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 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 NEUROLOGY NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, September 12, 2005)
SPECIAL ONLINE PUBLICATION — INTERFERON DOES NOT AFFECT DURATION OF "BLACK HOLE" LESIONS IN MULTIPLE SCLEROSIS
ORAL CONTRACEPTIVES ASSOCIATED WITH REDUCED RISK OF MULTIPLE SCLEROSIS
ARCHIVES OF INTERNAL MEDICINE NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, September 12, 2005)
GENETIC FACTORS INFLUENCE PROPENSITY TO BONE FRACTURES IN ELDERLY
CONSUMPTION OF SOY MAY REDUCE RISK OF FRACTURE IN POSTMENOPAUSAL WOMEN
ARCHIVES OF OPHTHALMOLOGY NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, September 12, 2005)
PREVALENCE OF CATARACT CAUSING VISION PROBLEMS APPEARS HIGH AMONG U.S. HISPANICS
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, September 12, 2005
Media Advisory: To contact Francesca Bagnato, M.D., call Paul Girolami at 301-496-5751.
INTERFERON DOES NOT AFFECT DURATION OF "BLACK HOLE" LESIONS IN MULTIPLE SCLEROSIS
CHICAGO—Although treatment with interferon appears to reduce the formation of new areas of damage in the brains of patients with multiple sclerosis (MS), including lesions that appear as highly contrasted images, called black holes, on magnetic resonance imaging (MRI), treatment does not appear to affect the duration of these damaged regions, according to a new study posted online today by the Archives of Neurology, one of the JAMA/Archives journals. The study will be published in the November print edition of the journal.
Previous studies have shown that treatment with interferon beta-1b, a chemical that has activity on the immune system, reduces the formation of lesions visible to MRI, according to background information in the article. Chronic, persisting black holes reflect areas of irreversible nerve fiber loss and permanent damage. Black holes of shorter duration are believed to reflect the presence of short-term swelling. Shortening the duration of black holes, the authors suggest, may prevent the formation of permanent detrimental lesions, ultimately exerting a neuro-protective effect.
Francesca Bagnato, M.D., of the National Institute of Neurological Disorders and Stroke, Bethesda, Md., and colleagues analyzed MRIs for both the formation and duration of black holes for six patients with relapsing-remitting type MS. Monthly MRIs were obtained for 36 months before the treatment was initiated (natural history phase) and for 36 months during treatment with interferon (therapy phase).
The researchers found that the number of new black holes increased during both the treatment and natural history phases for all patients, but the accumulation of new black holes was substantially lower for patients during the treatment phase. The duration of new black holes arising during the treatment phase was not shorter than the duration of black holes arising during the natural history phase, however.
"The sample size is small, but the length of the longitudinal followup (i.e., 72 months) represents a robust and valid data set for describing the course of MS during both the NHPs [natural history phase] and TPs [therapy phase]," the authors note. "We demonstrate that new BHs [black holes] may significantly accumulate over time even when IFNβ-1b [interferon beta-1b] is administered. However, repeated administration of the drug did significantly decrease the rate of BH formation, thus protecting the brain tissue from accumulating degenerative lesions."
"One can postulate that although IFNβ-1b may reduce the frequency of BHs, after the lesion occurs, the drug is not changing the pathological process," the authors write. They suggest larger studies over longer periods might reduce difficulties in interpretation encountered in this study, allowing a better assessment of whether the analysis used might be useful in establishing the proper role of neuroprotective drugs of the central nervous system in the treatment of patients with MS.
(Arch Neurol. 2005;62:1-5. Available to the media pre-embargo at www.jamamedia.org)
For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, September 12, 2005
Media Advisory: To contact Álvaro Alonso, M.D., Ph.D., call Kevin Myron at 617-432-4752.
ORAL CONTRACEPTIVES ASSOCIATED WITH REDUCED RISK OF MULTIPLE SCLEROSIS
CHICAGO—Over a three-year period, the risk of developing multiple sclerosis (MS) was reduced in women taking oral contraceptives, according to a study in the September issue of the Archives of Neurology, one of the JAMA/Archives journals.
In previous studies, estrogen delayed the onset and eased the course of a MS-like disease in animals, suggesting that oral contraceptives, which contain estrogen, and pregnancy and the postpartum period afterward, both states associated with profound hormonal changes, may alter the clinical course or affect the risk of developing the disease, according to background information in the article.
Álvaro Alonso, M.D., Ph.D., of the Harvard School of Public Health, Boston, and colleagues compared 106 women who had a new diagnosis of MS between January 1, 1993 and December 31, 2000 with 1,001 matched women without MS as controls. Individuals included in the analysis were drawn from a research database that includes medical and pharmacy records for three million Britons.
"The incidence of MS in OC [oral contraceptives] users was 40 percent lower than in nonusers," the authors report. "Women had a higher risk of developing first symptoms of MS in the six months following a pregnancy and a non-significant lower risk during pregnancy, compared with those with no pregnancy. ...This is consistent with studies on the effect of pregnancy in patients with MS and the immunological changes associated with pregnancy."
"Recent OC use and, possibly, current pregnancy are associated with a lower risk of developing MS," the authors conclude. "On the contrary, the postpartum period confers a higher risk of MS onset. Our findings suggest that high levels of exogenous [from outside the body] estrogens from OC use and of endogenous [from the body] estrogens during pregnancy may delay the first clinical attack of MS."
(Arch Neurol. 2005;62:1362-1365. Available to the media pre-embargo at www.jamamedia.org)
Editor's Note: This study was supported by a grant from the National Multiple Sclerosis Society, New York, N.Y. Dr. Alonso was supported by a Fulbright Program fellowship, New York.
For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, September 12, 2005
Media Advisory: To contact Karl Michaëlsson, M.D., Ph.D., e-mail: karl.michaelsson{at}surgsci.uu.se.
GENETIC FACTORS INFLUENCE PROPENSITY TO BONE FRACTURES IN ELDERLY
CHICAGO—The importance of genetic factors in an elderly individual's propensity to bone fractures depends on the individual's age and the type of fracture, according to a study in the September 12 issue of the Archives of Internal Medicine, one of the JAMA/Archives journals.
Bone fractures resulting from osteoporosis have a profound impact on quality of life, with only one third of patients regaining their pre-fracture level of function and a substantial risk of death following fracture, according to background information in the article. The authors suggest that twin studies provide one of the most natural study populations for evaluating genetic risk (the relative contribution of genes versus environment). If heritable factors contribute to fractures, monozygotic twins (who have all the same genes, commonly called identical twins) are more likely to have similar rates of fracture than dizygotic twins (who share about half the same genes, commonly called fraternal twins).
Karl Michaëlsson, M.D., Ph.D., of the Uppsala University Hospital, Uppsala, Sweden, and colleagues used the Swedish Twin Registry, the Swedish Inpatient Registry and telephone interviews to evaluate the genetic liability to fracture of the elderly. From the registry of Swedish twins born between 1,896 and 1,944 (3,724 identical twins, 6,314 fraternal same-sex twins and 5,736 fraternal different-sex twins), the researchers were able to identify 6,021 twins with any fracture, with a higher proportion among women (23 percent) than men (14 percent). More than half the cases (3,599) were classified as osteoporotic fractures. The most important osteoporotic fracture, hip fracture, was recorded for 1,055 twins.
Genetic variation in liability to fracture differed considerably by type of fracture and age, the authors report. Less than 20 percent of the overall age-adjusted fracture variance was explained by genetic variation. Heritability was considerably greater for first hip fracture before the age of 69 years and between 69 and 79 years than for hip fractures after 79 years of age.
"We conclude that the genetic influence on susceptibility to fractures is dependent on type of fracture and age at fracture event," the authors write. "The heritability of osteoporotic fractures is stronger than has been previously estimated, especially for early-occurring osteoporotic fractures. A search for genes and gene-environmental interactions that affect early osteoporotic fracture risk is likely to be fruitful, but fracture-prevention efforts at older ages should be focused on lifestyle habits."
(Arch Intern Med. 2005;165:1825-1830. Available to the media pre-embargo at www.jamamedia.org)
Editor's Note: This study was supported by grants from the Swedish Research Council, Stockholm; the National Institute on Aging, Bethesda, Md.; and Uppsala University Hospital, Uppsala, Sweden.
For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, September 12, 2005
Media Advisory: To contact corresponding author Xioa-Ou Shu, M.D., Ph.D., call Clinton Colmenares at 615-322-4747.
CONSUMPTION OF SOY MAY REDUCE RISK OF FRACTURE IN POSTMENOPAUSAL WOMEN
CHICAGO—Postmenopausal women who consumed high daily levels of soy protein had reduced risk of bone fracture, according to a study in the September 12 issue of the Archives of Internal Medicine, one of the JAMA/Archives journals.
Women experience accelerated bone loss at a rate of three to five percent per year for about five to seven years after menopause, putting them at a high risk for bone fracture, according to background information in the article. The U.S. Food and Drug Administration and new clinical guidelines advise against the use of hormone therapy as a first-line treatment for the prevention of osteoporosis in postmenopausal women and emphasize alternatives including exercise and increasing intake of calcium and vitamin D. Growing evidence suggests a potential role for soy in preventing postmenopausal bone loss.
Xianglan Zhang, M.D., M.P.H., from the Vanderbilt University School of Medicine, Nashville, and colleagues examined the relationship between soy food consumption and bone fractures in 24,403 postmenopausal women. The women were part of the Shanghai Women's Health Study, a study of approximately 75,000 Chinese women aged 40 to 70 years, conducted between March 1997 and May 2000. Participants' usual dietary intake was assessed once at the beginning of the study and then during follow-up, approximately two to three years later. Average age was 60 years.
The researchers found that soy consumption may reduce the risk of fracture in postmenopausal women, especially among those in the early years following menopause. During an average follow-up of four and a half years, 1,770 fractures were reported. The median (middle value) daily intakes of soy protein and soy isoflavones (estrogen-like plant chemicals) were 8.5 grams and 38 micrograms, respectively. Participants were divided into five categories, according to their soy intake, with the lowest intake group consuming less than 4.98 grams of soy per day, and the highest group consuming 13.27 grams or more of soy per day. Those in the highest soy protein intake group had a 37 percent reduced relative risk for fracture compared to the lowest intake group. Women in the highest soy isoflavone group had a 35 percent reduced relative risk for fracture compared to the lowest isoflavone group.
"In this prospective cohort study of postmenopausal women, we found that soy food consumption was associated with a significantly lower risk of fracture, particularly among women in the early years following menopause," the researchers write. "The potential impact of timing on the skeletal effects of soy needs to be further addressed in future studies."
(Arch Intern Med. 2005;165:1890-1895. Available to the media pre-embargo at www.jamamedia.org)
Editor's Note: This study was supported by a research grant from the National Institutes of Health, Bethesda, Md.
For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, September 12, 2005
Media Advisory: To contact corresponding author Sheila K. West, Ph.D., call John Lazarou at 410-502-8902.
PREVALENCE OF CATARACT CAUSING VISION PROBLEMS APPEARS HIGH AMONG U.S. HISPANICS
CHICAGO—Prevalence of cataracts causing significant visual problems appears high among older U.S. Hispanics who also often encounter barriers to access to care, according to a study in the September issue of the Archives of Ophthalmology, one of the JAMA/Archives journals.
Although cataract is the leading cause of visual impairment in the Hispanic community, there has been little research on the prevalence of cataract, cataract surgery or factors that may affect whether Hispanic individuals are able to obtain cataract surgery, according to background information in the article.
Aimee Teo Broman, M.A., of the Johns Hopkins School of Medicine, Baltimore, and colleagues conducted a survey of visual impairment and blindness of Hispanic individuals 40 years or older living in southern Arizona between April 1997 and September 1999. Individuals completed a questionnaire, in either English or Spanish, to determine their history of visual problems and eye care as well as their socio-economic status, medical history and preferred language, country of birth and other questions relating to adapting to U.S. culture. Participants' visual acuity was then assessed.
Of the 4,774 people who participated in the interview and examination, 2.8 percent (135) had visually significant cataract and 5.1 percent (244) had undergone bilateral cataract surgery. The researchers found two factors were important in determining whether individuals received cataract surgery: whether they spoke English and whether they had medical insurance.
"Our data suggest that even after adjusting for high rates of diabetes mellitus, U.S. Hispanic individuals are at a greater risk of having a visually impairing cataract than either African American or white individuals," the authors report. "Cataract is the leading cause of visual impairment in this population and is associated with lower levels of self-reported quality of life; however, a significant percentage of those who likely need cataract removal have never obtained surgery in the population."
"In summary, visually significant cataract appears to be high among U.S. Hispanic individuals of Mexican descent, as evidenced by rate of cataract and rate of surgery," the authors conclude. "Language and financial barriers in this population impede access to surgery. Further work to remove these barriers and provide sight restoration is warranted among Hispanic individuals living in the United States."
(Arch Ophthalmol. 2005;123:1231-1236. Available to the media pre-embargo at www.jamamedia.org)
Editor's Note: This project was supported by a grant from the National Eye Institute, Bethesda, Md. and a Research to Prevent Blindness Challenge grant, New York, N.Y.
For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org.
Go back to the top.
