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In a study that supports the widespread use of drugs to help control the AIDS pandemic, researchers said on Wednesday that HIV patients who took the drugs were far less likely to infect their partners.

Using the drug cocktail reduced the likelihood of transmission by 92 percent, the researchers reported in the journal Lancet.

They said the findings mean the drug cocktails known as antiretroviral therapy, or ART, might be a useful prevention tool as well as a treatment.

“These results are … the strongest evidence to date that ART might decrease HIV transmission risk,” said Dr. Connie Celum, professor of medicine and global health at the University of Washington, who worked on the study.

The team analyzed 3,400 couples from seven African countries. In each couple, only one partner was positive for the human immunodeficiency virus, or HIV, which causes AIDS. The team tested couples because they were easier to keep track of.

All of the couples were given counseling on HIV prevention methods, and some were offered HIV drugs when they became available.

During the study, 349 HIV-infected partners were started on HIV drugs. Of the 103 people who became infected during the study, only one caught the virus after the infected partner started taking the drugs.

“These observational data strongly support the hypothesis that ART substantially reduces HIV infectiousness and transmission risk,” Dr. Deborah Donnell of the Vaccine and Infectious Disease Institute at the Fred Hutchinson Cancer Research Center in Seattle and colleagues wrote.

Donnell said the drugs cut the concentration of HIV in the blood to very low levels, which may make people less infectious. In people who took the drugs, the virus was suppressed to very low levels in nearly 70 percent of cases.

A randomized trial is now underway to see if the effect is lasting.

“While awaiting those results, our study indicates that initiation of antiretroviral therapy may have a significant public health benefit as well as clinical advantages for the individuals being treated,” Donnell said in a statement.

She said the findings offer a strong argument for starting treatment for HIV earlier. But even in couples starting treatment late in the disease, the drugs offered benefits.

The AIDS virus infects 33 million people globally and has killed 25 million since the pandemic began in the 1980s. There is no cure and no vaccine but drugs can keep patients healthy.

Without treatment, the virus destroys the immune system, leaving patients susceptible to infections and cancer.

More than 20 drugs are now on the market and can be combined in various ways to control the virus, although it usually mutates eventually and patients must switch to different regimens to keep it under control.

Drugmakers include GlaxoSmithKline, Pfizer, Gilead, Bristol-Myers and Abbott Laboratories.

Helping kids with autism learn how to communicate doesn’t improve their symptoms, British researchers reported at an international meeting on the developmental disorder.

But it does benefit parent-child interaction, the study, which was also published in the journal The Lancet, shows.

“The story is kind of mixed — positive and disappointing,” said Dr. Jonathan Green, of the University of Manchester, who worked on the study.

Autism spectrum disorders affect about 1 in 100 children and cost healthcare systems billions of dollars each year. Green said neither behavioral nor drug treatment had been very successful at improving autistic symptoms, such as poor social skills, slow language development and repetitive behaviors.

But a few smaller studies had suggested that communication-focused treatment — based on recent insights into autism development — might be effective.

So Green and colleagues assigned 152 autistic preschoolers randomly to receive either this treatment or standard care. Throughout a year, they held language-therapy sessions for the treatment group, in which parents learned to adapt their communication to their kids’ impairment.

After one year, they compared the two groups of kids, measuring their symptoms with a widely used test. The treatment turned out not to be effective when accounting for group differences such as age and treatment center.

“The way we designed the trial was to give the treatment a stiff test,” Green told Reuters Health. “We didn’t find what we hoped for.”

Yet children communicated more with their parents after the treatment, said Green, adding that “parents reckoned that the treatment had done a very good job of shifting their children’s symptoms.”

Audrey Thurm, a child psychologist at the US National Institutes of Health, said the new research was more trustworthy than earlier studies.

“We have very few studies that are as rigorous as the study that just came out,” she told Reuters Health.

She added that most US children with autism get treatment similar to the one tested by the British researchers, and that the results should not deter such efforts.

For one, she said, “in child-parent interactions, they did find meaningful changes.” And for another, some children may respond well whereas others might not, canceling out a potential effect.

“Autism is a hard nut to crack,” said Green. “We’ve got ways to go yet.”

Older people might avoid falls if they take off their bifocal or multifocal eyeglasses while taking part in outdoor activities and rely on single-vision lenses instead, a new study suggests.

As people age, they often develop difficulty seeing things at close range, even if they already wear glasses to see at a distance. Instead of using multiple pairs of eyeglasses, they often turn to multifocal lenses — bifocals, trifocals and progressive lenses.

But multifocal eyeglasses can affect balance and increase the risk of falls, research suggests.

For their study, published online May 25 in the BMJ, Stephen Lord, senior principal research fellow at Prince of Wales Medical Research Institute in New South Wales, Australia, and colleagues recruited 606 people over the age of 65 who were at risk of falling and who used multifocal lenses when walking outdoors.

About half of the participants were prescribed a pair of single-lens distance glasses to use when outdoors and in unfamiliar places.

Over 13 months of follow-up, all falls among those who used the single-lens distance glasses fell by 8 percent compared to the control group. Among those who regularly spent time outdoors, falls decreased by about 40 percent. But outside falls increased among those who rarely went outdoors, suggesting that the single-lens glasses aren’t a good alternative for those people.

Fears that removing harmful trans fats from foods would open the door for manufacturers and restaurants to add other harmful fats to foods seem to be unfounded, a new study finds.

A team from Harvard School of Public Health analyzed 83 reformulated products from supermarkets and restaurants, and found little cause for alarm.

“We found that in over 80 brand name, major national products, the great majority took out the trans fat and did not just replace it with saturated fat, suggesting they are using healthier fats to replace the trans fat,” said lead researcher Dr. Dariush Mozaffarian, an assistant professor of epidemiology.

Trans fats — created by adding hydrogen to vegetable oil to make it firmer — are cheap to produce and long-lasting, making them ideal for fried foods. They also add flavor that consumers like, but are known to decrease HDL, or good, cholesterol, and increase LDL, or bad, cholesterol, which raises the risk for heart attack, stroke and diabetes, according to the American Heart Association.

The report, published in the May 27 issue of the New England Journal of Medicine, found no increase in the use of saturated fats in reformulated foods sold in supermarkets and restaurants, Mozaffarian said.

Baked goods were the only exception. Mozaffarian said trans fat was replaced by saturated fat in some bakery items, but they were the minority of products studied. Saturated fats have been associated in research studies with an increased risk of atherosclerosis, diabetes and arterial inflammation.

The big up-front cost to industry is reformulating the product, Mozaffarian said. “When industry and restaurants go through that effort, they are recognizing that, ‘We might as well make the food healthier,’ and in the great majority of cases they are able to do so,” he said. “So, I think that there is greater attention to health than ever before, and industry and restaurants are trying to do the right thing.”

Samantha Heller, a dietitian, nutritionist and exercise physiologist based in Fairfield, Conn., said reformulations that reduce trans fat in foods are good news for consumers.

However, consumers still need to read labels because many foods on the market are still undergoing reformulation, she said, and many others still contain trans fats, also known as partially hydrogenated oils.

“Of concern is the continued and possibly increased use of tropical oils, such as palm, palm kernel and coconut oils, as a replacement for trans fat,” Heller said. For example, it is difficult to find a margarine free of trans fat and tropical oil that one can use for baking and cooking, she said.

Most people know they should reduce their consumption of saturated fats like butter and cheese, but may be unaware that tropical oils in many processed foods are also saturated, Heller said.

Heller suggests consuming healthy fats, such as olive and walnut oils, and unprocessed foods that don’t contain tropical oils.

Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine in New Haven, Conn., said removal of trans fat “from food is a well-justified public health priority.”

This review is reassuring, he said. “In general, trans fat is coming out of food, and saturated fat is not going in. Even when it does, there is apt to be a net health benefit,” he said. Some saturated fat is probably rather harmless, “but that’s a subtlety that dietary guidelines are not yet addressing,” Katz said.

Without intending to, this review raises an issue of importance to the field of public health nutrition, Katz added.

“We often focus on one nutrient at a time and risk improving one nutrient feature, while compromising others,” Katz said. Until a reliable measure of overall nutritional quality is common practice for gauging the merits of reformulation, “reviews such as this will be required to verify that an apparent nutritional advance like trans fat removal is not offset by countervailing retreats,” he said.

SOURCES: Dariush Mozaffarian, M.D., Dr. P.H., assistant professor, epidemiology, Harvard School of Public Health, Boston; David L. Katz, M.D., M.P.H., F.A.C.P.M., F.A.C.P., director, Prevention Research Center, Yale University School of Medicine, New Haven, Conn.; Samantha Heller, M.S., R.D., dietitian, nutritionist, exercise physiologist, Fairfield, Conn.

New research could change the way scientists view the causes — and potential prevention and treatment — of Alzheimer’s disease.

A study published online this month in the Annals of Neurology suggests that “floating” clumps of amyloid beta (abeta) proteins called oligomers could be a prime cause of the disorder, and that the better-known and more stationary amyloid-beta plaques are only a late manifestation of the disease.

“Based on these and other studies, I think that one could now fairly revise the ‘amyloid hypothesis’ to the ‘abeta oligomer hypothesis,’” said lead researcher Dr. Sam Gandy, a professor of neurology and psychiatry and associate director of the Alzheimer’s Disease Research Center at Mount Sinai School of Medicine in New York City.

The new study could herald a major shift in Alzheimer’s research, another expert said.

Maria Carrillo, senior director of medical and scientific relations at the Alzheimer’s Association, said that “we are excited about the paper. We think it has some very interesting results and has potential for moving us in another direction for future research.”

According to the Alzheimer’s Association, more than 5.3 million Americans now suffer from the neurodegenerative illness, and it is the seventh leading cause of death. There is no effective treatment for Alzheimer’s, and its origins remain unknown. For decades, research has focused on a buildup of amyloid beta plaques in the brain, but whether these deposits are a cause of the disease or merely a neutral artifact has remained unclear.

The new study looked at a lesser-known factor, the more mobile abeta oligomers that can form in brain tissue. In their research, Gandy’s team first developed mice that only form abeta oligomers in their brains, and not amyloid plaques.

Based on the results of tests gauging spatial learning and memory, these mice were found to be impaired by Alzheimer’s-like symptoms.

Next the researchers inserted a gene that would cause the mice to develop both oligomers and plaques.

Similar to the oligomer-only rodents, these mice “were still memory impaired, but no more memory impaired for having plaques superimposed on their oligomers,” Gandy said.

Another result further strengthened the notion that oligomers were the prime cause of Alzheimer’s in the mice.

“We tested the mice and they lost memory function, and when they died, we measured the oligomers in their brains,” Gandy said. “Lo and behold, the degree of memory loss was proportional to the oligomer level,” he said.

Gandy noted that PET scans are not able to detect oligomers in the human brain, but they do see amyloid plaques. This could help explain why recent trials of the experimental Alzheimer’s drug bapineuzumab showed a reduction in plaques, but no improvement in patients’ cognitive function, Gandy said.

Bapineuzumab is targeted to amyloid plaques. Whether the drug also affected the oligomers is not known, Gandy said, because the PET scans could not see them. “We don’t even know whether bapineuzumab ’sees’ them,” he said.

The new study could help change the focus of ongoing research. “Our new ‘oligomer only’ mice may enable the development of imaging agents and drugs that lower oligomer levels without having plaques around to muddy the picture,” Gandy said.

Researchers have long been trying to figure out the stages that lead up to plaques and tangles, Carrillo noted. “We [now] know that plaques and tangles are really the end stage of this disease,” she said.

Oligomers are “toxic clumps” that could be the cause of Alzheimer’s disease, Carrillo said. This study confirms for the first time that these toxic clumps are a cause of memory problems, she said.

Carrillo noted that these results also confirm that the disease starts developing 10 to 15 years before it is diagnosed. This understanding could lead to new ways of diagnosing and treating the illness, she added.

“Perhaps future therapeutics attacking oligomers instead of plaques would be a strategy,” Carrillo said.

One expert did have some reservations about that possibility, however.

“The larger unresolved issue is how these oligomers relate to people where plaques accumulate many years prior to disease onset,” said Greg M. Cole, professor of medicine and neurology and associate director of the UCLA Alzheimer’s Center. “One would expect the little oligomer aggregates to arise prior to the bigger plaque aggregates, that is, decades before important memory problems [surface].”

That could mean that “targeting oligomers may work best for prevention,” rather than the treatment of existing disease, he said. “Ongoing efforts to track and specifically target the oligomers in clinical trials with memory deficit patients should soon tell us how much good we can do hitting the oligomers. It may be a huge success or too little, too late.”

SOURCES: Sam Gandy, M.D., Ph.D., professor, neurology and psychiatry, associate director, Alzheimer’s Disease Research Center, Mount Sinai School of Medicine, New York City; Greg M. Cole, Ph.D., professor of medicine and neurology, associate director, Alzheimer’s Center, University of California, Los Angeles; Maria Carrillo, Ph.D., senior director of medical and scientific relations, Alzheimer’s Association;

Despite the common belief that high stress can trigger a stroke, a new study finds no evidence that distressing life events raise the risk of a particularly deadly type of stroke.

The study, published in the journal Stroke, looked at the relationship between stressful life events and the risk of subarachnoid hemorrhage, where a ruptured blood vessel causes bleeding into the space surrounding the brain. It’s estimated that up to half of cases are fatal.

It’s common for people to attribute a sudden medical problem like stroke to stress, noted senior researcher Dr. Craig S. Anderson, of the George Institute of International Health and the University of Sydney in Australia.

In the case of subarachnoid hemorrhage, he told Reuters Health in an email, it is possible for a sudden rise in blood pressure to cause a rupture in an aneurysm — a weakened area in an artery wall. And subarachnoid hemorrhage does sometimes follow a sudden exertion, during exercise or sex, for example, Anderson noted.

However, whether life’s distressing experiences are associated with a higher risk of the strokes has been unclear.

For their study, Anderson and his colleagues interviewed 388 subarachnoid-hemorrhage survivors about distressing life events they had experienced in the one month and one year preceding the stroke.

The survey focused on 12 general types of stressful events — including the death of a family member or friend, job loss or being the victim of a crime.

The survivors’ responses were then compared with those of 473 “control” participants in the same age range who had never suffered a subarachnoid hemorrhage.

Overall, the study found, most forms of stressful life events showed no relationship with the risk of subarachnoid hemorrhage.

When it came to events experienced in the month before the subarachnoid hemorrhage, two types of stressors — financial or legal problems and the catch-all category of “other significant event” — were associated with an increased risk. Ten percent of survivors reported a financial or legal problem over that month, versus 4 percent of the control group.

However, the researchers report, when they accounted for factors like high blood pressure, smoking and drinking, the links between those two stressors and subarachnoid hemorrhage were only “marginally” significant.

In other findings, there was a link between subarachnoid hemorrhage and having been a victim of a physical assault in the past year (reported by 4 percent of survivors and 1 percent of the comparison group). On the other hand, people who had a family member or friend fall ill or suffer an injury in the past year showed a decreased risk of subarachnoid hemorrhage.

It’s likely, according to the researchers, that because the study tested 12 different types of life events, the few that were weakly tied to the risk of subarachnoid hemorrhage were simply chance findings.

The concept of “stress,” Anderson noted, is a difficult thing for researchers to measure. This study took one approach to doing so, which is to look at rates of major events that are often sources of psychological stress. Individual study participants’ actual responses to those events are unknown.

Still, Anderson said that based on the findings, “we can confidently say that ’stressful life events’ are not an important risk factor for subarachnoid hemorrhage.”

In terms of prevention, he said, people should instead focus on avoiding or treating established risk factors for subarachnoid hemorrhage, which include smoking and high blood pressure.

SOURCE: Stroke.

Apparently spurred by concerns about the recently discovered H1N1 swine flu virus, a record number of Americans — especially children and younger adults — got seasonal flu shots during the just-concluded flu season, U.S. health officials reported Thursday.

The increases in seasonal flu vaccinations — which did not offer protection against H1N1 flu — were largely driven by public programs instituted by the U.S. Centers for Disease Control and Prevention to get children and others to receive a seasonal flu shot, as well as the H1N1 vaccine. For the first time, children 5 to 18 were encouraged to get a flu shot this past flu season, CDC officials reported in the April 30 issue of the agency’s Morbidity and Mortality Weekly Report.

CDC officials said the 2010-2011 seasonal flu shot will include a component to protect against the H1N1 flu. Unlike traditional seasonal flu, the H1N1 flu — first identified last spring — strikes children and young adults harder than older adults.

“We are hopeful that those who were vaccinated this year will come back and get vaccinated for next season’s flu,” said study co-author Gary Euler, who’s with the CDC’s National Immunization Program.

Vaccination rates for the 2009-2010 flu season varied state-to-state, particularly among children. Coverage of children averaged 40 percent, compared to 24 percent for the 2008-2009 flu season.

Rates remained stable among recommended adult age groups: 36 percent for people 18 to 49 years of age with high-risk conditions, 45 percent for people 50 to 64, and 68 percent for people 65 and older, the report found.

Among younger adults who did not have high-risk conditions, vaccine coverage averaged 28 percent, seven points higher than last year, the researchers noted.

Euler said that school-based vaccination clinics were particularly effective in increasing vaccination rates among children. And, he added, “if the H1N1 vaccine had been available earlier more people would have been vaccinated.”

Next year will mark the first year when a flu shot is recommended for all Americans, which should lead to even higher vaccination rates, Euler said.

Infectious disease expert Dr. Marc Siegel, an associate professor of medicine at NYU Langone Medical Center, said the 2009-2010 flu season “ended up being a milder flu season than usual, by a long shot, because the H1N1 pandemic flu crowded out the seasonal flu.”

Siegel also pointed to the higher rates of vaccination among children, who, he said, are “super spreaders” of flu. “We ought to be vaccinating every child,” he added.

Siegel said that vaccinating children also protects older adults by limiting potential transmission of the disease. Older people, particularly seniors, are at heightened risk of complications and death from seasonal flu.

Another report in the same issue of the MMWR said that a new flu vaccine containing four times the amount of antigen has been licensed for use in people 65 and older.

Whether this stronger vaccine will improve the immune response of older people isn’t known, the CDC said. The agency’s Advisory Committee on Immunization Practices is waiting for data on the vaccine’s effectiveness before recommending its use.

Siegel said this vaccine could be very useful for some older patients.

“Basically, the elderly end up with less immunity,” he said. “The older you get and the more infirmed you get and the more chronic illnesses you have, the less your overall immunity to flu is.”

Good candidates for the new vaccine would include people with chronic conditions, such as diabetes and respiratory disorders, including chronic obstructive pulmonary disease (COPD), as well as people in hospitals and nursing homes, Siegel said.

About one in five babies born to mothers with hepatitis B aren’t getting treatments that have been shown to prevent the infection in newborns, a new study finds.

Given within 24 hours of birth, the hepatitis B vaccine and hepatitis B immunoglobulin can protect 85 percent to 95 percent of newborns from becoming infected, even if they were exposed at birth.

Researchers from the U.S. Centers for Disease Control and Prevention reviewed medical records of 4,762 mothers and 4,786 infants. The records represented about 25 consecutive live births from 190 U.S. hospitals, each of which was surveyed about their hepatitis B prevention policies in their labor and delivery departments.

Records showed that 18 women tested positive for hepatitis B at the time of admission to the hospital. While 62 percent of their newborns received the hepatitis B vaccine and immunoglobulin, nearly 14 percent left the hospital unvaccinated and nearly 20 percent did not receive immunoglobulin before discharge, according to the study.

Of 320 women whose hepatitis B status was unknown, meaning they may or may not have been tested for the virus, only about 52 percent of their infants were vaccinated within 12 hours of birth. About 20 percent of these babies left the hospitals without being vaccinated.

“A key message of the study is that hepatitis B virus transmission is almost entirely preventable through vaccination and prophylaxis,” said study author Bayo Willis, a CDC epidemiologist. “We really need hospitals to have correct policies in place and to implement those policies so that every newborn is protected before they leave the hospital.”

The study findings were released online March 8 in advance of publication in the April print issue of Pediatrics.

About 1.4 million U.S. residents have chronic hepatitis B infection, which causes from 2,000 to 4,000 deaths annually. Children can become infected during delivery or from household contact with those who are infected, according to background information in the study. The virus spreads through blood or other body fluids.

While many people who contract hepatitis B are able to eventually clear their bodies of the infection, some develop chronic hepatitis, which eventually can lead to cirrhosis and liver cancer.

Children are even more vulnerable to the disease. About 90 percent of children who contract hepatitis B go on to have chronic infections, many of whom will have liver disease by the time they’re in their 20s, said Dr. Kenneth Bromberg, chairman of pediatrics and director of the Vaccine Research Center at The Brooklyn Hospital Center. About 25 percent of them will die prematurely, according to the article.

The CDC recommends infants receive the hepatitis B vaccine at birth, and then receive booster shots at one and six months.

Pregnant women should also be tested for hepatitis B as part of their prenatal care, which is something not all women receive. In those situations, women should be tested upon admission to the hospital, Bromberg said.

Not all hospitals do so routinely, however. Only 67 percent of hospitals had a policy calling for all newborns to receive the hepatitis vaccine, while 63 percent of hospitals said they had a policy of testing women upon admission if there was no documentation of a hepatitis B test.

Nearly 81 percent of hospitals said they would give exposed infants the hepatitis B vaccine within 12 hours and about 77 percent said they would give the immunoglobulin within 12 hours.

“The more the hospital paid attention, the better the outcomes were,” Bromberg said. “The fact that only about 73 percent of hospitals even look at the results of the hepatitis test is pretty atrocious. That means 27 percent of hospitals don’t even look.”

In addition, researchers noted documentation errors in the medical records regarding mothers’ hepatitis B status, such as the mother’s record noting she had hepatitis B but the same information was not included in the infant’s record.

Each year, about 40 to 90 cases of perinatal hepatitis B are reported to the CDC, although the true number may be 10 to 20 times that, according to researchers.

“The greatest predictor of which children would get the hepatitis vaccine was the hospital having a policy for universal vaccination of infants,” Willis said. “Our study shows that gaps still persist in perinatal hepatitis B prevention.”

SOURCES: Bayo Willis, M.P.H., epidemiologist, U.S. Centers for Disease Control and Prevention, Atlanta; Kenneth Bromberg, M.D., chairman, pediatrics, and director, Vaccine Research Center, The Brooklyn Hospital Center, New York City; Pediatrics, online.

Eye doctors can often treat glaucoma successfully if they catch it early, but a new study suggests that ophthalmologists can sometimes wait before treating those at risk of developing the disease.

If their ophthalmologists choose to postpone treatment, certain patients with higher-than-normal pressure in the eye won’t need to take prescription anti-glaucoma eye drops, potentially for years.

“In the past, doctors were left to their own judgment, which is fine,” said study author Dr. Michael A. Kass, chairman of the department of ophthalmology and visual sciences at Washington University in St. Louis. “But it’s nice to have some judgment that’s backed up by some hard evidence.”

Glaucoma, caused when pressure in the eye damages the optic nerve, can lead to impaired vision and blindness. Older people and blacks are at especially high risk.

To measure their risk, ophthalmologists measure eye pressure, often with a puff of air or blue light.

The pressure exists because “there’s fluid produced in the eye, and it needs to filter out. It keeps your eye from being soft and mushy, and allows you to keep the structural roundness necessary for you to see,” explained Dr. Alfred Sommer, a professor of ophthalmology and dean emeritus of the Bloomberg School of Public Health at Johns Hopkins University in Baltimore.

People with higher pressure are at risk of developing glaucoma, and eye doctors can give preventive eye drops to patients when their eye pressure is high. But the drops can be expensive and annoying, Sommer said.

So, what to do with the millions of people in the United States who have high eye pressure with no sign of glaucoma damage?

In the new study, Kass and his colleagues tracked 1,636 people with higher than normal eye pressure. The patients were randomly assigned to be observed or to receive medication.

Patients in the medication group were treated for a median of 13 years. After a median of 7.5 years without treatment, those who were observed received medication for a median of 5.5 years. In the medication group, the risk of developing glaucoma was 16 percent, compared with 22 percent in the observation group.

Some patients “are at low risk, and they don’t seem to benefit much from early preventive treatment. The people who are high risk may benefit,” Kass said.

If glaucoma does develop, it can often be treated through medication, laser treatments and other strategies, he added.

Overall, the findings shouldn’t change how eye doctors currently handle high eye pressure, said Sommer, who wrote a commentary accompanying the new study.

“My own preference, unless someone is a really high-risk outlier, is to just watch them rather than subject them to pressure-lowering medication,” Sommer said.

Patients who are diagnosed with high eye pressure should ask their doctor whether they’re at high risk or if they can just be monitored, he suggested.

However, “you can’t disappear,” he said. “You need to have an examination once a year to make sure there hasn’t been any progression.”

The findings are published in the March issue of the Archives of Ophthalmology.

SOURCES: Michael A. Kass, M.D., chairman, department of ophthalmology and visual sciences, Washington University, St. Louis; Alfred Sommer, M.D., professor, ophthalmology, and dean emeritus, Bloomberg School of Public Health, Johns Hopkins University, Baltimore; Archives of Ophthalmology.

Golfers playing in Vail, Colorado, at 2500 meters (roughly 8200 feet) above sea level, got significantly more burn protection from sunscreen with a sun protection factor (SPF) of 70+ compared to one with an SPF of 15.

“The SPF 70+ formulation was…very effective in protecting skin from sunburns under extreme ultraviolet light and real sporting conditions,” study chief Dr. Darrell Rigel from New York University Medical Center said at AAD 2010, the 68th annual meeting of the American Academy of Dermatology.

“You have to be extra careful at protecting yourself at high altitudes,” Rigel told Reuters Health. “People don’t realize how much additional sun you get at higher altitudes. It’s anywhere from an 8 percent to a 10 percent increase for every thousand feet of elevation. In the summertime, you can get anywhere from 40 percent to 50 percent greater sun intensity than at sea level.”

In the study, 43 people playing golf for an average of 4.5 hours each applied the sunscreen themselves. Twenty-one golfers applied the SPF 70+ sport sunscreen over the entire face before they went out to play golf, and then reapplied the sunscreen about half way through their golf game - about 2 hours into UV exposure - to only one half of the face.

The other 22 golfers applied the SPF 70+ sunscreen to one side of the face and a regular SPF 15 sunscreen to the other side of the face before they went out to play golf.

The researchers monitored the UV conditions to ensure that golfers would have been expected to burn without sunscreen. At the end of the golf games, a dermatologist analyzed the golfers’ faces.

Rigel reported that golfers who started out with the SPF 70+ sunscreen on their entire face and then reapplied it to half the face two hours later had no skin reddening at the end of the 4.5 hours, and none of the golfers who used the SPF 70 formulation complained of sunburn.

In comparison, a significant 7 of 22 golfers who applied SPF 15 to half the face had noticeable skin reddening on that side.

Rigel, who tests sunscreen efficacy for a variety of manufacturers, is against the proposal by the U.S. Food and Drug Administration to limit the SPF of sunscreens to 50.

In a study published last month in the Journal of the American Academy of Dermatology, Rigel and his colleagues reported similar results with ski instructors in Vail, who applied two different sunscreens - one with an SPF of 50 and the other with an SPF of 85 - to different sides of their face. The SPF 50 sunscreen was not enough to protect them from sunburn.

“They put the sunscreen on in the morning, before they went out and skied an average of 5 hours a day and when we evaluated them the next morning, the ones who used the SPF 50 formulation were burned,” he said.

“We sent the results to the FDA because they are considering putting a cap on high SPF. They’ve been thinking of doing this for 2 years now, but they haven’t made their final ruling.”

Also, Rigel said, “People do not typically apply sunscreen in the proper amount, and only use anywhere from 20 percent to 50 percent of the recommended amount. So they are not getting the protection they think they are getting.”

Higher SPF formulations also tend to last longer and be more sensitive, he added.

Finally, “as we showed in the study, an SPF of 50 is not always enough. So if they put a cap on 50, there will be no incentive for sunscreen manufacturers to make a better sunscreen. And that could be the most important reason. Why would you not want the opportunity to have a better sunscreen?”