes. However, altering our environments so that healthier behaviors and lifestyles can be easily chosen may be one of the key steps in arresting and reversing these epidemics."
Editor's Note: This research was supported by contracts from the National Heart, Lung and Blood Institute, National Institutes of Health. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc. Editorial: Neighborhood May Be a Modifiable Risk Factor for Diabetes
"Given the challenges of mounting an intervention at the individual level, it is heartening to read a study suggesting that it may be possible to decrease the incidence of diabetes by modifying the environment," writes Mitchell H. Katz, M.D., of the San Francisco Department of Public Health, in an accompanying editorial.
"Unfortunately, in most developed countries today, the environment offers few opportunities for exercise, and highly processed foods are more plentiful than fresh vegetables and raw grains," Dr. Katz writes. "While causality cannot be proven, the increase in obesity and type 2 diabetes in developed countries tracks with these environmental changes. If we are to decrease the rates of type 2 diabetes, we need to change the environment in ways that make it easy for people to exercise and eat right as part of their daily routine."
Editor's Note: Dr. Katz has served as a paid independent consultant for Health Management Associates and has received reimbursement for travel expenses from them. Please see the article for additional information, including 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.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, October 12, 2009
Investigation of Contaminated Heparin Syringes Highlights Medication Safety Issues
CHICAGO—An outbreak of bloodstream infections appears to have been caused by the contamination of pre-filled heparin and saline syringes made by a single company, according to a report in the October 12 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. The subsequent investigation revealed that the company was not in compliance with safety regulations and identified challenges and areas for improvement in medication monitoring systems. Between October 2007 and February 2008, the Centers for Disease Control and Prevention (CDC) received reports of clusters of bloodstream infections caused by the bacteria Serratia marcescens at health care facilities in several states, according to background information in the article. Based on initial information from facilities in Texas and Illinois, the investigation into the cause of the outbreak focused on syringes pre-filled with the blood thinner heparin and saline from one company (company X). David Blossom, M.D., of the Centers for Disease Control and Prevention, Atlanta, and colleagues report that the company was able to provide records for other facilities that had received the same syringes. The CDC contacted these recipients and posted requests on e-mail distribution lists to solicit additional infection case reports. Culture specimens were taken from unopened pre-filled heparin and saline syringes at facilities reporting infections as well as at company X. A total of 162 S. marcescens bloodstream infections in nine states were reported among patients at facilities using syringes from the same company. Cultures of unopened pre-filled heparin and saline syringes manufactured by this company grew S. marcescens. Of 83 blood samples that contained S. marcescens submitted to the CDC from seven states, 70 (84 percent) contained bacteria genetically related to that grown from the pre-filled syringes. "To ensure the sterility of manufactured medical products, companies must adhere to the U.S. Food and Drug Administration's Good Manufacturing Practices [GMPs], a comprehensive body of regulations that govern all aspects of production," the authors write. "An onsite inspection of the manufacturer by the FDA revealed poor compliance with the FDA's GMPs and quality system regulations. Within days of this inspection, company X discontinued production of all medical products." The company also issued a voluntary national recall of the pre-filled syringes. "Close collaboration among federal agencies, public health authorities and clinicians was critical to the identification of the cause of this outbreak," the authors conclude. "In the course of the investigation, we also identified several challenges to medical product tracking that should be addressed promptly so that disease outbreaks caused by exposure to contaminated medications can be dealt with more efficiently in the future." For example, a large number of distributors acted as intermediaries between the manufacturer and the health care facilities that used the products, and none of the syringes bore company X's name on the label, but rather had the names of subsidiaries or different companies.
In addition, some batches of the syringes were contaminated whereas others were not; this intermittent nature made identifying the source of the outbreak more difficult. This suggests that investigations of potential contamination must include both epidemiologic and laboratory components, since initial laboratory tests may prove inconclusive.
Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc. Editorial: FDA Must Be Given Tools to Ensure Drug Safety
"The analysis accompanying this commentary describes a serious contamination of heparin marketed in pre-filled syringes," writes William K. Hubbard, B.A., M.A., former FDA associate commissioner, in an accompanying editorial. "Subsequent FDA investigation determined that the manufacturer had failed to adhere to the agency's quality control requirements. But an even more notorious recent case of a drug manufacturing problem was that of imported heparin believed to have contributed to dozens of deaths and an unknown number of injuries."
"We simply must, as a nation, recognize that we cannot reverse this trend toward globalization, that the solution to a safe drug supply is a strong FDA, not reliance on foreign governments," Mr. Hubbard concludes. "Throughout the 20th century, the FDA was a major contributor to our overall societal ‘safety net' and came through for us many times when challenged with threats to our food and drug supply. Now, when we need them more than ever, we must be there to help the FDA," through measures such as increased funding and staffing.
Editor's Note: Please see the article for additional information, including 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.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, October 12, 2009
Declines in Other Thinking and Learning Skills May Precede Memory Loss in Alzheimer's Disease
CHICAGO—Cognitive abilities other than memory, including visuospatial skills needed to perceive relationships between objects, may decline years prior to a clinical diagnosis in patients with Alzheimer's disease, according to a report in the October issue of Archives of Neurology, one of the JAMA/Archives journals. "Recent studies have focused on identifying the beginning of the transition from healthy aging to dementia," the authors write as background information in the article. "As new interventions become available, it will become important to identify the disease as early as possible." Loss of episodic memory—remembering events in one's life that can be explicitly stated—is commonly linked to Alzheimer's disease, but it is not the only aspect of cognition (thinking, learning and memory) that is affected. David K. Johnson, Ph.D., of the University of Kansas, Lawrence, and colleagues assessed 444 individuals who did not have dementia when they were enrolled in the study, between 1979 and 2006. Upon enrolling, each participant underwent a clinical evaluation and a psychometric assessment including tests of four cognitive factors: global cognition, verbal memory, visuospatial skill and working memory. Participants were then evaluated at least one additional time before November 2007. Over an average follow-up of 5.9 years, 134 individuals developed dementia and 310 did not; 44 with dementia died and underwent brain autopsies that confirmed a diagnosis of Alzheimer's disease. Using data from the psychometric assessments, the researchers constructed models to evaluate the decline in various cognitive areas before individuals were diagnosed with dementia. "A novel finding was that visuospatial abilities demonstrated an inflection point [sudden change to a steeper slope of decline] three years before clinical diagnosis," the authors write. Declines in overall cognitive abilities followed in the next year, whereas inflection points for verbal and working memory were not seen until one year before clinical diagnosis. Similar results occurred in only the subgroup of individuals with Alzheimer's disease diagnosis confirmed by autopsy. "There are several implications of this study," the authors conclude. "Some of the earliest signs of preclinical disease may occur on tests of visuospatial and speeded psychomotor skills. Furthermore, the greatest rate of preclinical decline may occur on executive and attention tasks. These findings suggest that research into early detection of cognitive disorders using only episodic memory tasks, such as word lists or paragraph recall, may not be sensitive to either all of the earliest manifestations of disease or the most rapidly changing domain."
"In summary, converging longitudinal evidence suggests that after a sharp departure from the relatively flat course of normal aging there is a preclinical period in Alzheimer's disease with insufficient cognitive decline to warrant clinical diagnosis using conventional criteria but that can be seen with longitudinal data from multiple domains of cognition and not just memory," they conclude.
Editor's Note: This study was supported by grants from the National Institute on Aging, National Institutes of Health. 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.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, October 12, 2009
Urate in Blood and Spinal Fluid May Predict Slower Decline in Patients With Parkinson's Disease
CHICAGO—Higher concentration of urate (an antioxidant) in the blood and spinal fluid of patients with early Parkinson's disease is associated with slower rates of clinical decline, according to a report posted online today that will appear in the December print issue of Archives of Neurology, one of the JAMA/Archives journals. Urate is an antioxidant that occurs naturally in the blood as an end product of normal metabolism. Antioxidants counteract oxygen-related cell damage, thought to contribute to the neurodegenerative process in Parkinson's disease, according to background information in the article. Therefore, urate and similar substances may provide a defense against the development and progression of Parkinson's disease. Previous studies have demonstrated that healthy individuals with higher blood urate concentrations have a lower risk of developing the condition. Alberto Ascherio, M.D., Dr.P.H., of Harvard School of Public Health and Harvard Medical School, Boston, and colleagues studied 800 individuals with early Parkinson's disease enrolled in a clinical trial of two medications for the condition. At the beginning of the study, between 1987 and 1988, urate levels were measured in the blood of 774 participants. Cerebrospinal fluid also was collected from 713 of them and then after twenty years of freezer storage was analyzed for urate. After two years of follow-up, 369 (48 percent) of 774 patients with blood urate measurements became disabled enough to begin therapy with levodopa—a medication used to treat symptoms of Parkinson's disease. The one-fifth of patients with the highest levels of blood urate (more than 6.2 milligrams per deciliter) had a 36 percent reduced risk of disease progression to this point when compared with the one-fifth who had the lowest levels (3.9 milligrams per deciliter or less). Among the 713 participants with cerebrospinal fluid urate levels, 342 (48 percent) progressed to a level of disability requiring levodopa therapy. Concentration of urate in the cerebrospinal fluid also was inversely related to the likelihood of disease progression.
"Taken together, these data establish urate as the first molecular predictor of clinical progression in Parkinson's disease and provide a rationale for investigating the possibility that a therapeutic increase of urate in patients with Parkinson's disease might act favorably to slow the disease course," the authors write. Urate levels can be elevated through diet, by increasing intake of fructose (sugars found in fruits) or purines (found in many meats, foods with yeast and alcoholic beverages). Levels could also be increased pharmacologically with inosine, a precursor to urate, which is being investigated as a therapy for multiple sclerosis as well as in a new clinical trial for Parkinson's disease.
Editor's Note: This work was supported by grants from the National Institutes of Health, a grant from the U.S. Department of Defense, and by the RJG Foundation, the Beeson Scholars/Hartford Collaborative Research program of the American Federation for Aging Research and a data-mining research award from the Parkinson Disease Foundation and the Parkinson Study Group. 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.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, October 12, 2009
Noncorrectable Vision Problems Associated With Shorter Lifespan in Older Adults
CHICAGO—Visual problems that cannot be corrected are associated with increased risk of death among individuals between the ages of 49 and 74, and all visual impairments may be associated with the risk of death in older adults, according to a report in the October issue of Archives of Ophthalmology, one of the JAMA/Archives journals. Visual impairment has been associated with a higher risk of death as well as factors that may lead to increased death such as unintentional injury, depression, lower body mass index (BMI), reduced walking speeds, increased risk of falls, self-reported difficulty in physical activity, cardiovascular disease, dementia and cancer, according to background information in the article. "Correction for these 'confounders' has been found to attenuate the association between visual impairment and mortality, but the mechanisms behind the association between visual impairment and mortality remain to be determined." Michael J. Karpa, M.B.B.S., B.Sc., of Westmead Millennium Institute, Sydney, Australia, and colleagues used data from the Blue Mountains Eye Study, which examined visual impairment in 3,654 participants age 49 and older between 1992 and 1994 and after five and ten years, to evaluate the relationship between visual impairment and death risk among older individuals. At baseline, participants with noncorrectable visual impairment were more likely to be female, age 75 and older and underweight. Those with correctable visual impairment were more likely to be age 75 and older, but had no difference in proportions of women or BMI. Thirteen years after baseline, 1,273 participants had died. A higher risk of dying was associated with noncorrectable visual impairment, with a stronger association for participants younger than age 75. The analyses "revealed greater effects of noncorrectable visual impairment on mortality risk, with both direct and indirect effects," the authors write. "Of mortality risk markers examined, only disability in walking demonstrated a significant indirect pathway for the link between visual impairment and mortality."
"In conclusion, this study reaffirms that visual impairment is associated with an increased risk of all-cause mortality," the authors write. "Disability in walking may represent an important indirect pathway to mortality for persons with visual impairment, and adjusting for this factor in statistical analysis may overadjust for the indirect effect of visual impairment on mortality risk. The impact of visual impairment on mortality may in fact be greater than that reported from previous studies that have used traditional statistical models."
Editor's Note: The Blue Mountains Eye Study was supported by National Health and Medical Research Council (Australia) grants. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, October 12, 2009
More Infants Surviving Pre-Term Births Results in Higher Rates of Eye Problems
CHICAGO—As more extremely pre-term infants survive in Sweden, an increasing number of babies are experiencing vision problems caused by abnormalities involving the retina, according to a report in the October issue of Archives of Ophthalmology, one of the JAMA/Archives journals. "Retinopathy of prematurity [abnormal development of blood vessels in the retina] remains an important cause of childhood blindness and visual impairment throughout the world," the authors write as background information in the article. "During the last decade, neonatal care has changed with an increase in centralization, implementation of new therapies and provision of intensive care for infants of extremely low gestational age. These changes have contributed to an increasing population of survivors in neonatal intensive care units today. The incidence of retinopathy of prematurity in these extremely preterm infants is, therefore, unknown." Dordi Austeng, M.D., of University Hospital, Uppsala, Sweden, and Trondheim University Hospital, Trondheim, Norway, and colleagues studied Swedish infants born before 27 weeks' gestation between 2004 and 2007. Infants were screened for retinopathy of prematurity beginning at five weeks after birth and were treated for the condition according to established guidelines. During the study, 506 of 707 infants survived until the first eye examination. Of these, 368 (72.7 percent) had retinopathy of prematurity, including 37.9 percent with mild cases and 34.8 percent whose condition was severe. A total of 99 (19.6 percent) were treated. Gestational age was more closely associated with the development of retinopathy of prematurity than was birth weight. "The incidence was reduced from 100 percent in the five infants born at 22 weeks' gestation to 56 percent in those born at 26 completed weeks," the authors write. "In addition, the risk of retinopathy of prematurity declined by 50 percent for each week of gestational age at birth in the cohort." Direct comparisons with previous studies are difficult, but most have found much lower incidences of severe retinopathy of prematurity, the authors note. For instance, a Belgian study reported a 25.5 percent incidence among infants born at 27 weeks' gestation or earlier and an Austrian study observed a 16 percent lower rate, compared with the 34.8 percent incidence in the current findings.
"The higher incidence of retinopathy of prematurity in the present study may be because of the higher proportion of infants born in the earliest weeks of gestation (i.e., 11.5 percent of infants in weeks 22 to 23 vs. 0 percent to 6 percent in the other studies)," the authors write. "These extremely premature infants, who previously did not survive, are probably especially vulnerable and prone to develop complications such as retinopathy of prematurity."
Editor's Note: This study was supported by the Birgit and Sven Håkan Olsson Foundation, the Evy and Gunnar Sandberg Foundation, Kronprinsessan Margarethas Arbetsnämnd för synskadade, the Norwegian Association of the Blind and Partially Sighted, Stiftelsen Solstickan and the Swedish Association of the Visually Impaired. 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. |
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