Archive for the ‘news’ Category
May 17, 2012
Filed Under (news) by admin
Everyone over the age of 50 should be given statins because the “cholesterol-busting” drugs reduce the risk of a heart attack even in healthy people, according to the Daily Telegraph and many other newspapers. The story is based on a systematic review of 27 studies that looked at the effect of lowering “bad” cholesterol (low-density lipoprotein or LDL) using statin therapy in 175,000 people. It found that for every reduction in cholesterol of 1.0mmol/L, taking statins reduced the risk of heart attacks, strokes and other “major vascular events” by about a fifth (21%), even among people without vascular disease or who were at low risk of developing it. Current guidelines recommend prescribing statins for people who have at least a 20% chance of developing cardiovascular disease within 10 years. Doctors normally calculate this risk by looking at a range of factors including the patient’s age, blood pressure, cholesterol levels, whether they smoke and whether they have diabetes. This large review of studies suggests the cholesterol-lowering drugs are suitable for people who don’t have heart or vascular disease and those who are not considered at high risk of developing it. The 21% reduction in risk of heart disease and stroke sounds impressive. However, the number of people who stand to benefit from statins gets smaller as the risk threshold for treatment is reduced. For example, one thousand people at low risk would need to be treated (have a 1mmol/L reduction in bad cholesterol) for five years for 11 of them to benefit. This suggests that someone at low risk may wish to consider whether the possible benefit of taking statins would outweigh the inconvenience. An editorial accompanying the review argues that the current guidelines should be revised so that age is used as an indicator for taking statins (over 50 years old), rather than using expensive screening tests. The commentary forms part of a running debate as to whether middle-aged people without any known risk of cardiovascular disease should be “medicated”, and, if so, how much (whether with statins, aspirin or a “polypill”, as previously suggested).
Where did the story come from?The study was carried out by researchers from Oxford University and the University of Sydney. It was funded by several institutions including the British Heart Foundation, the UK Medical Research Council and Cancer Research UK. The study was published in the peer-reviewed medical journal The Lancet. The study – in particular the commentary arguing for all over-50s to take statins – was covered widely and accurately in most of the media.
What kind of research was this?This was a meta-analysis of individual patient data from 27 trials, which looked at the effects of lowering LDL cholesterol with statin therapy. It included trials of people without vascular disease or at low risk of cardiovascular disease. The authors pointed out that their previous analysis of studies suggested that statin therapy to reduce LDL cholesterol in people without a history of vascular disease ultimately reduced their risk of heart attacks and strokes by about a fifth. However, uncertainty remains as to whether statins have an overall “net benefit” in this group, given that they are at low risk to begin with. The authors said that at least half of all heart attacks and strokes (vascular events) occur among individuals without previous disease. The authors said they have now taken individual patient data from each trial within the database, allowing a more complete assessment of the effects of lowering LDL cholesterol in low-risk individuals.
What did the research involve?The researchers conducted a meta-analysis of data from 175,000 participants in 27 randomised trials, to explore the effects of lowering LDL cholesterol with statin therapy. Trials were included if:
The “major vascular events” the researchers looked at included heart attacks and deaths from heart attacks, strokes and coronary revascularisations (surgery to unblock coronary arteries). They also looked at rates of cancer and the cause of any death that occurred. They grouped the participants into five categories depending on their risk of a vascular event within five years and compared those taking a statin with control groups or with group taking a lower-dose statin. The risk categories were:
The researchers analysed the results using standard statistical methods.
What were the basic results?The researchers found that:
There was no evidence that reducing LDL cholesterol with a statin increased cancer incidence, death from cancer, or deaths from other non-vascular causes.
How did the researchers interpret the results?The researchers calculated that in people with a five-year risk of major vascular events lower than 10%, each 1mmol/L reduction in LDL cholesterol produced an absolute reduction in major vascular events of about 11 per 1,000 over five years. They said this benefit “greatly exceeds any known hazards of statin therapy”. They also pointed out that, under present guidelines, such individuals would typically not be regarded as suitable for statin therapy. They concluded: "The present report shows that statins are indeed both effective and safe for people with a five-year risk of major vascular events lower than 10% who would typically not be judged suitable for statin treatment … and, therefore, suggests that treatment guidelines might need to be reconsidered."
ConclusionCurrent guidelines recommend statins for people who have a 20% or greater chance of developing cardiovascular disease within 10 years. This large review of studies, which further assessed previous research, suggests they may also benefit those without existing cardiovascular disease and those who are not considered at high risk of developing it. However, the individual benefit for those at low risk may be small. Although the study looked at whether statins increased the risk of cancer and death from other causes, it did not include possible adverse effects. Statins are safe drugs that have been associated with a small risk of side effects. As the authors stated, the risk of side effects when giving statins to everyone over the age of 50 would have to be taken into account when calculating the overall benefit. Current guidelines on statin therapy from the National Institute for Health and Clinical Excellence (NICE) will reportedly be updated soon, at which point NICE will take this and any other new evidence into account. There is good existing evidence that a healthy lifestyle (including regular exercise, stopping smoking and a healthy diet) are important factors in cardiovascular health. This study helps answer previous uncertainty about whether apparently healthy individuals could benefit from taking statins.
Links To The HeadlinesGive statins to everyone over 50. Daily Express, May 17 2012 NHS ‘should consider giving statins to healthy people’. BBC News, May 17 2012 Statins could benefit health of millions. The Guardian, May 17 2012 All over 50s should be taking statins. The Daily Telegraph, May 17 2012 Statins ‘could benefit the healthy’. The Independent, May 17 2012 Why EVERYONE over 50 needs to be taking statins: Cholesterol-busting pills cut risk of heart attack or stroke. Daily Mail, May 17 2012
Links To ScienceCholesterol Treatment Trialists’ Collaborators. The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials. The Lancet, May 17 2012 (published online)
May 17, 2012
Filed Under (news) by admin
The Daily Telegraph boldly and erroneously reports that “women really do have a ‘gaydar’ which allows them to tell someone’s sexuality ‘in the blink of an eye’”, while the Sun informs us that “most people have a ‘gaydar’”. This story is based on a study that looked at how accurately people can judge someone’s sexual orientation from their face. In two experiments, researchers investigated how accurately US college students judged whether someone was ‘gay’ or ‘straight’ after quickly glancing at a photo. The research found that students were able correctly to determine sexual orientation slightly more often than could be put down to chance. It found that students were able to identify a woman’s sexuality correctly 65% of the time, and a man’s sexuality correctly 57% of the time. The research suggests that people may unconsciously make judgements about sexual orientation when seeing a face for the first time. Based on this study, the headline that "most people have a gaydar" is misleading. Limited conclusions can be drawn from this small and highly artificial study as accuracy was only just better than chance. In order to draw firm conclusions, larger studies that include people of different ages and from different backgrounds are required. The type of study used does not consider the influence of other factors that could contribute to how a person makes quick decisions about another person’s sexuality and it is not clear whether quick judgements about a person’s sexuality occur in real life. It is important to note that guessing another person’s sexuality may be a sensitive area. This study does not explore the consequences of making quick judgements about another person’s sexuality. It does show that a subjective snap judgement of someone’s sexuality based on their appearance has a good chance of being wrong. Making decisions on such snap judgements is ill advised, even if you think you have a great ‘gaydar’.
Where did the story come from?The study was carried out by researchers from the University of Washington and Cornell University, US. It was funded by grants from the US Association for Psychological Science, Cornell University’s Einhorn Family Charitable Trust Endowment, the Cognitive Science Program, and the College of Arts and Sciences. The study was published in the peer-reviewed online journal Public Library of Science (PLoS) ONE. This study was picked up by a variety of papers and online media and most had attention-grabbing headlines like “gaydar exists”. Apart from the overblown headlines, the Daily Mirror and the Sun reported the details of the study accurately. However, both The Daily Telegraph and Metro misleadingly suggest that the research showed women could judge another person’s sexuality better than men. In fact, the research showed that people were better able to judge whether women were gay or straight, not that women were better able to judge sexuality.
What kind of research was this?This was an observational study that aimed to investigate how people make a judgement about someone’s sexuality based on their face. This was a relatively small study that only investigated the judgements of college students from one US university. Previous research has indicated that there are two ways in which a person perceives a human face – “featural processing” and “configural processing”:
What did the research involve?Researchers undertook two experiments. In the first experiment, they recruited 24 University of Washington students (19 women) in exchange for extra course credits. The students viewed 96 photos of young adult men and women who identified themselves as gay or straight. The participants categorised each face as either straight or gay as quickly and accurately as possible. The photographs were of “white-looking” faces of people reportedly aged 18–29 gathered from Facebook. They included individuals living in 11 major US cities. Photographs were digitally altered to remove hairstyles so that only faces were visible. Faces with facial hair, make-up, glasses and piercings were excluded so as to limit any potential prejudice. Photos were flashed up on a screen for 50 milliseconds (approximately a third of the time it takes to blink the eye). In the second experiment, comprising 129 students (92 women and 37 men), participants were randomly assigned to judge faces that were either upright or upside down. This experiment was designed to judge whether ability to read sexual orientation depends on configural processing (the relationship between features). Results were analysed using statistical methods to determine whether the results were achieved by accurate judgement or whether similar results could have occurred by chance.
What were the basic results?The main finding of this small study was that students were able to determine sexual orientation from glancing at a photo more often than could be put down to chance. (By chance alone it is assumed that people would be correct 50% of the time, like the toss of a coin.) It found that, in the first experiment students were able to identify the sexuality of women’s faces 65% of the time, while they were correct 57% of the time when viewing men’s faces. In the second experiment, the researchers found that when the picture was glanced at upside down, the success rate was less accurate (61% for women and 53% for men). The researchers report that the increase in accuracy for judging upright faces suggests that the ability to read sexual orientation from men’s and women’s faces relies on configural face processing (relationships of facial features) as well as featural face processing (facial features). They say the results also indicate that reading sexual orientation from faces of women is easier than from faces of men.
How did the researchers interpret the results?The researchers conclude that configural face processing significantly affects a person’s perception of sexual orientation and that sexual orientation is easier to detect in women’s faces than men’s faces. The lead researcher, Joshua Tabak, is reported as having said that "we were surprised that participants were above-chance judging sexual orientation based on upside down photos flashed for just 50 milliseconds, about a third the time of an eyeblink". He went on to say that “people of older generations or cultures where homosexuality is not recognised may find it harder to make ‘gaydar’ judgments”.
ConclusionThis small study, carried out in highly artificial conditions, shows that students were able to judge sexuality with greater accuracy than could be put down to chance, and that women’s sexuality was judged more accurately than men’s sexuality. Despite these findings, the study should not be misinterpreted to mean that women are better at accurately judging a person’s sexuality than men. The participants’ judgement was only just better than the results that could have been expected to have been achieved by chance and larger studies that include people of different ages and backgrounds are required to verify these results. It is important to note that, in this study, students were instructed to make forced decisions about a person’s sexuality. It is unclear whether these quick decisions are made in real life situations. In addition, this study does not explore the consequences of making quick judgements about another person’s sexuality. Guessing another person’s sexuality can be a sensitive area. This study highlights the importance of not making snap decisions based on your own subjective judgement of someone else’s sexuality because of the high chance that you may be wrong. It is also worth noting the inaccurate reporting in both The Telegraph’s and Metro’s stories on this research. While the Mirror and the Sun also featured exaggerated headlines, their reporters did a better job of presenting the research. Analysis by Bazian.
Links To The HeadlinesGaydar exists: we can tell who is gay and who is straight in the blink of an eye. Daily Mirror, May 18 2012 Gaydar quick as eye’s blink. The Sun, May 18 2012 Study claims females really do have a ‘gaydar’. Metro, May 18 2012 Women really do have a ‘gaydar’. The Daily Telegraph, May 18 2012
Links To ScienceTabak JA, Zayas V. The Roles of Featural and Configural Face Processing in Snap Judgments of Sexual Orientation. PLoS One. Published online May 16 2012 |
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