Deep vein thrombosis (DVT) occurs when a blood clot forms within a deep vein, most often in the calf or thigh area.
The American Academy of Orthopaedic Surgeons offers this list of risk factors that may increase the likelihood of DVT:
Having had a pulmonary embolism or a previous case of deep vein thrombosis.
Having had cancer that has spread.
Having had another vein condition, such as varicose veins.
Being a smoker.
Taking estrogen.
Being pregnant.
Being obese.
An abnormality in two genes can make a common class of chemotherapy drugs used to fight breast cancer less effective, U.S. researchers said on Sunday in a finding that could help doctors better tailor treatments.
They said changes in two genes on a small region of chromosome 8q made tumors resist the effects of drugs called anthracyclines, but not other types of chemotherapy drugs.
“This is useful because it helps select who might be resistant to anthracyclines,” said Dr. Andrea Richardson of the Dana-Farber Cancer Institute in Boston, whose study appears in the journal Nature Medicine.
“This can potentially be used to help guide therapy on a more personalized way based on a patient’s own tumor. That’s why it’s exciting,” Richardson said in a telephone interview.
She said it may be possible to develop a genetic test to better tailor treatments to a patient’s individual tumor.
Doctors already can test for certain genes to tell whether a woman’s breast cancer is sensitive to estrogen, making her a candidate for hormone-blocking drugs such as tamoxifen.
Breast cancer patients whose tumors generate a protein called HER-2, which can fuel cancer growth, are often treated with Herceptin, or trastuzumab, a drug developed by Genentech, now a unit of Roche Holding AG.
Last month, a study presented at the American Association for Cancer Research San Antonio Breast Cancer Symposium found that a gene-based test called Oncotype DX made by Genomic Health Inc helped identify women who are not likely to benefit at all from chemotherapy.
WHICH DRUG WORKS BEST
But Richardson said there were no tests to help doctors sort out which chemotherapy drug is best to use after surgery.
“In breast cancer, most patients get two or three types of chemotherapy and every patient gets basically the same thing. Those drugs have their own toxicities. It would be great if we could not give something that is going to be toxic and not effective,” she said.
For the study, Richardson, colleague Zhigang Charles Wang and others studied the DNA of breast tumor samples taken from 85 patients before they had any chemotherapy.
In tumors that turned out to be drug-resistant, the team found a region on chromosome 8 that had many extra or amplified copies of DNA stretches.
When two genes in this region called LAPTM4B and YWHAZ were overexpressed — working too hard — the tumors were resistant to anthracycline drugs.
Tests on cells in the lab confirmed that.
Using data from a Belgian study in which breast cancer patients were first treated with chemotherapy drugs including anthracyclines before their tumors were removed, the team accurately predicted that patients who had the abnormal gene signature would fare poorly with anthracycline drugs.
“We were able to test in a blinded way. The expression level of those genes predicted who would be resistant to the anthracycline. That validated the finding in a very direct way,” Richardson said.
Richardson said the team was now testing three different approaches to developing a genetic test for this problem.
“Hopefully, we’ll be able to develop an assay within the next year or so. We’d need to test it in a larger number of patients to confirm that our findings hold up,” she said.
(Editing by Vicki Allen)
Reuters Health
People who have an unrealistically high opinion of themselves have less activity in the frontal lobes of their brain, researchers have found.
“In healthy people, the more you activate a portion of your frontal lobes, the more accurate your view of yourself is. And the more you view yourself as desirable or better than your peers, the less you use those lobes,” Jennifer Beer, an assistant professor of psychology at the University of Texas at Austin, said in a university news release.
In the new study, 20 volunteers had MRI brain scans while they answered questions about how they compared to their peers on positive traits, such as likeability, modesty and maturity, and on negative traits, such as unreliability, materialism, messiness and narrow-mindedness.
The participants who had a very positive self-image had less activity in the orbitofrontal cortex, a region of the frontal lobe generally associated with reasoning, planning, decision-making and problem-solving. Some of the volunteers with a realistic self-view had four times more frontal lobe activation than the participant with the highest self-regard, the researchers found.
The study is published in the February issue of the journal NeuroImage.
Beer said the findings may help improve understanding of brain function in seniors or people who suffer from depression or other mental illnesses. It may also prove important in the treatment of recovering methamphetamine addicts whose frontal lobes are often damaged by drug use and who can overestimate their ability to remain drug-free.
SOURCE: University of Texas at Austin
Aviation and medicine both require professionals to hold peoples’ lives in their hands. Now, study findings hint that hospitals may improve patient safety by drawing on aviation-type safety initiatives.
When medicine “turns its eyes to the sky,” patient safety on the ground may improve, Dr. Harry C. Sax, at Brown University in Providence, Rhode Island, noted in a telephone interview with Reuters Health.
Pre-flight checklists and non-punitive incident reporting are measures that significantly minimize aviation accidents, Sax and colleagues point out in the Archives of Surgery.
In their study, they assessed how hospital staff at a 722-bed university hospital and a 247-bed community hospital implemented and felt about similar safety initiatives.
The hospitals trained a total of 857 hospital staff with the “Lessons from the Cockpit” training course as one of their safety initiatives. The course highlights team safety-enhancing efforts used in aviation and how similar efforts may have benefit in other industries.
Immediate post-training surveys revealed that staff were more willing to commit themselves to team efforts to improve patient safety and to effectively confront their own mistakes and those of other technicians, nurses, and physicians.
Additional surveys, completed a minimum of 2 months after training, hinted that staff maintained their sense of “personal empowerment” in regards to patient safety initiatives, Sax commented in a telephone interview with Reuters Health.
Sax and colleagues also found that use of pre-surgery checklists increased from 75 percent in 2003 to 100 percent in 2007 in hospitals that utilized the training course.
Moreover, the community hospital that additionally implemented a Web-based, self-reporting incident and error system modeled after the non-punitive Aviation Safety Reporting System administered by the National Air and Space Administration, saw a marked increase in staff self-reporting of errors.
Per-quarter, self-reports of errors and incidents increased from 709 in 2002 to 1,481 in 2008.
The researchers continue to collect information to better determine which aspects of the course maintain their impact over one-year and which specific measures yield the most benefit in terms of increased patient safety.
Baby aspirin taken for high-risk pregnancy complications does not appear to harm brain development among very premature children assessed when 5 years old, according to a French study. It may actually have some benefit, the study hints.
As this was an observational study, Dr. Stephane Marret from Rouen University Hospital, cautioned in an email to Reuters Health, “it is necessary to confirm our data in other studies.”
Moreover, physicians and pregnant women must always appreciate the potential impact on the developing baby of medications given to mothers during pregnancy, Marret added.
Doctors sometimes recommend baby aspirin to pregnant women at high risk for certain complications. Marret and colleagues assessed the outcomes of 656 infants born prior to 33 weeks of pregnancy to 584 women with pregnancy-related complications, such as high blood pressure, or kidney or immune problems. A total of 125 of these women took low-dose (baby) aspirin for about 12 to 13 weeks while pregnant, the researchers note in the journal Pediatrics.
In outcome assessments conducted 5 years later, Marret’s team found no significant association with any infant or child outcome measures and use of low-dose aspirin during pregnancy.
Among the infants in the study, rates of stillbirth, neonatal death, brain bleeding, and brain injury were similar in baby aspirin-exposed and non-exposed groups.
After allowing for other associated social and medical factors, the researchers likewise noted no neurological impairments associated with low-dose aspirin exposure among the 341 children available for physical, neurological, and psychological examination at the age of 5 years.
Actually, Marret and colleagues saw a trend toward lesser rates of behavioral impairment among the children exposed to low-dose aspirin. Just 12 and 7 percent of this group had hyperactive and conduct problems, respectively, compared with 23 and 14 percent of those not exposed.
The investigators also noted lower overall rates of emotional and peer problems among children exposed to baby aspirin in the womb.
These findings warrant further clinical investigation, Marret and colleagues conclude, particularly in light of a potential neurological benefit among children exposed to low-dose aspirin during gestation.
New study findings offer reassurance to pregnant women that acetaminophen does not appear to raise the risk of birth defects.
Acetaminophen is the active ingredient in Tylenol and certain other painkillers, and is often found in over-the-counter cold and flu remedies. Taken as directed, acetaminophen is considered safe during pregnancy, making it the medication of choice for pregnant women’s body aches and fevers.
However, there are still some questions about whether the drug can contribute to birth defects. Studies looking at birth defects as a broad group have either found no link to acetaminophen use or have yielded inconclusive findings.
Some research, meanwhile, has suggested that the drug may be linked to a higher risk of a birth defect called gastroschisis — but other studies have found no such connection. Gastroschisis refers to a defect in the abdominal wall that allows the intestines to protrude; it has been linked to aspirin use during pregnancy.
In the new study, researchers analyzed data from a large U.S. study that included more than 11,600 children born with congenital defects such as spina bifida, cleft lip and various defects affecting the brain, heart, lungs, limbs and gastrointestinal system. They were compared with 4,500 children born with no major anomaly.
Overall, the study found, there was no evidence linking mothers’ acetaminophen use in the first trimester to a heightened risk of any birth defect.
In fact, women who took the medication to treat a first-trimester fever had a lower risk of certain birth defects — including gastroschisis — than women who did not treat their fevers with acetaminophen.
Researchers led by Dr. Marcia L. Feldkamp, of the University of Utah in Salt Lake City, report the findings in the January 2010 issue of the journal Obstetrics & Gynecology.
The findings, according to the researchers, show that there is “little evidence that single-ingredient acetaminophen increases the risk of a broad range of birth defects.”
They also raise the “intriguing” possibility that lowering a first-trimester fever with acetaminophen cuts the risk of certain defects, Feldkamp’s team writes.
Among women who had fevers in early pregnancy, babies born to those who used acetaminophen had a 65 percent to 83 percent lower risk of certain birth defects of the brain, a 56 percent lower risk of cleft lip and a 59 percent lower risk of gastroschisis.
The researchers note that hyperthermia, or excessively high body temperature, has been implicated in the risks of certain birth defects. More studies, they conclude, are needed to confirm whether treating fevers with acetaminophen does in fact prevent some birth defects.
Drivers who text-message are putting themselves and others in danger as they switch their attention between two complex tasks, a new study confirms.
Researchers who placed young adults in a virtual driving simulator found that the gap between the driver’s car and the car ahead shrank when texting came into the mix, but the driver’s reaction times slowed.
The result: Drivers who were texting were six times more likely to be involved in a virtual ‘crash’ than those who were concentrating just on driving.
Texting seemed to raise the danger factor for drivers more than talking on a cell phone, the researchers noted.
While talking on a cell phone, “drivers apparently attempt to divide attention between a phone conversation and driving, adjusting the processing priority of the two activities, depending on task demands,” wrote the research team, led by Frank Drews, an associate professor of psychology at the University of Utah.
Texting, on the other hand, requires drivers to switch their attention completely to that task, and away from driving, they found, and this made for slower reaction and braking times.
In addition, they found that reading text messages proved more distracting than composing messages.
In the study, reported in the journal Human Factors, Drew and his colleagues had 20 male and female drivers, 19 to 23 years old, engage in either driving or driving while texting in a “high-fidelity [driving] simulator.” All of the participants were experienced texters.
The team found that drivers’ median reaction time increased by 9 percent while they were on a cell phone, vs. 30 percent while texting, compared with the driving-only condition. At the same time, the “minimum following distance” between themselves and the virtual car ahead shrank.
Numerous U.S. cities have banned texting while driving after accidents linked to the practice began to rise.
Ireland’s implementation of a workplace smoking ban in 2004 appears tied to a decline in maternal smoking rates as well as lower risk for preterm births, study findings hint.
Compared with the year prior to the smoking ban, 12 percent fewer women reported smoking during pregnancy in the year after the ban, Dr. Zubair Kabir, of the Tobacco Free Research Institute in Dublin, Ireland, and colleagues report.
Their study, in BJOG: An International Journal of Obstetrics and Gynecology, also revealed “a welcome sign,” Kabir’s team notes. They observed 25 percent lower risk for preterm births in the year after the smoking ban compared with the year prior to the ban.
Kabir and colleagues analyzed records at Coombe Women and Infants University Hospital to assess whether Ireland’s workplace smoking ban altered smoking during pregnancy, a known risk factor for preterm birth and having a low birth weight infant.
Their comparison included 7,593 births in 2003 and 7,648 births in 2005, and allowed for other maternal factors tied to birth risks such as the mother’s age, number of previous births, alcohol intake, blood pressure, and complications during pregnancy.
Overall, babies with the highest birth weights on average were born to former smokers. By contrast, babies with the lowest birth weights had mothers who smoked during pregnancy.
However, in addition to the noted declines in maternal smoking and preterm birth risk, the investigators also identified 43 percent greater risk for low birth weight in the year after the smoking ban compared with the year prior to the ban.
This finding “is intriguing and needs further exploration,” Kabir and colleagues say, particularly in light of evidence that exposures to secondhand smoke during pregnancy may play a role in having babies with low birth weight.
They also call for further exploration of their observed increase in Caesarean delivery rates - from 15.4 in 2003 to 19.5 percent in 2005.
In diabetic patients with blocked coronary arteries, there appears to be no difference in outcomes at one year whether patients undergo bypass surgery or angioplasty with stenting, British researchers report.
Bypass surgery has been the standard treatment for diabetic patients with coronary artery disease. However, less invasive approaches such as angioplasty with stenting — where a thin mesh tube is inserted to open the artery — have emerged. Until now, there’s been little study to see whether the procedure is as effective as bypass in diabetic patients.
“Cardiovascular disease is the leading cause of death among patients with type 2 diabetes, and approximately 25 percent of the patients who undergo revascularization procedures in the United States have type 2 diabetes,” noted Dr. Gregg C. Fonarow, a professor of cardiology at the University of California, Los Angeles, who was not involved in the study.
Earlier studies have suggested that bypass surgery provides more effective revascularization (re-opening of blood flow) and better long-term clinical outcomes in patients with type 2 diabetes and multi-vessel coronary artery disease compared to angioplasty/stenting, Fonarow said.
But this new clinical trial in patients with type 2 diabetes and multi-vessel disease suggests that in the first year at least, bypass and angioplasty/stenting produce similar results, he said.
“However, as this study is small and the follow-up period confined only to the first year, additional studies with more patients and longer-term follow-up are required,” Fonarow said.
The report is published in the Nov. 25 online edition of the Journal of the American College of Cardiology. The study was funded by a number of drug companies, including Eli Lilly & Co. and Bristol-Myers Squibb, as well as stent manufacturers such as Boston Scientific and Medtronic.
For the study, a team led by Dr. Kevin J. Beatt from the Mayday University Hospital in London, randomly assigned 510 diabetic patients who participated in the Coronary Artery Revascularization in Diabetes Trial to undergo coronary bypass surgery or angioplasty with stenting.
During one year of follow-up, the rate of deaths, heart attack and stroke was 10.5 percent among patients who had bypass surgery, compared with 13 percent for patients who underwent angioplasty and stenting, the researchers found.
The type of stent used seemed important. The first group of patients in the trial received bare metal stents, but when drug-eluting (emitting) stents became available many of the patients received them instead. The introduction of these stents greatly improved the outcome for the patients who received them, the researchers found.
While rates for death, heart attack and stroke were 12.4 percent among patients who underwent bypass surgery, they were 11.6 percent among patients who received drug-eluting stents, the researchers report.
“When the new drug-eluting stents were used, stenting seemed as good and was possibly better than bypass surgery,” said Dr. Byron Lee, an associate professor of cardiology at the University of California San Francisco. “However, this finding was based only on a subgroup analysis, and definitive proof will have to await the results of other ongoing trials,” he said.
In cardiac bypass surgery, the patient’s chest is opened, exposing the heart. The patient is put on a heart-lung machine that continues to pump blood though the body as the operation is done. The operation itself involves taking vein segments from the patient’s leg and using them to replace blocked coronary arteries.
In contrast, angioplasty, a minimally invasive procedure, involves passing a catheter from the patient’s groin into the blocked heart artery. A balloon at the tip of the catheter opens to expand the blocked artery. To ensure the artery remains open, a stent is placed in the artery. Drug-eluting stents are coated with a drug that promotes healing and helps prevent the stent from becoming blocked again.
- It’s known that eating a lot of salt puts people at greater risk of high blood pressure. Now there’s confirmation of a corollary: High salt intake also translates to significantly greater risk of cardiovascular disease and stroke.
A review published in the Nov. 25 online edition of BMJ found that a difference of just 5 grams of regular daily salt intake spells a 23 percent difference in the rate of stroke and a 17 percent difference in the rate of cardiovascular disease.
According to the review, the World Health Organization recommends that people consume only 5 grams — about a teaspoon — of salt each day. But people in the West typically eat around 10 grams a day, and those in Eastern Europe consume even more.
The review authors analyzed 13 studies, involving more than 170,000 people, that assessed the link between salt and cardiovascular disease and stroke.
The researchers estimated that reducing daily salt intake by 5 grams around the world could prevent more than 1 million stroke deaths and nearly 3 million deaths from cardiovascular disease each year. And because it’s hard to measure salt intake, those numbers could actually be even higher, the authors noted.