Health Technology Research Synopsis 98th Issue Date 22 JAN 11
Compiled By Ralph Turchiano www.vit.bz
Editors Top Five:
To few research articles
In this issue:
- 1. Call for full access to Tamiflu trial data to allow for independent scrutiny
- 2. Common painkillers linked to increased risk of heart problems
- 3. Scientific evidence supports effectiveness of Chinese drug for cataracts
- 4. Why coffee protects against diabetes
- 5. German asthma warning for swimming babies
- 6. Prion disease can spread through air
- 7. Choosing organic milk could offset effects of climate change (There is more on the health benefits)
- 8. Essential oil pill prevents PMS
- 9. Common antibiotics and blood pressure medication may result in hospitalization
- 10. Statins: Benefits questionable in low-risk patients
- 11. Antioxidants may improve chances of conceiving in male subfertility
- 12. Vitamin E may increase the life expectancy of restricted groups of men
13. Montrealers are feeding fish Prozac Public release date: 11-Jan-2011
Call for full access to Tamiflu trial data to allow for independent scrutiny
Tom Jefferson and colleagues from the Cochrane Group argue that the current system for assessing the safety and effectiveness of drugs, based on published trial data only, is “wholly inadequate” and “ethically dubious.”
They propose a new approach that would allow in-depth scrutiny of the complete set of trial data for a new
Their call comes after they reviewed the evidence for the antiviral drug oseltamivir (Tamiflu), and were unable to find sufficient published data to support the conclusion that oseltamivir reduces complications in healthy adults.
As a result, Roche (oseltamivir’s manufacturer) publicly pledged to make full results for ten unpublished clinical trials available for scrutiny. Yet, to date, they have failed to fulfil this promise.
The Cochrane team’s concern deepened after finding reports of ten serious adverse events in patients enrolled in two key manufacturer-funded trials that were not reported in journal publications arising from those trials.
Other recent cases, where the “true” effects of drugs have emerged only after all the evidence (including unpublished data) has been analysed, have further highlighted the importance of independent evaluation.
“The answer is to make the data freely available: we should accept nothing less than a full dataset,” say the authors. “Before licensing a drug – and certainly before large purchase decisions are made – our governments and policy makers should ensure that all researchers can access data in sufficient detail to allow for the independent exploration and re-analysis of trials,” they add.
Their proposed new approach involves compiling a complete list of drug trials (published and unpublished) and requesting full clinical study reports. It is available at http://www.editorial- unit.cochrane.org/neuraminidase-inhibitors-influenza-hta-project
They urge researchers, the public, and the media to work together to put pressure on industry to embrace the ethical responsibility to release data in the public interest. They also call on medical journals to require submission of the most detailed report available.
They conclude: “It is time the media, the Cochrane Collaboration, and any reader interested in knowing what they are prescribing or are being prescribed increase the pressure on policy makers. If you swallow a medication, you need to know how it works – for real.”
Public release date: 11-Jan-2011
Common painkillers linked to increased risk of heart problems
The drugs include traditional non-steroidal anti-inflammatory drugs (NSAIDS) as well as new generation anti-inflammatory drugs, known as COX-2 inhibitors.
The researchers say that doctors and patients need to be aware that prescription of any anti-inflammatory drug needs to take cardiovascular risk into account.
NSAIDs have been the cornerstone of managing pain in patients with osteoarthritis and other painful conditions. In 2004, the COX-2 inhibitor rofecoxib was withdrawn from the market after a trial found that the drug increased the risk of cardiovascular disease. Since then, there has been much debate about the cardiovascular safety of COX-2 inhibitors and traditional NSAIDs, which several studies have not been able to resolve.
So researchers in Switzerland performed a comprehensive analysis of all randomised controlled trials comparing any NSAID with other NSAIDs or placebo.
They included 31 trials and 116,429 patients taking seven different drugs (naproxen, ibuprofen, diclofenac, celecoxib, etoricoxib, rofecoxib, lumiracoxib) or placebo to provide a more reliable estimate of the cardiovascular risks of these drugs than previous studies.
Overall, the number of harmful outcomes that could be compared for placebo versus treatment was low. In 29 trials there was a total of 554 heart attacks; in 26 trials there were 377 strokes, and in 28 trials there were 676 deaths. So the absolute risk of cardiovascular problems among people taking painkillers was low, but the researchers did find that, relative to placebo, the drugs carried important risks.
For instance, compared with placebo, rofecoxib and lumiracoxib were associated with twice the risk of heart attack, while ibuprofen was associated with more than three times the risk of stroke.
Etoricoxibanddiclofenacwere associated with the highest (around four times) risk of cardiovasculardeath.
Naproxen appeared least harmful in terms of cardiovascular safety among the seven analysed preparations.
Although the number of cardiovascular events in the trials was low, the authors say “our study provides the best available evidence on the safety of this class of drugs.” They conclude: “Although uncertainty remains, little evidence exists to suggest that any of the investigated drugs are safe in cardiovascular terms. Cardiovascular risk needs to be taken into account when prescribing any non-steroidal anti- inflammatory drug.”
An accompanying editorial says these cardiovascular risks are worrying because many patients have both cardiovascular disease and musculoskeletal disease, and suggests that it is time for an evaluation of a broader range of alternatives.
Public release date: 12-Jan-2011
Scientific evidence supports effectiveness of Chinese drug for cataracts
Scientists are reporting a scientific basis for the long-standing belief that a widely used non-prescription drug in China and certain other countries can prevent and treat cataracts, a clouding of the lens of the eye that is a leading cause of vision loss worldwide. Their study appears in Inorganic Chemistry, an ACS journal.
In the study, Tzu-Hua Wu, Fu-Yung Huang, Shih-Hsiung Wu and colleagues note that eye drops containing pirenoxine, or PRX, have been reputed as a cataract remedy for almost 60 years. Currently, the only treatment for cataracts in Western medicine is surgical replacement of the lens, the clear disc-like structure inside the eye that focuses light onto the nerve tissue in the back of the eye. Despite the wide use of pirenoxine, there have been few scientific studies on its actual effects, the scientists note.
To fill that gap, the scientists tested pirenoxine on cloudy solutions that mimic the chemical composition of the eye lens of cataract patients. The solutions contained crystallin — a common lens protein — combined with either calcium or selenite, two minerals whose increased levels appear to play key roles in the development of cataracts. Presence of PRX reduced the cloudiness of the lens solution containing calcium by 38 percent and reduced the cloudiness of the selenite solution by 11 percent. “These results may provide a rationale for using PRX as an anti-cataract agent and warrant further biological studies,” the article notes.
Public release date: 12-Jan-2011
Why coffee protects against diabetes
Researchers discover molecular mechanism behind drink’s prophylactic effect By Mark Wheeler January 12, 2011
Coffee, that morning elixir, may give us an early jump-start to the day, but numerous studies have shown that it also may be protective against type 2 diabetes. Yet no one has really understood why.
Now, researchers at UCLA have discovered a possible molecular mechanism behind coffee’s protective effect. A protein called sex hormone–binding globulin (SHBG) regulates the biological activity of the body’s sex hormones, testosterone and estrogen, which have long been thought to play a role in the development of type 2 diabetes. And coffee consumption, it turns out, increases plasma levels of SHBG.
Reporting with colleagues in the current edition of the journal Diabetes, first author Atsushi Goto, a UCLA doctoral student in epidemiology, and Dr. Simin Liu, a professor of epidemiology and medicine with joint appointments at the UCLA School of Public Health and the David Geffen School of Medicine at UCLA, show that women who drink at least four cups of coffee a day are less than half as likely to develop diabetes as non-coffee drinkers.
When the findings were adjusted for levels of SHBG, the researchers said, that protective effect disappeared.
The American Diabetes Association estimates that nearly 24 million children and adults in the U.S. — nearly 8 percent of the population — have diabetes. Type 2 diabetes is the most common form of the disease and accounts for about 90 to 95 percent of these cases.
Early studies have consistently shown that an “inverse association” exists between coffee consumption and risk for type 2 diabetes, Liu said. That is, the greater the consumption of coffee, the lesser the risk of diabetes. It was thought that coffee may improve the body’s tolerance to glucose by increasing metabolism or improving its tolerance to insulin.
“But exactly how is elusive,” said Liu, “although we now know that this protein, SHBG, is critical as an early target for assessing the risk and prevention of the onset of diabetes.”
Earlier work by Liu and his colleagues published in the New England Journal of Medicine had identified two mutations in the gene coding for SHBG and their effect on the risk of developing type 2 diabetes; one increases risk while the other decreases it, depending on the levels of SHBG in the blood.
A large body of clinical studies has implicated the important role of sex hormones in the development of type 2 diabetes, and it’s known that SHBG not only regulates the sex hormones that are biologically active but may also bind to receptors in a variety of cells, directly mediating the signaling of sex hormones.
“That genetic evidence significantly advanced the field,” said Goto, “because it indicated that SHBG may indeed play a causal role in affecting risk for type 2 diabetes.”
“It seems that SHBG in the blood does reflect a genetic susceptibility to developing type 2 diabetes,” Liu said. “But we now further show that this protein can be influenced by dietary factors such as coffee intake in affecting diabetes risk — the lower the levels of SHBG, the greater the risk beyond any known diabetes risk factors.”
For the study, the researchers identified 359 new diabetes cases matched by age and race with 359 apparently healthy controls selected from among nearly 40,000 women enrolled in the Women’s Health Study, a large-scale cardiovascular trial originally designed to evaluate the benefits and risks of low-dose aspirin and vitamin E in the primary prevention of cardiovascular disease and cancer.
They found that women who drank four cups of caffeinated coffee each day had significantly higher levels of SHBG than did non-drinkers and were 56 percent less likely to develop diabetes than were non-drinkers. And those who also carried the protective copy of the SHBG gene appeared to benefit the most from coffee consumption.
When the investigators controlled for blood SHBG levels, the decrease in risk associated with coffee consumption was not significant. This suggests that it is SHBG that mediates the decrease in risk of developing type 2 diabetes, Liu said.
And there’s bad news for decaf lovers. “Consumption of decaffeinated coffee was not significantly associated with SHBG levels, nor diabetes risk,” Goto said. “So you probably have to go for the octane!”
Other authors of the study included Brian Chen, of UCLA, and Julie Buring, JoAnn Manson and Yiqing Song, of Brigham and Women’s Hospital and Harvard Medical School. Funding was provided by the National Institutes of Health. No conflicts of interest were reported by the authors.
The UCLA School of Public Health is dedicated to enhancing the public’s health by conducting innovative research, training future leaders and health professionals, translating research into policy and practice, and serving local, national and international communities.
Public release date: 12-Jan-2011
German asthma warning for swimming babies
BERLIN (AFP) – Germany’s Federal Environment Agency (UBA) on Monday advised parents of babies in families with a history of allergies not to take them to indoor swimming pools because of a risk of asthma.
The agency said that the potential danger lies with nitrogen trichloride, also known as trichloramine, which can be released when chlorinated water reacts with swimmers’ urine, sweat or other organic matter.
“It is not possible at this stage to say definitively whether lung tissue can be damaged in the early stages (of life) and lead to asthma, because data on the effects of trichloramine are lacking,” a statement said.
“Worried parents of children less than two years old in families with high instances of allergies are advised by the UBA to refrain from baby swimming as a precautionary measure until it is clear whether the suspicion is confirmed.”
UBA President Jochen Flasbarth also called on swimmers to better adhere to basic hygiene rules and for swimming pool owners to do all they can to minimise the risk, for example by using the latest water- treatment technology.
“Swimming is healthy for children and adults. In order for it to remain so, everybody should shower thoroughly before swimming in order to prevent dangers to health arising from trichloramine,” Flasbarth said.
A European study published in 2006 by scientists in Belgium found the incidence of asthma and wheezing among 13- and 14-year-olds can rise significantly if they use an indoor swimming pool.
Research carried out in British pools in 2003 found high levels of trichloramine-triggered proteins in the blood of young swimmers and even among parents who had sat by the poolside and not swum.
Asthma has been identified as a worsening health problem around the world, but the suspected causes for it are various.
The finger of suspicion is pointed variously at obesity, genetic predisposition, smoking, low birthweight, air pollution, household dust mites and other allergens. Strong emotions and the weather can exacerbate the condition.
Public release date: 13-Jan-2011
Prion disease can spread through air
13 January 2011 by Debora MacKenzie
You catch flu by inhaling germs – now it seems you can catch prion diseases that way too.
Prions are misshapen proteins that cause brain degeneration in conditions such as mad cow disease and scrapie in animals, and Creutzfeldt–Jakob disease in humans. They can get into you if you eat infected meat or receive infected blood, but it was thought they couldn’t spread through air.
Now Adriano Aguzzi of the Swiss Federal Institute of Technology in Zurich reports that mice exposed for 10 minutes to aerosols containing as little as 2.5 per cent brain tissue from mice with scrapie all developed the disease within months. The prions didn’t need processing by the immune system first, as some other research has suggested, but entered the brain directly through nasal nerves.
“We were amazed at how efficiently they spread,” says Aguzzi. He warns that this doesn’t mean animals or people with prion diseases actually transmit them through the air: there have been no unexplained cases of disease transmission which suggested this. But workers in mills that process potentially infected carcasses may need more respiratory protection.
Labs that test for prions routinely make 10 per cent suspensions of brain tissue, and any handling – pipetting, for example – creates aerosols. Prion labs are not required to use safety equipment that protects workers from aerosols. Aguzzi, who tested his aerosols at the highest level of protection, thinks those labs may now need to rethink safety measures.
Public release date: 16-Jan-2011
Choosing organic milk could offset effects of climate change (There is more on the health benefits)
Wetter, cooler summers can have a detrimental effect on the milk we drink, according to new research published by Newcastle University.
Researchers found milk collected during a particularly poor UK summer and the following winter had
significantly higher saturated fat content and far less beneficial fatty acids than in a more ‘normal’ year.
But they also discovered that switching to organic milk could help overcome these problems. Organic supermarket milk showed higher levels of nutritionally beneficial fatty acids compared with ‘ordinary’ milk regardless of the time of year or weather conditions.
The study, which is published in this month’s Journal of Dairy Science (January 2011), leads on from previous research undertaken nearly three years ago which looked at the difference between organic and conventional milk at its source – on the farms.
“We wanted to check if what we found on farms also applies to milk available in the shops,” said Gillian Butler, who led the study. “Surprisingly, the differences between organic and conventional milk were even more marked. Whereas on the farms the benefits of organic milk were proven in the summer but not the winter, in the supermarkets it is significantly better quality year round.”
There was also greater consistency between organic suppliers, where the conventional milk brands were of variable quality.
“We were surprised to see obvious differences between the conventional brands, with the more expensive ones not necessarily better,” said Mrs Butler. “Some brands – which promote their suppliers as wholesome and grazing on fresh pastures – actually sold milk that appeared to be from very intensive farms.”
Low levels of omega-3 and polyunsaturated fatty acids were discovered in some of these brands, which are indicative of a diet low in fresh grass. These samples also showed evidence of the cows being supplemented with a saturated fat product derived from palm oil.
Mrs Butler puts the differences down to a lower reliance on grazing and fertiliser suppressing clover on conventional farms. “The results suggest greater uniformity of feeding practice on farms supplying organic milk since there were no brands which differed consistently in fat composition,” she said. “This implies a fairly uniform approach to feeding practised across these suppliers.”
Organic dairying standards prescribe a reliance on forage, especially grazing, and, in the absence of nitrogen fertiliser, tend to encourage swards of red and white clover, which have been shown to alter the fatty acid intake and composition of milk.
While protein, antioxidants, vitamins, minerals and some mono and polyunsaturated fatty acids in milk are considered beneficial, saturated fatty acids are believed to have a negative effect on human health.
“We’re always being told to cut down on the saturated fat we consume and switching to organic milk and dairy products provides a natural way to increase our intake of nutritionally desirable fatty acids, vitamins and antioxidants without increasing our intake of less desirable fatty acids,” said Mrs Butler.
“By choosing organic milk you can cut saturated fats by 30-50 percent and still get the same intake of beneficial fatty acids, as the omega-3 levels are higher but omega-6 is not, which helps to improve the crucial ratio between the two.”
While undertaking their research into the differences between organic and conventional milk, the researchers discovered the surprising link between milk quality and our changing climate. Their results suggest that if we continue to have wetter, cooler summers then farmers may have to rethink their current dairy practices.
There was a considerable difference between the milk bought in the first sampling period (July 2006 and January 2007) and corresponding times a year later. The second set of samples, following a particularly wet summer in 2007, was higher in saturated fat and lower in beneficial fatty acids.
“We didn’t expect to find differences between the sampling periods,” said Mrs Butler. “But this is likely to be down to the impact of the weather on availability and quality of forage.”
In North East England, for example, the summer of 2007 was particularly wet, with approximately 30 per cent higher recorded rainfall and 12 per cent lower temperatures compared with 2006.
“These conditions may affect the cows’ behaviour, reducing grazing intake and milk output,” said Mrs Butler. “Farmers also often increase supplementation with concentrated feeds or conserved forage to maintain milk yields in these conditions.”
During the region’s main silage making period (late May until the end of July) rainfall in 2007 was three times higher than the previous year, which also made for poorer quality silage and therefore the need for greater supplementation to compensate in winter diets.
“If these weather patterns continue, both forage and dairy management will have to adapt to maintain current milk quality,” said Mrs Butler. “The higher levels of beneficial fats in organic milk would more than compensate for the depression brought about by relatively poor weather conditions in the wet year.”
The researchers, who are part of the University’s Nafferton Ecological Farming Group and its Human Nutrition Centre, looked at the quality of milk in supermarkets across North East England at varying times of year over a two-year period.
They concluded that organic brands of milk available in supermarkets are higher in beneficial fatty acids such as CLA and omega-3 fatty acids in summer (as in their previous research) and winter (where previous research showed that the difference in the winter was not as noticeable).
Emma Hockridge, head of policy at the Soil Association, said: “This groundbreaking research proves for the first time that people buying organic milk will be benefitting from the higher levels of beneficial fatty acids in organic milk through the whole year.”
Public release date: 16-Jan-2011
Essential oil pill prevents PMS
A pill containing a mix of essential oils has been shown to significantly reduce the symptoms of premenstrual syndrome (PMS). Researchers writing in BioMed Central’s open access journal Reproductive Health tested the tablets by carrying out a randomised, controlled trial in 120 women.
Edilberto Rocha Filho worked with a team of researchers from the Federal University of Pernambuco, Brazil, to conduct the tests. He said, “The administration of 1 or 2 grams of essential fatty acids to patients with PMS resulted in a significant decrease in symptom scores. Furthermore, the administration of the dietary supplement did not result in any changes in the total cholesterol in the patients evaluated”.
Womenwho were given capsules containing 2 grams of a combination of gamma linolenic acid, oleic acid, linoleic acid, other polyunsaturated acids and vitamin E reported significantly eased PMS symptomsat both 3 and 6 months after they began the treatment. Few adverse events were recorded and these were mild, insignificant and did not appear to be directly related to the medication. Speaking about the results, Rocha Filho said, “The negative effect of PMS on a woman’s routine activities and quality of
life may be significant, in addition to the repercussions on economic costs resulting predominantly from a reduction in productivity. Essential oil capsules can now be said to show much promise as a treatment”.
Public release date: 17-Jan-2011
Common antibiotics and blood pressure medication may result in hospitalization
Mixing commonly used antibiotics with common blood pressure medications may cause hypotension (abnormally low blood pressure) and induce shock in older patients, requiring hospitalization, according to a study published in CMAJ (Canadian Medical Association Journal) (pre-embargo link only) http://www.cmaj.ca/embargo/cmaj100702.pdf.
“Macrolide antibiotics (erythromycin, clarithromycin and azithromycin) are among the most widely prescribed antibiotics, with millions of prescriptions dispensed in Canada each year.” writes Dr. David Juurlink, Scientist at the Sunnybrook Research Institute and the Institute for Clinical Evaluative Sciences with coauthors. “The drugs are generally well-tolerated, but they can cause several important drug interactions.”
This study was conducted among Ontarians 66 years and older who were treated with a calcium-channel blocker (drugs often used to treat high blood pressure) between 1994 and 2009. The researchers then identified those who were hospitalized for low blood pressure and, in that group, whether or not a macrolide antibiotic had been prescribed shortly beforehand.
The researchers identified 7100 patients hospitalized for low blood pressure or shock while taking a calcium channel blocker. Treatment with erythromycin was found to increase the risk of low blood pressure almost 6-fold, while clarithromycin increased the risk almost 4-fold. In contrast, azithromycin did not increase the risk of hypotension.
“In older patients receiving calcium channel blockers, the two macrolide antibiotics erythromycin and clarithromycin are associated with a major increase in the risk of hospitalization for hypotension,” conclude the authors. “However, the related drug azithromycin appears safe. When clinically appropriate, it should be used preferentially in patients receiving a calcium channel blocker.”
Public release date: 18-Jan-2011
Statins: Benefits questionable in low-risk patients
There is not enough evidence to recommend the widespread use of statins in people with no previous historyofheart disease, according to a new Cochrane Systematic Review. Researchers say statins should be prescribed with caution in those at low risk of cardiovascular disease (CVD).
CVD is the most common cause of death, accounting for nearly a third of all deaths worldwide. Cholesterol-lowering statins are first line treatments for heart patients and the benefits are well established. However, there is less evidence that statins are beneficial for preventing heart problems in those who have no history of CVD. Given that low cholesterol has been shown to increase the risk of death from other causes, statins may do more harm than good in some patients.
The researchers reviewed data from 14 trials involving 34,272 patients. Outcomes in patients given statins were compared to outcomes in patients given placebos or usual care. Combined data from eight trials
98th Health Research Technology Report 10
involving 28,161 patients that provided data on deaths from all causes showed that statins reduced the risk of dying from 9 to 8 deaths for every 1000 people treated with statins each year. Statins reduced fatal and non-fatal events, including heart attack, stroke and revascularization surgery, as well as blood cholesterol levels.
However, the researchers say that the conclusions of their review are limited by unclear, selective and potentially biased reporting and that careful consideration should be given to patients’ individual risk profiles before prescribing statins.
“It is not as simple as just extrapolating the effects from studies in people who have a history of heart disease,” said lead researcher Fiona Taylor, from the Cochrane Heart Group at the London School of Hygiene and Tropical Medicine in London, UK. “This review highlights important shortcomings in our knowledge about the effects of statins in people who have no previous history of CVD. The decision to prescribe statins in this group should not be taken lightly.”
Theresearcherspoint out thatallbut one ofthe trials theyreviewed were industry-sponsored. “We know that industry-sponsored trials are more likely to report favourable results for drugs versus placebos, so we have to be cautious about interpreting these results,” said Taylor. “The numbers eligible for treatment with statins are potentially great so there might be motivations, for instance, to stop trials earlier if interim results support their use.”
A separate Cochrane Systematic Review, conducted by some of the same authors, considered the effects of combined approaches to reducing the risk of heart disease, including using education and counselling to encourage people to change their diets and stop smoking. The authors concluded that combined interventions had little or no impact on deaths or disease caused by CVD. In an editorial accompanying the reviews, Carl Heneghan, University of Oxford, concluded that, “Although various multiple prevention strategies exist, the most effective and cost-effective intervention for primary prevention in adults at low risk currently remains unclear.”
Public release date: 18-Jan-2011
Antioxidants may improve chances of conceiving in male subfertility
Antioxidant supplements may benefit couples who have difficulty conceiving naturally, according to a new systematic review published today in The Cochrane Library. The review provides evidence from a small number of trials that suggest the partners of men who take antioxidants are more likely to become pregnant.
Male subfertility affects one in 20 men. Chemicals called reactive oxygen species (ROS) are said to cause damage to cells, and in particular sperm cells, which may result in lowered sperm counts and interfere with their ability to fertilise eggs. Antioxidants include natural and synthetic chemicals, including certain vitamins and minerals, which help to reduce the damage caused by ROS.
The review focused on 34 trials involving 2,876 couples undergoing assisted reproductive techniques such as in vitro fertilisation and sperm injections. Most men in the trials had low sperm counts or low sperm motility. The trials explored the use of many different types of oral antioxidants, including vitamin E, L- carnitine, zinc and magnesium.
Compared to controls, a couple was more likely to have a pregnancy or live birth if the man took antioxidants. However, these results are based on just 964 of the couples in the review for pregnancies and 214 couples for live births. Other trials tested the effects of antioxidants on sperm motility and
concentration and showed mostly positive effects, although study group sizes were small.
“When trying to conceive as part of an assisted reproductive program, it may be advisable to encourage men to take oral antioxidant supplements to improve their partners’ chances of becoming pregnant,” said lead researcher Marian Showell, who works in Obstetrics and Gynaecology at the University of Auckland in Auckland, New Zealand. “However, these conclusions are currently based on limited evidence.”
There were not enough data comparing different antioxidants to reach any conclusions about the relative effectiveness of supplements. “We need more head-to-comparisons to understand whether any one antioxidant is performing better than any other,” said Showell.
Public release date: 20-Jan-2011
Vitamin E may increase the life expectancy of restricted groups of men
Depending on the level of smoking and dietary vitamin C intake, vitamin E supplementation may extend the life-span of restricted groups of men, according to a study published in the Age and Ageing.
Several large randomized trials of humans found that vitamin E supplementation does not reduce mortality. However, the average effect on mortality in a group of people with a wide age range may mask an effect of vitamin E on the life-span.
Dr. Harri Hemila, and Professor Jaakko Kaprio, of the University of Helsinki, Finland, studied the age- dependency of vitamin E effect on mortality in the large randomized trial (Alpha-Tocopherol Beta- Carotene Cancer Prevention Study) which was conducted in Finland between 1985-1993. Their study was restricted to follow-up period over 65 years and 10,837 participants contributed to the analysis.
Among all analyzed participants, vitamin E had no effect on mortality when participants were 65 to 70 years old, but reduced mortality by 24% when participants were 71 or older.
Among 2,284 men with dietary vitamin C intake above the median who smoked less than a pack of cigarettes per day, vitamin E extended life-span by two years at the upper limit of the follow-up age span. In the other participants, consisting of 80% of the cohort, vitamin E did not affect mortality, which shows that vitamin E is no panacea for extending life expectancy.
The researchers concluded that “if vitamin E influences the life-span, it is possible that a benefit on the oldest participants might be camouflaged by the large middle-aged majority of study participants”.
Therefore, they propose that it might be useful to analyze the effect of vitamin E supplementation in large controlled trials by the age of the participant at the follow-up and not just by the time after randomization that has been customary.
Public release date: 21-Jan-2011
Montrealers are feeding fish Prozac
Research shows influence on brain activity while long-term consequences are unclear
Aroundonein four Montrealers take some kind of anti-depressant, and according to new research, the drugs are passing into the waterways and affecting fish. The findings are internationally significant as the
city’s sewage treatment system is similar to that in use in other major cities, and moreover, it is reputed to be the third largest treatment system in the world. Lead by Dr. Sébastien Sauvé at the University of Montreal’s Department of Chemistry and André Lajeunesse, a PhD candidate, the research team found that the drugs accumulate in fish tissues and are affecting the fish’s brain activity.
The Saint Lawrence is a major international waterway that connects the Atlantic Ocean to the Great Lakes, and it surrounds the island of Montreal. Sauvé has been looking at the chemical pollution of the water system for years. “Montreal has a very basic sewage system – the city basically only removes solids, there’s no disinfecting of the water,” he explained. “In any case, the chemical structure of anti- depressants makes them extremely difficult to remove from sewage, even with the most sophisticated systems available.”
“We know that antidepressants have negative side effects on human beings,” Sauvé said, “but we don’t know how exactly how these chemicals are affecting the fish, and by extension, the Saint Lawrence River’s ecosystem.” Despite a lack of information about the possible toxicity brought from these substances, the research group suggests an interesting tool to track the early biological effects of antidepressants. “Since the acute toxicity of antidepressants is less probable toward aquatic organisms, chronic toxicity remained possible. In this way, the suggested biomarker involved in the serotonin regulation in the brain may represent a promising means of determining subtle biological effects to fish,” explained Lajeunesse. Chronic toxicity means harm resulting from long-term exposure, whereas acute relates to more immediate harm following a single high-dose incident. Serotonin is an important chemical that plays a role in feelings of happiness – it’s sometimes referred to as the “happy hormone.”
Sauvé was quick to point out that there is no immediate danger to humans. “The amount of anti- depressants being released into our river works out to roughly the equivalent of a grain of salt in an Olympic-size swimming pool,” he said. “That’s not enough to affect people, should they are brave enough to go fishing out there – I’d be more worried about the trace metals! Nevertheless, we are seeing an impact on the river’s ecosystem, which should concern cities everywhere.” Further research by other teams will look at exactly what the consequences might be.
These reports are done with the appreciation of all the Doctors, Scientist, and other Medical Researchers who sacrificed their time and effort. In order to give people the ability to empower themselves. Without the base aspirations for fame, or fortune.
Just honorable people, doing honorable things.