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August 10, 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, August 10, 2009)
ARCHIVES OF NEUROLOGY NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, August 10, 2009)
ARCHIVES OF OPHTHALMOLOGY NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, August 10, 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, August 10, 2009
Breastfeeding Associated With Reduced Risk of Breast Cancer Among Women With Family History
CHICAGO—Women with a family history of breast cancer appear to have a lower risk of developing the disease before menopause if they have ever breastfed a child, according to a report in the August 10/24 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. More women around the world develop breast cancer than any other malignancy, according to background information in the article. Established risk factors include a family history, beginning menstruation at an early age and not having children or having a first child at a late age. Alison M. Stuebe, M.D., M.Sc., then of Brigham and Women's Hospital and Harvard Medical School, Boston, and now of the University of North Carolina at Chapel Hill, and colleagues used information from 60,075 women who had given birth and who participated in the Nurses' Health Study between 1997 and 2005. Each woman completed a detailed questionnaire on demographic characteristics, body measurements and lifestyle factors, with follow-up questionnaires every two years. Breastfeeding history was assessed in detail on the 1997 questionnaire, and on each subsequent follow-up the women were asked to report whether they had been diagnosed with breast cancer. Through the end of the study-June 2005-a total of 608 cases of premenopausal breast cancer were diagnosed, at an average age of 46.2 years. Women who had a first-degree relative with breast cancer had a lower risk of developing the disease if they had ever breastfed than if they had never breastfed. The association did not appear to change based on duration of breastfeeding, whether breastfeeding was exclusive or whether the woman experienced amenorrhea (absence of menstruation) as a result. There was no association between breastfeeding and breast cancer among women without a family history. Women who did not breastfeed but used medication to suppress breast milk production also appeared to have a lower risk of breast cancer than women who neither breastfed nor used lactation suppression. This association could be related to disordered involution, or a malfunction in the process by which mammary tissue returns to its pre-pregnant state caused by engorgement and inflammation, the authors note.
"Future studies of interactions among breastfeeding history, family history and genotypes associated with breast cancer risk will be needed to confirm these associations and explore underlying mechanisms," they write. In the meantime, the observed risk reduction compared favorably to that experienced by high-risk women taking hormonal treatments such as tamoxifen, they continue. "Moreover, breastfeeding is associated with multiple other health benefits for both mother and child. These data suggest that women with a family history of breast cancer should be strongly encouraged to breastfeed."
Editor's Note: The Nurses' Health Study II is supported by a Public Health Service grant from the National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services. 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, August 10, 2009
Healthy Lifestyle Habits May Be Associated With Reduced Risk of Chronic Disease
CHICAGO—Four healthy lifestyle factors-never smoking, maintaining a healthy weight, exercising regularly and following a healthy diet-together appear to be associated with as much as an 80 percent reduction in the risk of developing the most common and deadly chronic diseases, according to a report in the August 10/24 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. Cardiovascular disease, cancer and diabetes-chronic diseases that together account for most deaths-are largely preventable, according to background information in the article. "An impressive body of research has implicated modifiable lifestyle factors such as smoking, physical activity, diet and body weight in the causes of these diseases," the authors write. To further describe the reduction in risk associated with these factors, Earl S. Ford, M.D., M.P.H., of the Centers for Disease Control and Prevention, Atlanta, and colleagues assessed data from 23,513 German adults age 35 to 65. At the beginning of the European Prospective Investigation Into Cancer and Nutrition-Potsdam (EPIC-Potsdam) study-between 1994 and 1998-participants completed an assessment of their body weight and height, a personal interview that included questions about diseases, a questionnaire on sociodemographic and lifestyle characteristics and a food frequency questionnaire. Their responses were assessed for adherence to four healthy lifestyle factors: never smoking, having a body mass index lower than 30, exercising for at least three and a half hours per week and following healthy dietary principles (for example, having a diet with high consumption of fruits and vegetables while limiting meat consumption). Follow-up questionnaires were administered every two to three years. Most participants had one to three of these health factors, fewer than 4 percent had zero healthy factors and 9 percent had all four factors. Over an average of 7.8 years of follow-up, 2,006 participants developed new cases of diabetes (3.7 percent), heart attack (0.9 percent), stroke (0.8 percent) or cancer (3.8 percent). After adjusting for age, sex, education level and occupation, individuals with more healthy lifestyle factors were less likely to develop chronic diseases. Participants who had all four factors at the beginning of the study had a 78 percent lower risk of developing any of the chronic diseases during the follow-up period than those who had none of the healthy factors. The four factors were associated with a 93 percent reduced risk of diabetes, 81 percent reduced risk of heart attack, 50 percent reduced risk of stroke and 36 percent reduced risk of cancer. The largest reduction in risk was associated with having a BMI lower than 30, followed by never smoking, at least 3.5 hours of physical activity and then adhering to good dietary principles.
"Our results reinforce current public health recommendations to avoid smoking, to maintain a healthy weight, to engage in physical activity appropriately and to eat adequate amounts of fruits and vegetables and foods containing whole grains and to partake of red meat prudently," the authors write. "Because the roots of these factors often originate during the formative stages of life, it is especially important to start early in teaching the important lessons concerning healthy living."
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.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, August 10, 2009
MRSA May Accompany Hospital Patients Into Home Health Settings
CHICAGO—Infection with methicillin-resistant Staphylococcus aureus (MRSA) appears relatively common among patients discharged from the hospital into home health care, according to a report in the August 10/24 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. In addition, about one-fifth of infected patients may transmit the organism to other people in their households. MRSA is common in hospitals in most countries, and as the incidence of infection increases new patterns of spread are emerging, according to background information in the article. "Thus, in the last decade, community-acquired MRSA strains have caused hospital outbreaks and sometimes replaced older strains previously responsible for hospital-acquired MRSA infections," the authors write. "Conversely, hospital-acquired MRSA strains can spread outside the health care system." Jean-Christophe Lucet, M.D., Ph.D., of Bichat-Claude Bernard Hospital, Assistance Publique-Hôpitaux de Paris, France, and colleagues studied 1,501 adult inpatients in French hospitals who in 2003 and 2004 were screened for MRSA before discharge to home health care. Patients were followed up and screened for clearance of MRSA every three months for one year, and household contacts were also screened for presence of the organism. MRSA was identified in a total of 191 of the 1,501 patients (12.7 percent) before discharge from the hospital to home health care. Of the 148 who were followed up, 75 were found to have cleared the organism within one year. Patients who were more self-sufficient in daily activities appeared more likely to experience clearance of MRSA. The 191 patients with MRSA had 188 household contacts who participated in the study. Of these, 36 (19.1 percent) acquired MRSA, although none developed an infection. Household contacts who were older and who played a role in providing health care for the patient appeared more likely to be colonized with MRSA. "Sharing the same bed or bedroom, in contrast, was not associated with MRSA transmission," the authors write. "Thus, MRSA may be preferentially transmitted to contacts who are at high risk for hand contamination during care procedures."
Because none of the household contacts who acquired MRSA developed an infection, it is unclear whether this transmission represents a serious public health problem, the authors note. However, to prevent spread of the organism, "household contacts should apply infection control measures similar to those recommended in the hospital setting."
Editor's Note: This study was supported by grants from the Programme Régional de Recherche Clinique, Direction de la Recherche Clinique, AP-HP, Paris (a publicly funded non-profit organization). 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, August 10, 2009
Radiation Therapy May Increase Diabetes Risk in Childhood Cancer Survivors
CHICAGO—Childhood cancer survivors treated with total body or abdominal radiation may have an increased risk of diabetes, according to a report in the August 10/24 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. This correlation does not appear to be related to patients' body mass index or physical inactivity. "As a result of their curative therapies, childhood cancer survivors face an increased risk of morbidity and mortality," with almost 75 percent of survivors developing a chronic health condition and 42.4 percent developing a severe, disabling or life-threatening condition 30 years after diagnosis, according to background information in the article. Cardiovascular disease, in particular, is a significant cause of deaths in this group. "In the general population, diabetes mellitus is strongly associated with an increased risk of cardiovascular disease and all-cause death." Lillian R. Meacham, M.D., of Emory University and AFLAC Cancer Center and Blood Disorders Service, Atlanta, and colleagues compared the prevalence of diabetes in a sample of 8,599 childhood cancer survivors (diagnosed before age 21 between 1970 and 1986) and 2,936 randomly selected siblings of the survivors (average ages 31.5 and 33.4 at follow-up in 2003, respectively). Medication use, treatment exposures (including irradiation, or exposure to radiation treatments) and factors that may have modified the risk of diabetes were noted. Of the survivors, 218 (2.5 percent) reported having diabetes, while 49 (1.7 percent) of siblings reported having the condition. "After adjustment for body mass index, age, sex, race/ethnicity, household income and insurance, the survivors were 1.8 times more likely than the siblings to report diabetes mellitus, with survivors who received total body irradiation, abdominal irradiation and cranial irradiation at increased risk," the authors write. "Survivors who were treated with abdominal irradiation were 2.7 times as likely to report diabetes mellitus as those who were not treated with abdominal irradiation or total body irradiation; those treated with total body irradiation were 7.2 times as likely to report diabetes mellitus." Survivors diagnosed with cancer before age 5 were 2.4 times more likely to report diabetes than those diagnosed in late adolescence (from ages 15 to 20). "As in the general population, older age, black or Hispanic/Latino background, lower household income, physical inactivity and increased BMI were associated with an increased risk of diabetes mellitus," they note.
"It is likely that this additional chronic disease in childhood cancer survivors, who frequently also sustain damage to the heart, kidneys and endocrine system, will lead to further morbidity and premature mortality," the authors conclude. "Therefore, it is imperative that clinicians recognize this risk, screen for diabetes and prediabetes when appropriate and approach survivors with aggressive risk-reducing strategies. Moreover, further research is warranted to understand the pathways by which these two modes of radiation therapy lead to diabetes."
Editor's Note: This work was supported by a grant from the Department of Health and Human Services, by funding to the University of Minnesota from the Children's Cancer Research Fund and by funding to St. Jude Children's Research Hospital from the American Lebanese Syrian Associated Charities (ALSAC). 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, August 10, 2009
Seizures During Pregnancy Associated With Risk of Pre-Term and Small Babies
CHICAGO—Women with epilepsy who have seizures during pregnancy appear more likely to give birth to pre-term, small or low-birth-weight babies than women without epilepsy, according to a report in the August issue of Archives of Neurology, one of the JAMA/Archives journals. An estimated 0.2 percent to 0.7 percent of pregnant women have epilepsy, the most common major neurologic complication in pregnancy, according to background information in the article. "While approximately 40 percent of the 18 million women with epilepsy in the world are of childbearing age, managing maternal epilepsy and monitoring the health of the developing fetus remain some of the most perplexing and engaging issues in the fields of neurology and obstetrics," the authors write. Yi-Hua Chen, Ph.D., of Tai Pei Medical University, Taiwan, and colleagues used data from the Taiwan National Health Insurance Research Data set and analyzed records from 1,016 women with epilepsy who gave birth between 2001 and 2003. Of these, 503 had seizures during pregnancy and 513 did not. A control group of 8,128 women who were the same age and gave birth during the same years but did not have epilepsy or any other chronic disease were selected for comparison. Compared to women without epilepsy, women who had seizures during pregnancy had a 1.36-fold greater risk of having a low-birth-weight baby (weighing less than 2,500 grams), a 1.63-fold increased risk of giving birth pre-term (before 37 weeks) and a 1.37-fold increased risk of having a baby who was small for gestational age (having a birth weight below the 10th percentile for age). In addition, when compared with women who had epilepsy but did not have seizures, the odds of women who had seizures during pregnancy having a baby who was small for gestational age were 1.34 times greater. Some previous studies had reported a link between adverse pregnancy outcomes and mothers' epilepsy, but others found no association, the authors note. "Our study further illuminates these conflicting data to suggest that it is the seizures themselves that seem to contribute greatly to the increased risk of infants being delivered preterm, of low birth weight and small for gestational age. For women who remained seizure-free throughout pregnancy, null or mild risk was identified compared with unaffected women." Several mechanisms might explain the association between seizures and adverse pregnancy outcomes. Trauma caused by a woman's seizures could rupture fetal membranes, increasing risk of infection and early delivery. Tension and acute injury may result from contractions in the uterus that occur during seizures. However, additional research is needed to understand how seizures interfere with fetal development.
"Neonates born pre-term, of low birth weight and small for gestational age may be predisposed to diseases during infancy and later life, highlighting the significance of proper intervention strategies for prevention," the authors write. These could include helping women control seizures for a period of time before pregnancy, assisting them in sleeping better, providing education about the risks of seizures while pregnant and teaching improved strategies for coping with stress.
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.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, August 10, 2009
Study Identifies Risk Factors For Transformation of Eye Growths Into Melanoma
CHICAGO—Eight factors may predict whether a choroidal nevus-a benign, flat, pigmented growth inside the eye and beneath the retina-may develop into melanoma, according to a report in the August issue of Archives of Ophthalmology, one of the JAMA/Archives journals. "There is strong interest for early detection of choroidal melanoma [a malignant growth], and its differentiation from nevus continues to be the major impediment," the authors write as background information in the article. Benign choroidal nevi and small melanomas share many characteristics, including color, location and size. "The challenge is to identify the single small melanoma among the thousands of choroidal nevi. It has been estimated that 6 percent of the white population harbors a choroidal nevus and that one in approximately 8,000 of these nevi transform into melanoma." Carol L. Shields, M.D., and colleagues at Wills Eye Institute, Thomas Jefferson University, Philadelphia, studied the medical records of 2,514 consecutive eyes of patients with choroidal nevi between 1974 and 2006. The tumors had a median (midpoint) diameter of 5 millimeters and a median thickness of 1.5 millimeters at the beginning of the study. Choroidal nevi grew into melanoma in a total of 180 eyes (7 percent) over an average follow-up of 53 months, including 2 percent after one year, 9 percent after five years and 13 percent after ten years. The factors that predicted growth into melanoma included five previously identified factors: tumor thickness greater than 2 millimeters, fluid beneath the retina, symptoms such as decreased vision or flashes and floaters, orange pigment and a tumor edge within 3 millimeters of the optic disc. Two new factors were also identified: hollowness of the growth on ultrasound and the absence of a surrounding halo, or circular band of depigmentation. "Until systemic therapies for metastastic uveal melanoma improve, our focus should be on early detection to minimize metastastic disease," the authors write. "All ophthalmologists should participate in this effort and patients with risk factors can be referred for evaluation at centers familiar with the nuances in the diagnosis and management of early melanoma."
Patients with choroidal nevi that do not display any of the seven features of disease should be monitored twice yearly at first and then followed up yearly if their condition remains stable; those with one or two features should be monitored every four to six months; and those with three or more features should be evaluated at an experienced center for possible treatment, they conclude.
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. |
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