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 INTERNAL MEDICINE NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, November 13, 2006)
HIGHER RED MEAT INTAKE MAY INCREASE RISK FOR CERTAIN BREAST CANCERS
FLU VACCINE ASSOCIATED WITH SLIGHT INCREASE IN RISK OF HOSPITALIZATION FOR NEUROLOGICAL DISORDER
STUDIES EXAMINE COLORECTAL CANCER SCREENING RATES
ARCHIVES OF NEUROLOGY NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, November 13, 2006)
SPECIAL ONLINE PUBLICATION — YOUNGER STROKE SURVIVORS HAVE LESS ACCESS TO MEDICAL CARE, MEDICATIONS
HIGHER LEVEL OF CERTAIN FATTY ACID ASSOCIATED WITH LOWER DEMENTIA RISK
ARCHIVES OF OPHTHALMOLOGY NEWS RELEASES
(Embargoed Until: 3 P.M. (CT), Monday, November 13, 2006)
EYE TESTS MAY PREDICT FUTURE VISION PROBLEMS IN PRETERM CHILDREN
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
Save the Date: JAMA will present new research from its theme issue on men's health at a media briefing on Tuesday, November 14, at the Millennium Broadway Hotel in New York. Program and registration information will be provided in a future email.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, November 13, 2006
Media Advisory: To contact Eunyoung Cho, Sc.D., call Lori J. Shanks at 617-534-1604.
HIGHER RED MEAT INTAKE MAY INCREASE RISK FOR CERTAIN BREAST CANCERS
CHICAGO—Eating more red meat may be associated with a higher risk for hormone receptor–positive breast cancers in premenopausal women, according to a report in the November 13 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
“Breast tumors are often characterized by hormone (estrogen and progesterone) receptor status,” the authors write as background information in the article, meaning that the cancer is classified by whether these hormones can bind to proteins on the surface of the tumor. “Although the incidence rates of hormone receptor–negative tumors have remained relatively constant, the incidence of hormone receptor–positive tumors has been increasing in the United States, especially among middle-aged women.” The diets of American women may be linked to this increase, since some foods—including certain components of red meat—can contain hormones or hormone-like compounds that influence tumors through their hormone receptors.
Eunyoung Cho, Sc.D., Brigham and Women’s Hospital and Harvard Medical School, Boston, and colleagues studied the association between red meat consumption and breast cancer in 90,659 women who were part of the Nurses’ Health Study II, a large ongoing study of nurses who responded to an initial questionnaire in 1989. Dr. Cho and colleagues followed the women from 1991 (when they had an average age of 36) through 2003. The participants filled out food questionnaires in 1991, 1995 and 1999, on which they recorded how often they regularly consumed more than 130 different foods and beverages. Every two years, they reported whether or not they had developed breast cancer; reported cases were confirmed through hospital records and pathology reports. Only women who were premenopausal and had not previously had cancer were included in this analysis, and those who went through natural menopause or had their ovaries removed during the 12 years of the study were excluded after that date.
By the end of the study, 1,021 women had developed breast cancer, including 512 cases that were estrogen and progesterone receptor positive, 167 that were estrogen and progesterone receptor negative, 110 with mixed status and 232 with unknown status. The highest intake of red meat was not significantly associated with the risk for breast cancer overall or for hormone receptor–negative cancers, but was associated with an increased risk for hormone receptor–positive cancer. Women who ate more than one and one-half servings of red meat per day had almost double the risk of hormone receptor–positive breast cancer compared with those who ate three or fewer servings per week. The associations remained similar when the researchers calculated red meat intake in grams instead of servings, and also when they split the women into five groups based on how much red meat they ate.
“Several biological mechanisms may explain the positive association between red meat intake and hormone receptor–positive breast cancer risk,” the authors write. Known cancer-causing compounds in cooked or processed red meat increase mammary tumors in animals and have been suspected of causing breast cancer in humans. In addition, cattle in the United States are treated with hormones to promote growth, which could also influence breast cancer risk. The type of iron available in red meat also may enhance tumor formation.
“Given that most of the risk factors for breast cancer are not easily modifiable, these findings have potential public health implications in preventing breast cancer and should be evaluated further,” the authors conclude.
(Arch Intern Med. 2006;166:2253-2259. 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. 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.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, November 13, 2006
Media Advisory: To contact corresponding author Kumanan Wilson, M.D., M.Sc., call Julie Dowdie at 416-480-4780.
FLU VACCINE ASSOCIATED WITH SLIGHT INCREASE IN RISK OF HOSPITALIZATION FOR NEUROLOGICAL DISORDER
CHICAGO—Influenza vaccine is associated with a small but increased risk for hospitalization with the potentially debilitating neurological disorder known as Guillain-Barré syndrome, although the absolute risk associated with the vaccine is very low, according to a report in the November 13 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Guillain-Barré syndrome affects about one in 100,000 individuals per year, according to background information in the article. The disorder occurs when the body’s immune system attacks part of the nervous system, causing weakness or tingling that can eventually worsen to paralysis. Previous reports have linked influenza vaccine to the development of Guillain-Barré syndrome, but uncertainty remains about the association.
David N. Juurlink, M.D., Ph.D., Institute for Clinical Evaluative Sciences (ICES), University of Toronto, Ontario, and colleagues studied residents of Ontario, Canada, where a universal influenza immunization program that provides free yearly vaccinations to all residents age 6 months or older was instituted in October 2000. First, the researchers identified all the cases of hospitalization for Guillain-Barré syndrome among Ontario residents age 18 and older between April 1, 1993, and March 31, 2004. They then identified which of those patients had received flu vaccines and compared their risk for hospitalization for Guillain-Barré syndrome within two to seven weeks after vaccination to the time period 20 to 43 weeks later. In a second analysis examining the total number of hospitalizations for Guillain-Barré syndrome in Ontario between 1991 and 2004, the investigators compared the numbers of cases before and after the immunization program began in 2000.
Between 1993 and 2004, the researchers identified 1,601 hospital admissions due to Guillain-Barré syndrome in Ontario, 269 of which occurred within 43 weeks of the patient receiving a vaccine in October or November (which was assumed to be an influenza vaccine). Patients were about one and a half times as likely to be hospitalized for Guillain-Barré syndrome in the two to seven weeks after vaccination than they were 20 to 43 weeks later. In the second analysis, the researchers looked at the 2,173 hospital admissions due to Guillain-Barré syndrome that occurred in Ontario between 1991 and 2004 (170 new cases per year, or about 14 cases per million persons per year). They did not find any significant difference in the rate of hospitalization for Guillain-Barré syndrome before and after the inception of the immunization program.
“Our results must be interpreted carefully,” the authors write. “The increase in relative risk we observed corresponds to a very low absolute risk for Guillain-Barré syndrome, given the low baseline incidence of the disease (approximately one in 100,000 population). Furthermore, the lack of association on a population health level is consistent with the prevalent impression that influenza vaccine is only one of many potential causes of Guillain-Barré syndrome.”
Because of the low overall risk for Guillain-Barré syndrome, physicians and patients should primarily consider the benefits of flu vaccines when making a decision about whether or not to get immunized. However, individuals who receive the shots should be told about the risk for Guillain-Barré syndrome and a surveillance strategy should be implemented as part of any mass vaccination program.
(Arch Intern Med. 2006;166:2217-2221. Available to the media pre-embargo at www.jamamedia.org).
Editor's Note: This study was sponsored in part by a grant from the Canadian Institutes of Health Research. Co-authors Drs. Juurlink and Wilson are supported by New Investigator Awards from the Canadian Institutes of Health Research. Dr. Juurlink is sponsored by the University of Toronto Drug Safety Research Group. Co-author Dr. Kwong is supported by a fellowship award from the Canadian Institutes of Health Research. 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.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, November 13, 2006
Media Advisory: To contact Hashem B. El-Serag, M.D., M.P.H., call Kimberlee K. Barbour at 713-798-7971. To contact Shahnaz Sultan, M.D., call April Frawley Birdwell at 352-273-5817. To contact editorialist Hemant K. Roy, M.D., call Jennifer Mitchell at 847-570-6132.
STUDIES EXAMINE COLORECTAL CANCER SCREENING RATES
CHICAGO—The rate of colorectal cancer screening appears to be increasing among Veterans Affairs patients, although use of colonoscopy is less common than other screening procedures, according to a report in the November 13 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. A second report in the same journal shows that younger veterans with other illnesses and reduced life expectancies may not necessarily benefit from such screening and may even be harmed, but continue to be screened at high rates.
About 145,290 U.S. individuals developed colorectal cancer in 2005 and 56,290 died from the disease, according to background information in the first article. Screening for the disease has been shown to decrease illness and death. Methods include fecal occult blood testing (FOBT), which monitors for hidden blood in the stools, and colonoscopy, in which the large intestine (colon) is examined using a long flexible instrument known as a colonoscope. “Because it is the most invasive and costly approach and because it is usually performed by specialists, until recently, colonoscopy was primarily used to screen high-risk individuals, for diagnostic purposes or to follow up on abnormal results of other screening tests,” the authors write. However, because it can examine the whole colon and remove potentially cancerous growths at the same session, colonoscopy is increasingly common as indicated by data from Medicare and other health care systems and is recommended as the most accurate screening tool by a growing number of professional organizations.
Hashem B. El-Serag, M.D., M.P.H., of the Michael E. DeBakey VA Medical Center and Baylor College of Medicine, Houston, and colleagues studied screening patterns in patients who received care in the Department of Veterans Affairs between 1998 and 2003. By searching national inpatient and outpatient VA databases, the researchers identified all patients age 49 to 75 who had undergone FOBT, colonoscopy, a test known as flexible sigmoidoscopy, or double contrast barium enema, another screening method that involves taking X-rays of the colon and rectum.
A total of 5,125,938 screening tests for colorectal cancer were performed on 2,402,657 patients between 1998 and 2003—an average of 2.1 procedures per patient. The number of tests increased from 432,778 in 1998 to 1,179,764 in 2003. Also in that time period, the proportion of FOBT tests increased from 81.7 percent to 90.4 percent; screening colonoscopy declined from 5.7 percent to 4.7 percent; flexible sigmoidoscopy declined from 8.3 percent to 3.6 percent; and double contrast barium enema declined from 4.1 percent to 1.3 percent.
Although the number of screening colonoscopies performed during that time increased from 24,955 to 55,199, the percentage of colonoscopies used for screening rather than diagnostic or other purposes increased only slightly, from 34.3 percent to 38.4 percent. “Although screening colonoscopy more than doubled in frequency, it still constitutes a small proportion of colorectal cancer screening,” the authors write. “Overall, there was no significant difference in the likelihood of undergoing screening colonoscopy between 1998 and 2003.”
FOBT has been criticized for its lack of ability to correctly identify those with and without colorectal cancer, they continue. “Apart from the advantages of colonoscopy … the effectiveness of an FOBT-based screening program in clinical settings (as opposed to clinical trials) is unclear. The predominant use of FOBT for colorectal cancer screening in the VA, while strikingly different from other health care systems in the United States, may not necessarily lead to worse outcomes in terms of colorectal cancer–related incidence and mortality. It does, however, call for closer examination of the process and outcomes of this practice in VA settings.”
In the second study, Shahnaz Sultan, M.D., then at Duke University Medical Center and Durham Veterans Affairs Medical Center, North Carolina, and now at University of Florida College of Medicine, Gainesville, and colleagues examined the relationship between colorectal cancer screening, health status and other illnesses in 861 patients treated at a single VA Medical Center between 1996 and 2004. The participants were age 50 to 64 with no history of colorectal cancer or screening. Each patient completed two surveys about their health and comorbid (co-occurring) illnesses; data about screening were collected from hospital and individual medical records.
Within five years of their initial clinic visit, 395 (45.9 percent) of the veterans underwent screening for colorectal cancer, including 258 (65.3 percent) who had FOBT and 138 (34.9) who had a colonoscopy. Researchers separated patients into groups by age and health status, with three groups for age (50 to 54, 55 to 59, and 60 to 64), three for comorbid diseases (no or mild, moderate, or severe) and four for health status (with one being the worst and four being the best). High screening rates were observed for patients with poor health scores and co-occurring illnesses. This included 84 of 187 (44.9 percent) of those with moderate illness and 55 of 120 (45.8 percent) of those with severe illness, as well as 88 of 216 (40.7 percent) of those with the worst health scores.
For a screening test to be beneficial, it must reduce the rates of patients who die from the disease they are screened for and prolong the life expectancy of those who are screened, the authors write. “In the context of colorectal cancer screening, if an individual’s life expectancy is anticipated to be fewer than five years, then screening may be of little benefit,” they continue. “In our study, 52 patients died during the five-year follow-up period from non–colorectal cancer deaths, and of these patients, 71.2 percent had undergone colorectal cancer screening but had not derived any survival benefit. Most of these individuals had limited life expectancy based on their health status and comorbidity score and may, therefore, have been inappropriately screened.”
“Future research should focus on the development of appropriate decision tools to reduce potentially inappropriate colorectal cancer screening in severely chronically ill patients,” the authors conclude.
(Arch Intern Med. 2006;166:2202-2208 and 2209-2214. Available to the media pre-embargo at www.jamamedia.org).
Editor's Note: Please see the articles for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
EDITORIAL: LIMITED RESOURCES STRAIN SCREENING PROGRAMS
Although screening for colorectal cancer has been shown to reduce death and the occurrence of the disease, screening rates still lag behind those for breast and prostate cancer patients, write Hemant K. Roy, M.D., Evanston-Northwestern Healthcare, Illinois, and colleagues in an accompanying editorial.
Medicare coverage and high-profile endorsements have increased interest in colonoscopies, the most accurate screening method, they write. “The increased success of these public awareness campaigns has raised an important issue—the insufficient health care resources to meet the needs. For instance, if colonoscopies were actually performed on the entire population of more than 70 million Americans older than 50 years, the annual costs would exceed $10 billion. Moreover, many estimates suggest that entire population screening would exceed existing endoscopic capacity.”
Targeting high-risk patients for colonoscopies and effectively using other screening methods for the rest of the population, as well as working to develop additional tests that could separate patients by risk level, will help physicians efficiently use the screening resources available, they conclude.
(Arch Intern Med. 2006;166:2177-2179. Available to the media pre-embargo at www.jamamedia.org).
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.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, November 13, 2006
Media Advisory: To contact Deborah A. Levine, M.D., M.P.H., call Kristen Ruggeri at 205-934-8935.
YOUNGER STROKE SURVIVORS HAVE LESS ACCESS TO MEDICAL CARE, MEDICATIONS
CHICAGO—Stroke survivors less than 65 years old report having more difficulty accessing physicians and affording medications than stroke survivors older than 65, according to an article posted online today that will appear in the January 2007 print issue of Archives of Neurology, one of the JAMA/Archives journals.
Approximately 5.4 million U.S. adults have survived a stroke, according to background information in the article. These individuals require comprehensive care to modify their risk factors for heart disease and prevent secondary strokes; the risk for recurrent strokes ranges from 5 percent to 15 percent each year. Additional strokes and other cardiovascular events, such as heart attack, in stroke survivors increase their rates of illness and death as well as their health care costs. Stroke survivors younger than age 65 may typically do not qualify for Medicare health insurance and are more likely to be uninsured than older stroke survivors.
Deborah A. Levine, M.D., M.P.H. Birmingham Veterans Affairs Medical Center and University of Alabama at Birmingham, and colleagues assessed access to care among stroke survivors age 45 years and older who responded between 1998 and 2002 to the National Health Interview Survey, an annual government-conducted survey. Respondents answered questions about whether they had ever been diagnosed with stroke, if they had seen or talked to a general physician or specialist in the past 12 months, and whether they needed prescription medications in the past year but could not afford them.
Of the 3,681 total stroke survivors interviewed, 2,509 were age 65 and older (average age 76) and 1,172 were age 45 to 64 (average age 56). Compared with older stroke survivors, younger stroke survivors were more likely to be black (19 percent vs. 10 percent), male (52 percent vs. 47 percent) and to not have health insurance (11 percent vs. .4 percent). They also were more likely to report not visiting a general physician (14 percent vs. 10 percent), not visiting a general physician or medical specialist (8 percent vs. 5 percent) and the inability to afford medications (15 percent vs. 6 percent). “Lack of health insurance explained some of the reduced access to physician care among younger stroke survivors but not their more frequent problems with medication affordability,” the authors write.
Because treatments to prevent second strokes often include drugs to reduce blood pressure and cholesterol and are usually administered by a primary care physician, younger stroke survivors may be at higher risk for recurrence. “Further research is needed to determine whether this younger high-risk population has adverse outcomes, such as death and cardiovascular events, or has increased long-term health care utilization due to reduced access to physician care and medications,” the authors conclude. “Further work addressing access gaps, linking to related health outcomes and costs and demonstrating the effectiveness and cost-effectiveness of possible improvement strategies is warranted.”
(Arch Neurol. 2007;64:(doi:10.1001/archneur.64.1.noc60002). Available to the media pre-embargo at www.jamamedia.org).
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.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, November 13, 2006
Media Advisory: To contact Ernst J. Schaefer, M.D., call Siobhan Gallagher at 617-636-6586. To contact editorialist Martha Clare Morris, Sc.D., call Mary Ann Schulz at 312-942-7816.
HIGHER LEVEL OF CERTAIN FATTY ACID ASSOCIATED WITH LOWER DEMENTIA RISK
CHICAGO—Individuals who have higher levels of a fatty acid known as docosahexaenoic acid (DHA) in their blood may have a significantly lower risk of developing dementia and Alzheimer’s disease, according to a report in the November issue of Archives of Neurology, one of the JAMA/Archives journals.
Age, family history and genetic factors have all been found to increase the risk of dementia and Alzheimer’s disease, a neurodegenerative disorder that causes 70 percent of cases of dementia in the elderly, according to background information in the article. Recent studies have found that high levels of homocysteine, an amino acid that is derived from proteins in the diet and that can accumulate in the blood and contribute to heart disease, increase the risk for Alzheimer’s disease and dementia. In addition, DHA, an omega-3 polyunsaturated fatty acid found in fish, appears to affect dementia risk and to be important for the proper functioning of the central nervous system.
Ernst J. Schaefer, M.D., Jean Mayer U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, and colleagues studied the association between DHA levels and dementia in the blood of 899 men and women who were part of the population-based Framingham Heart Study. The participants of an average age of 76 years provided blood samples and underwent neuropsychological testing, and were followed for an average of nine years. A subgroup of 488 also filled out a questionnaire assessing their diet, including information about fish consumption. None of the participants had dementia at the beginning of the study; and they were given a mental examination every two years to screen for its development.
Through the nine-year study period, 99 out of 899 participants developed dementia, including 71 with Alzheimer’s disease. After controlling for other known risk factors for dementia, including age and homocysteine levels, and dividing the study population into fourths (quartiles) based on levels of DHA, the researchers found that men and women in the quartile with the highest DHA levels had a 47 percent lower risk of developing dementia and 39 percent lower risk of developing Alzheimer’s disease than the other three quartiles with lower DHA levels. Among the participants who completed the dietary questionnaire, those in the top quartile of blood DHA levels reported that they ate an average of .18 grams of DHA a day and an average of three fish servings a week. Participants in the other quartiles ate substantially less fish.
DHA levels in the blood vary by the degree to which the liver converts alpha-linolenic acid, an essential fatty acid, to DHA and also by the amount of DHA in the diet. “In our study, the correlation between [blood] DHA content and fish intake was significant, indicating that fish intake is an important source of dietary DHA,” the authors write.
“In the future, it will also be important to determine whether combined dietary supplementation with DHA can decrease further mental deterioration in patients with established dementia,” they conclude.
(Arch Neurol. 2006;63:1545-1550. Available to the media pre-embargo at www.jamamedia.org).
Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
EDITORIAL: LINK BETWEEN FATTY ACIDS AND DEMENTIA MAKES BIOLOGICAL SENSE
There is a strong basis in biology for the neuroprotective effects of DHA, writes Martha Clare Morris, Sc.D., Rush University Medical Center, Chicago, in an accompanying editorial.
Lipids, a collective term for fats and oils, make up about 50 to 60 percent of the brain’s dry weight, and DHA is the most abundant fatty acid found in the cell membranes of the brain’s gray matter, she writes. Studies done in the 1980s and 1990s found that DHA is important to a variety of brain cell components and functions. “Indeed, the level of DHA in the brain has been shown to be very important for learning ability and memory in early life in studies of rodents, baboons and humans,” Dr. Morris writes. “It is only recently that the omega-3 fatty acids have been investigated for their importance to the aging brain. The DHA composition of the brain decreases with age as a result of increased oxidative [result of oxygen exposure] damage to the lipid membranes.”
Research indicates that consuming more DHA in the diet later in life increases DHA levels in the aging brain. However, more studies are needed to determine whether omega-3 supplements could prevent dementia, she concludes.
(Arch Neurol. 2006;63:1527-1528. Available to the media pre-embargo at www.jamamedia.org).
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.
Go back to the top.
EMBARGOED FOR RELEASE UNTIL 3 P.M. (CT), MONDAY, November 13, 2006
Media Advisory: To contact Eva K. Larsson, M.D., Ph.D., e-mail: eva.larsson{at}ogon.uu.se.
EYE TESTS MAY PREDICT FUTURE VISION PROBLEMS IN PRETERM CHILDREN
CHICAGO—Testing the eyes of preterm children when they reach 2.5 years of age may predict vision problems at age 10, according to a report in the November issue of Archives of Ophthalmology, one of the JAMA/Archives journals.
“Ophthalmological studies of preterm (prematurely born) children have resulted in recommendations that they need follow-up examinations, to find those in need of extra help,” the authors provide as background information in the article. “However, such follow-up programs are expensive and must be based on accurate knowledge of the prevalences of ophthalmological disorders in preterm and full-term children.” Previous studies have found that refractive errors, or errors in the degree of light that reaches the back of the eye, are more common in preterm children (born before 35 weeks gestation) than full-term children.
Eva K. Larsson, M.D., Ph.D., and colleagues at Uppsala University Hospital, Sweden, performed retinoscopies—tests for refractive errors that involve examining the back of the eye—in 198 preterm children at 6 months, 2.5 years and 10 years of age. The investigators assessed the development of astigmatism, an unequal curve in one of the eye’s refractive surfaces, and anisometropia, a difference in refractive power between the two eyes that can lead to partial vision loss.
The prevalence and degree of astigmatism declined between 6 months and 2.5 years and then remained stable through 10 years; 108 children had astigmatism at six months, 54 at 2.5 years and 41 at 10 years. The amount of anisometropia in the entire group showed no change between 6 months and 2.5 years of age but increased between 2.5 and 10 years. The prevalence, however, remained stable: 15 children had anisometropia at 6 months, 17 at age 2.5 and 16 at age 10. “The presence of astigmatism and anisometropia at 2.5 years of age were the strongest risk factors for having astigmatism and anisometropia at 10 years of age,” the authors write.
“In this population-based study, we found that a refractive error at 2.5 years of age predicts that refractive error will also be present at 10 years of age,” they conclude. “Recommendations for follow-up examinations must include all aspects of visual function, i.e., visual acuity, contrast sensitivity and visual fields, as well as the refraction, strabismus and perceptual problems. All preterm children should be included in such follow-up examinations for refractive error, irrespective of the retinopathy of prematurity stage,” or the degree to which blood vessels in the retina have developed abnormally because of preterm birth.
(Arch Ophthalmol. 2006;124:1608-1614. Available to the media pre-embargo at www.jamamedia.org).
Editor's Note: This study was supported by Stiftelsen Synfrämjandets Foundation for Research and the Crown Princess Margaretha Foundation for 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.
Go back to the top.
