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February 8, 2010 — Embargoed ContentJAMA 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. ARCHIVES OF INTERNAL MEDICINE NEWS RELEASES
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(Embargoed Until: 3 P.M. (CT), Monday, February 8, 2010)
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(Embargoed Until: 3 P.M. (CT), Monday, February 8, 2010)
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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, February 8, 2010
Usual Care Often Not Consistent With Clinical Guidelines for Low Back Pain
CHICAGO—Clinicians often treat patients with low back pain in a manner that does not appear to match the care endorsed by international clinical guidelines, according to a report in the February 8 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. Low back pain is estimated to be the seventh most common reason for a general practitioner visit in Australia and the fifth most common in the United States, according to background information in the article. An overwhelming body of literature on the management of low back pain—more than 1,200 published trials and systematic reviews—makes practice guidelines an efficient way for clinicians to base their care on the best evidence. A previous review concluded that guidelines in 11 countries around the world provide similar recommendations for assessment and management of low back pain. "Given the proliferation of clinical practice guidelines outlining best practice, it is timely to consider how closely usual care aligns with guideline recommendations," write Christopher M. Williams, M.App.Sc., of The George Institute for International Health, Australia, and colleagues. The authors assessed the care provided for new episodes of low back pain during 3,533 patient visits to general practitioners in Australia between 2001 and 2008. These visits were mapped to key recommendations in treatment guidelines; in addition, data were compared for two three-year periods before and after the release of Australian national guidelines in 2004. "Our findings show that key aspects of the usual care provided to patients do not align with the care recommended in international evidence-based guidelines," the authors write. For example, although guidelines discourage the use of imaging, more than one-quarter of patients were referred for radiology, computed tomography or similar tests. Only 20.5 percent of patients received advice and 17.7 percent received simple pain-relieving medications, both of which are recommended as part of initial care for low back pain. Instead of the safer and equally effective acetaminophen, patients were more often prescribed non-steroidal anti-inflammatory drugs (37.4 percent) and opioids (19.6 percent). In addition, patterns of care did not change significantly following the release of local guidelines, the authors note. "Understanding why general practitioners do not follow key treatment recommendations of guidelines is an important prerequisite to improving this situation," they write. Evidence suggests that the views of both patients and clinicians, and potentially miscommunication between the two, contribute to departures from guideline-based care.
"In the back pain field, there has been extensive activity in the past two decades focusing on the evaluation of new and existing therapies within clinical trials and systematic reviews," the authors conclude. "Arguably, we need a parallel line of research that focuses on how best to encourage provision of evidence-based treatments. Educational outreach with broader societal focus may enhance guideline dissemination and reduce the burden of low back pain."
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, February 8, 2010
Study Examines Course and Treatment of Unexplained Chest Pain
CHICAGO—Fewer than half of individuals who have "nonspecific" chest pain (not explained by a well-known condition) experience relief from symptoms following standard medical care, according to a report in the February 8 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. In addition, one-tenth of those with persistent chest pain undergo potentially unnecessary diagnostic testing. More than half of patients with chest pain are classified as not having an underlying heart condition, according to background information in the article. Some have another well-established medical condition, such as upper respiratory tract infection, but for many no pathophysiologic cause can be found. Such non-specific chest pain "is a frequent phenomenon in primary care," the authors write. "However, knowledge about the course and outcome of this condition is sparse." Julia Anna Glombiewski, Ph.D., of Philipps-University of Marburg, Germany, and colleagues studied 807 patients (average age 57.6 years) with non-specific chest pain who visited 74 German primary care offices in 2005 and 2006. The clinicians recorded their preliminary diagnoses, along with any investigations and treatments related to their patients' chest pain. Patients were contacted by phone six weeks and then six months after the initial consultation. Among the 755 study patients who provided data at the six-month follow-up, 419 (55.5 percent) still had chest pain. In addition, 45 (10.7 percent) of those were categorized as using health care in an inappropriate manner, defined as two or more visits to a cardiologist or three or more cardiac diagnostic evaluations—including angiograms and electrocardiograms—within six months. This compared with 24 (7.1 percent) of 336 patients with remitted chest pain. Only six patients, less than 2 percent, were referred to mental health specialists for ongoing chest pain. "This finding is surprising because psychological factors are known to contribute to the development of chronic pain, and psychological consultations are covered by the health care system in Germany," the authors write. "Patients with psychologically caused non-specific chest pain showed more problematic health care-seeking behavior but were rarely referred to mental health professionals. Patients, general practitioners or both seem to be hesitant to involve psychological interventions."
The findings help explain the high prevalence of chest pain in the general population, the authors conclude. "Future research should investigate the development of effective interventions for non-specific chest pain and their implementation within health care systems."
Editor's Note: This study was funded by a grant from the German Federal Ministry of Education and Research. The funding agency had no involvement in the study. 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, February 8, 2010
Hypertension May Predict Dementia in Older Adults With Certain Cognitive Deficits
CHICAGO—High blood pressure appears to predict the progression to dementia in older adults with impaired executive functions (ability to organize thoughts and make decisions) but not in those with memory dysfunction, according to a report in the February issue of Archives of Neurology, one of the JAMA/Archives journals. "Although midlife hypertension has been confirmed as a risk factor for the development of dementia in late life, there have been conflicting findings about the role of late-life hypertension," the authors write as background information in the article. Individuals with mild cognitive (thinking, learning and memory) impairment—the state between aging-related brain changes and fully developed dementia—may experience deficits in different domains. For instance, some have impairments only in memory function and are more likely to develop Alzheimer's disease, whereas those whose impairment follows a stroke or other vascular (blood vessel-related) event often experience executive dysfunction. "Because hypertension is a major risk factor for vascular brain diseases and vascular cognitive impairment, we postulated that the cognitive domain of dysfunction may be the crucial factor that determines the association between hypertension and cognitive deterioration," the authors write. To test this hypothesis, Shahram Oveisgharan, M.D., of University of Western Ontario, Canada, and Isfahan University of Medical Sciences, Isfahan, Iran, and Vladimir Hachinski, M.D., F.R.C.P.C., D.Sc.(Lond)., also of University of Western Ontario, studied 990 older adults (average age 83) with cognitive impairment but no dementia. Over a five-year follow-up period, dementia developed at approximately the same rate among participants with and without hypertension (59.5 percent of individuals with high blood pressure vs. 64.2 percent of those without). A similar pattern was observed among those with memory dysfunction alone and with both memory and executive dysfunction. However, among patients with executive dysfunction only, presence of hypertension was associated with an increased risk of developing dementia (57.7 percent of those with high blood pressure progressed to dementia, vs. 28 percent of those without). "This study may have profound implications for community dwellers with cognitive impairment, no dementia," the authors write. "Worldwide, neurologic disorders are the most frequent cause of disability-adjusted life years; among these, cerebrovascular disease is the most common risk factor, and dementia is the second most common. There is no preventive or therapeutic intervention to mitigate this public health burden."
"We show herein that the presence of hypertension predicts progression to dementia in a subgroup of about one-third of subjects with cognitive impairment, no dementia," they conclude. "Control of hypertension in this population could decrease by one-half the projected 50-percent five-year rate of progression to dementia."
Editor's Note: This work was supported by a grant from the Alzheimer Association. 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, February 8, 2010
Medication Appears Well Tolerated and May Have Beneficial Effects in Patients With Huntington's Disease
CHICAGO—A medication previously studied in patients with Alzheimer's disease (proposed generic name=latrepirdine) appears well tolerated and may improve thinking, learning and memory skills among individuals with Huntington's disease, according to a report in the February issue of Archives of Neurology, one of the JAMA/Archives journals. "Huntington's disease is a hereditary neurodegenerative disorder that affects movement, behavior and cognition and leads to death within 20 years of disease onset," the authors write as background information in the article. "Cognitive [thinking, learning and memory] impairment occurs early in the disease and deteriorates as Huntington's disease progresses, contributing to loss of ability to work and perform activities of daily living." The only approved therapy for Huntington's disease, tetrabenazine, treats only motor symptoms and does not alter the course of the disease or prevent cognitive decline. Abnormalities in mitochondria, parts of cells that help convert food into energy, have been implicated in the development of Huntington's disease. The synthetic molecular latrepirdine stabilizes and improves mitochondrial function, and has been studied as a way to improve cognitive, behavioral and functional outcomes in patients with Alzheimer's disease. Karl Kieburtz, M.D., M.P.H., of the School of Medicine and Dentistry, University of Rochester, N.Y., and colleagues assessed the safety and tolerability of latrepirdine among 91 participants with mild to moderate Huntington's disease at enrollment (2007 to 2008). For 90 days, 46 patients were randomly assigned to take 20 milligrams of latrepirdine three times daily and the other 45 took a matching placebo. The medication was well tolerated (87 percent of the patients given latrepirdine completed the study, compared with 82 percent in the control group) and adverse event rates were similar between the two groups (70 percent in the treatment group vs. 80 percent in the placebo group). In addition, the treatment resulting in improved average scores on an evaluation measuring overall cognitive function. Scores of individuals in the placebo group remained steady over the study period.
"Taken together, our data suggest that latrepirdine, at a dosage of 20 milligrams three times daily, is well tolerated for 90 days in patients with Huntington's disease and may have a beneficial effect on cognition," the authors conclude. "Future studies of latrepirdine are planned to further evaluate the effect of latrepirdine on the cognitive and behavioral symptoms of Huntington's disease."
Editor's Note: This study was funded by a grant from Medivation Inc. to the University of Rochester and in turn through subcontracts to the participating research sites. 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, February 8, 2010
Glaucoma Medications May Be Associated With Reduced Risk of Death Over Four-Year Period
CHICAGO—Glaucoma patients who take medication for the condition appear to have a reduced likelihood of death, according to a report in the February issue of Archives of Ophthalmology, one of the JAMA/Archives journals. Glaucoma (a common condition that consists of elevated pressure in the eye, and that can lead to loss of vision) usually affects older adults, who are at risk for co-existing medical conditions that can negatively affect their survival, according to background information in the article. "In recent years, numerous studies have assessed whether glaucoma is associated with mortality," the authors write. "Few studies, however, have considered whether the medications commonly used to treat glaucoma may affect the association between glaucoma and death." Joshua D. Stein, M.D., M.S., and colleagues at the University of Michigan, Ann Arbor, conducted a study evaluating the relationship between glaucoma medication use and death in 21,506 individuals age 40 or older (average age 60) with glaucoma or suspected glaucoma from January 2003 to December 2007 who were enrolled in a large managed care network. Glaucoma medication use was defined as filling one or more prescriptions for a 30-day or more supply of the drug during the study period. Deaths were reported by family members, employers or health care professionals and other demographic information was noted at the beginning of the study. More than half of the patients had suspected glaucoma, the others had one or more types of glaucoma. "During the study period, 6,049 beneficiaries (28.1 percent) filled one or more prescriptions for a glaucoma medication; 2,021 individuals (9.4 percent) underwent glaucoma surgery," the authors write. Of the 21,506 patients, 237 (1.1 percent) died during the study. When compared to those with no glaucoma medication use, those using any class of glaucoma medication had a 74 percent reduced risk of death. "This association was observed for use of a single agent alone, such as a topical beta-antagonist or a prostaglandin analogue, and for use of different combinations of drug classes," the authors write.
"Additional studies are needed to determine whether this result is best explained by a protective effect of the medications themselves or by other confounding factors, such as access to care or providers' prescribing patterns," the authors conclude. "Future investigations should explore this association further because these findings may have important clinical implications."
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, December 14, 2009
Mountaineers Develop Corneal Swelling During High-Altitude Climbs, But Vision Does Not Appear Affected
CHICAGO—Swelling commonly occurs in the corneas of mountain climbers, but does not appear to affect vision at altitudes of up to 6,300 meters (about 20,670 feet), according to a report in the February issue of Archives of Ophthalmology, one of the JAMA/Archives journals. "High-altitude mountaineering is a popular recreational sport among healthy lowlanders," the authors write as background information in the article. "As a consequence of the exposure to hypobaric atmospheric conditions with a consecutive decrease in oxygen saturation, high-altitude climbing may lead to acute mountain sickness and the rare but potentially fatal high-altitude cerebral edema." Changes to the cornea, the transparent membrane covering the front of the eye, also occur during high-altitude climbs and may cause potentially hazardous vision loss. Martina Monika Bosch, M.D., of University Hospital Zurich, Switzerland, and colleagues studied the effects of high-altitude climbing on corneal thickness among 28 healthy volunteers climbing Mount Muztagh Ata in western China. The mountaineers were randomly assigned to two different ascending paths, with one group being allotted a shorter time to acclimate before ascending to 6,265 meters. Corneal thickness, visual acuity and blood oxygen levels were measured in climbers before, during and after their ascent, and symptoms of acute mountain sickness were also assessed. In groups with both patterns of ascent, corneal thickness increased with increasing altitude and decreased after descent, and the amount of decrease in blood oxygen levels paralleled this increase. The group with the shorter acclimatization time experienced a greater increase in corneal thickness. However, no significant decrease in visual acuity was observed in either group. When controlling for age and oxygen saturation, there was a correlation between symptoms of mountain sickness and corneal thickness. This was possibly due to these individuals' higher overall susceptibility to inadequate oxygen supplies. The exact cause of corneal swelling during ascent remains controversial, the authors note. The current findings suggest that the body's delivery of oxygen to the aqueous humor—the fluid inside the eyeball, between the cornea and iris—may be more important in corneal oxygen levels than previously thought.
"It seems that visual acuity in healthy corneas is not adversely affected despite the presence of edema at altitudes up to 6,300 meters," the authors conclude. However, it is likely that ascents to more extreme altitudes—above 8,000 meters or about 26,000 feet—may induce greater damage to the cornea and lead to dangerous visual loss.
Editor's Note: This project was supported by a research grant from the Swiss National Research Science Foundation, a research grant by the Swiss Society of Mountain Medicine, a private grant to the Department of Ophthalmology, University Hospital Zurich and by an unconditional grant from Pfizer, Switzerland. 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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