Medical News

New research in mice suggests that a commonly used drug combination might protect people from being infected by the AIDS virus through the major routes of transmission.

Previous research showed that the drugs could prevent vaginal transmission. In this study, the medication prevented HIV infection through anal sex and intravenously.

The research raises the prospect that “one single pill once a day, totally available in the pharmacy for patients, can be used to prevent transmission by any mode anywhere in the world,” said J. Victor Garcia-Martinez, a professor of medicine at the University of North Carolina at Chapel Hill and senior author of a study published online Jan. 20 in PloS One.

But there’s no guarantee that the drugs will protect people, even though the mice had “humanized” immune systems. And the idea of preventing HIV transmission through medication raises a host of issues.

The drug in question, Truvada, is a combination of the medications tenofovir and emtricitabine. It’s used to treat people with AIDS and to stop HIV infection from setting in after exposure to the virus. In hospitals, doctors and nurses sometimes take it after getting stuck with a needle that might be contaminated.

Garcia-Martinez and his colleagues previously found that the drug prevented vaginal transmission of HIV in mice. In the new study, they examined mice known as “BLT” because human bone marrow, liver and thymus cells had been transplanted into their bodies, giving them what the researchers consider to be a human immune system.

Some mice got doses of Truvada and others did not; all were exposed to HIV rectally or intravenously at a higher level than typical in human exposure. Of the 17 mice given Truvada, only one — which had been exposed intravenously — became infected.

By contrast, several mice that did not take Truvada became infected.

The drug works by preventing the virus from making more virus in the body, Garcia-Martinez said.

“The biggest caveat is that even though we’re using humanized mice, this is not a human being,” he said. On the other hand, studies in humans should let researchers know soon if it works in people, and the mice research helps scientists “get a handle on what the virus will do in humans,” he said.

So why not give Truvada to everyone at risk for HIV infection, such as people who have many sex partners?

For one thing, the drug is expensive, costing hundreds of dollars a month. And there’s concern that people would take more sexual risks if they were to take the drug, potentially robbing the medication of its infection-preventing power if it’s not 100 percent effective.

Side effects could be a problem too, as could forgetting to take the drug.

Even so, the idea of a preventive drug treatment — a “chemical condom,” as some call it — might not be out of the question.

“It’s reasonable to think that this might one day prove to be a strategy you could use,” said A. David Paltiel, a professor who studies HIV issues at the Yale School of Medicine.

SOURCES: J. Victor Garcia-Martinez, Ph.D., professor, medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, N.C.; A. David Paltiel, Ph.D., professor, public health, and acting head, division of health policy and administration, Yale School of Medicine, New Haven, Conn.

“Out of control” binge eaters who get help from a therapist do better in the short-term than people who use self-help techniques, new research shows.

But in the long-term, self-help and therapist-led or therapist-assisted approaches seem to have about the same effectiveness, Dr. Carol B. Peterson of the University of Minnesota in Minneapolis and her colleagues found.

Binge eaters often eat large amounts of food while feeling a loss of control over their eating. It is different from the binge-purge syndrome of bulimia because binge eaters do not purge afterward by vomiting or taking laxatives. Binge eating disorder is contributing to the rise in obesity.

While medications can help reduce bingeing episodes among people with the disorder, psychotherapy is the most effective approach to treatment, Peterson and colleagues note in a report in the latest issue of the American Journal of Psychiatry. Self-help interventions have also shown promise.

Peterson’s team compared the effectiveness of various group therapy approaches by randomly assigning 259 adults with binge eating disorder to 20 weeks of therapist-led, therapist-assisted, or self-help group therapy, or to a waiting list.

After treatment, just over half of people who had therapist-led group treatment were abstaining from bingeing, compared to a third of those in the therapist-assisted groups, 18 percent in the self-help groups, and 10 percent in the waiting list group. The frequency of binge eating was also lower in the therapist-led or assisted groups compared to the self-help group or the waiting list group.

When the researchers followed up 6 and 12 months after treatment ended, they found no difference in bingeing abstinence rates or binge eating frequency among the groups.

However, the study participants who got help from therapists were more likely to stick with the treatment for 20 weeks; 88 percent of people in the therapist-led groups and 81 percent of those in the therapist-assisted groups completed 20 weeks of treatment, compared to 68 percent of people in the self-help groups.

“The presence of a therapist may enhance short-term abstinence and reduce the likelihood of dropout,” Peterson and her team say. But self-help groups may be helpful when therapists aren’t available, they add.

“These findings suggest that self-help group treatment may be a viable alternative to therapist-led interventions in some settings,” Dr. Walter Kaye of the University of California San Diego writes in an editorial accompanying the study.

“It should be noted, however, that the power of such treatments may be limited since many patients continued to have substantial degrees of binge behaviors at 12-month follow-up,” Kaye notes.

A new analysis of studies including nearly 80,000 people aged 60 and older confirms that certain types of widely prescribed drugs, such as antidepressants and sedatives, can increase their risk of falling.

Falls often have serious consequences for older people, such as injuries leading to disability and admission to a nursing home, or even death.

While prescription drugs are recognized as contributing to fall risk among older people –who are likely to be on lots of medications — discovering just which drugs are the problem is still a “challenge,” Dr. Carlo A. Marra of the University of British Columbia in Vancouver and colleagues note in the Archives of Internal Medicine.

To update a review of studies on this subject published in 1996, Marra and his team identified 22 studies published between 1996 and 2007 including 79,081 people 60 and older, some of whom lived independently, and some of whom were institutionalized. They analyzed the risk of falling associated with nine classes of drugs.

Three classes turned out to significantly boost fall risk: sedatives and hypnotics, typically prescribed as sleeping aids; antidepressants; and benzodiazepines, which include tranquilizers like Xanax and Valium.

The researchers also saw an increased risk in patients taking non-steroidal anti-inflammatory drugs — like aspirin– and drugs for treating psychosis, but they note that people may be taking these drugs to treat conditions that would in and of themselves increase their risk of falling.

Prescription drug use among the elderly is on the rise, Marra noted in an interview with Reuters Health. He pointed out that one recent Canadian study found 1 in 7 people over 80 had filled a prescription for an antidepressant.

Older people who are taking any of the drugs associated with falls should talk about the medication with their physician and their pharmacist, Marra advised.

“Perhaps between their practitioner and themselves they can come up with safer alternatives,” Marra said.

U.S. researchers say they’ve identified a protein that causes nasal and sinus polyps in 15 percent to 30 percent of people with chronic sinusitis.

The condition is one of the most serious forms of sinusitis, a constant irritation and swelling of the nasal passages. Polyps – unhealthy overgrowths of sinus tissue — can block the sinus passages and make it difficult or impossible to breathe through the nose. This often leads to pain, swelling and infections.

“This type of sinusitis isn’t subtle — you can spot the patients with polyps across the room. They’re breathing through their mouths, they talk with nasal voices, they’re constantly sniffling, and their faces are swollen,” Dr. Jean Kim, an assistant professor in the departments of otolaryngology and allergy and clinical immunology at the Johns Hopkins University School of Medicine, said in a news release.

Kim and colleagues analyzed sinus tissue from patients and concluded that a protein called vascular endothelial growth factor (VEGF) — which is known to stimulate blood vessel growth — causes the cell overgrowth that causes the polyps.

The protein may offer a target for new treatments for the condition, which typically resists all current therapies. Surgery is a common treatment but the polyps nearly always regrow. Oral steroids only temporarily treat the problem and have a number of harmful side effects.

“In the future, we might have a nasal spray with an anti-VEGF agent in it,” Kim said.

Getting a patient’s family history is widely regarded as a standard element of good medical care. But a report published today concludes that there isn’t much good evidence that obtaining such information improves doctors’ ability to predict and manage disease.

In addition, the report’s authors say the best way to collect family history data is unclear, as is the impact on patient outcomes and behaviors.

Dr. Brenda J. Wilson, from University of Ottawa, Ontario, Canada and colleagues did a study of previous studies on the subject, and report their findings in the online version of the Annals of Internal Medicine.

They found only two studies that tried to determine whether accurate family histories were likely to have an impact on care, and those studies had a number of limitations.

They found more studies of how patients reported their family histories. In 23 studies, they saw evidence that patients were more accurate about reporting the absence of disease in relatives than the presence of disease. Perhaps not surprisingly, patients were more accurate about their first degree relatives than their distant relatives.

The study was funded by the Agency for Healthcare Research and Quality.

Restless legs syndrome, a neurological disorder characterized by a strong urge to move the legs, is much more common among some racial groups than others, a new U.S. study has found.

Researchers interviewed 190 people being seen at a primary care clinic. About 12 percent of those who were black, compared with 36 percent of those who were not black, were found to have restless legs symptoms. Overall, the prevalence of restless legs was 23 percent among the clinic participants.

Among blacks, the prevalence of restless legs syndrome (RLS) was 12 percent for both men and women, compared with 40 percent for women and 29 percent for men among the others, most of whom were white.

“There are significant ethnic differences in the prevalence of restless legs syndrome, but the exact causes of higher prevalence among Caucasians are unknown,” study author Dr. Ammar Alkhazna, of the University of Missouri, said in a news release from the American College of Chest Physicians. “This likely reflects a combination of factors, including a genetic predisposition to RLS, diet, including iron intake, medications, and possibly culture.”

The study was scheduled to be presented at the annual scientific meeting of the American College of Chest Physicians, held Oct. 31 to Nov. 5 in San Diego.

Symptoms of restless legs also were seen more often in women than men, the study found.

“Some risk factors for restless legs syndrome appear to be more common among women,” Alkhazna said. “Women are more likely to be iron-deficient than men and have rheumatoid arthritis, which are known risk factors for RLS.”

That friend who stays thin despite eating anything and everything is not just annoying. She might also wreck your diet, new research suggests.

Researchers found that when they had college students watch a movie and snack with either a skinny or overweight companion, the students typically followed the thin friend’s lead when she overindulged.

In contrast, study participants used more self-control when snacking with a heavier companion who overate.

The findings, published in the Journal of Consumer Research, suggest that seeing a thin friend devour a big meal gives us implicit permission to do the same.

“We think ‘if she can eat like that and stay thin, so can I,’ or ’she is having cake, then I can too,’” explained Dr. Brent McFerran, an assistant professor of marketing at the University of British Columbia in Kelowna, Canada.

“In other words,” he told Reuters Health in an email, “the most dangerous person to eat with is not someone who is obese, but a thin friend with a large appetite.”

For their study, McFerran and his colleagues recruited 210 female college students for what the participants believed was a study on movie viewing; each woman watched a movie with a companion, who was actually a member of the research team.

In some cases, the researcher showed up as her normal 105-pound self, while in others she donned padding that made her appear to be obese.

During the movie, the pairs were offered snacks, with the undercover researcher taking her portion first.

In general, McFerran’s team found, the students ate more when their thin companion took a large portion, versus cases where the “obese” companion took a similarly large portion.

For example, when the skinny researcher ate a lot (30 candies), the participants ate an average of 10 candies. When the researcher was “obese” and ate a lot, the kids ate about 6 candies.

“Eating involves much social pressure,” McFerran said, noting that social influences may, in fact, be the strongest predictor of what we eat.

But the current findings do not mean that we need to cancel all future dinner plans with our overindulgent skinny friends.

“If we think about what we are doing in advance,” McFerran said, “we are less likely to overconsume.”

He suggested that instead of looking at a thin friend who is gorging on dessert and feeling permission to do the same, we should remind ourselves that individuals are different — with different metabolisms and exercise habits, for example.

Focus on your own goal to eat healthfully, McFerran said, rather than automatically mimicking a friend.

He pointed out, however, that there is a “flip side”: Friends who choose smaller portion sizes and healthier foods can encourage us to do so, especially if those friends are thin.