Written by admin on Thursday, June 30th, 2011 in Swine Flu.
NEW YORK (Reuters Health) – The swine flu shot appears to be safe for pregnant women, according to a new government report that tallies health problems occurring after the vaccinations.
Written by admin on Thursday, June 30th, 2011 in Swine Flu.
“Fidgeting makes you fit,” according to the Daily Express. The news is based on a study that examined the association between a measure of heart and lung fitness (cardiorespiratory fitness or CRF) and the amount of physical activity that obese, inactive people got through everyday activity, rather than exercise.
It is generally accepted that CRF predicts the risk of heart disease, stroke or death from any cause. Current guidelines suggest that certain levels of moderate physical activity, sufficient to cause mild breathlessness for example, are needed to maintain heart and lung fitness. Researchers sought to examine whether other types of lower level activity had an impact on CRF as well.
Researchers concluded that lower levels of activity, termed incidental physical activity, were associated with improvements in CRF, although the changes seen were relatively small. As the study involved a small group of inactive, obese individuals in Canada, it is unclear whether the results can be applied to other groups of people.
While physical activity is an important part of a healthy lifestyle, the results of this study are not sufficient to alter current guidelines on recommended activity levels and don’t support fidgeting as a way of getting fit.
The study was carried out by researchers from Queen’s University in Canada. It was funded by the Canadian Institute of Health Research, and was published in the peer-reviewed journal Medicine & Science in Sports & Exercise.
The findings of this study were generally overstated by the media. While newspapers reported health benefits from fidgeting, the study concerned incidental physical activity (IPA), which includes actions such as walking or lifting objects that a person might do as part of their daily routine. Also, the association between IPA and cardiorespiratory (heart and lung) fitness was quite small, and was generally driven by IPA that involved moderate physical activity (such as walking at a comfortable pace). The commonly reported finding that 30 minutes of light exercise, such as jiggling one’s legs while sitting, can improve cardiovascular fitness misinterprets the study’s findings.
This cross-sectional study examined the association between daily activity and cardiorespiratory fitness (CRF).
Researchers report that moderate and high levels of CRF are linked to a reduced risk of cardiovascular disease and death from all causes. They say previous studies have examined the impact of physical activity on CRF by getting individuals to fill out questionnaires about the amount and level of physical activity they do. These questionnaires, however, may not accurately reflect a person’s activity, as specific events may be difficult to remember or estimate and because people generally only report intentional exercise as opposed to incidental daily activities.
Researchers sought to examine the association between physical activity and CRF using more objective measures of activity. The researchers believed that engaging in incidental physical activity might be sufficient to improve CRF.
Canadian men and women aged 35–65 years old were recruited to participate in the study. They were abdominally obese non-smokers who considered themselves to be inactive. Abdominal obesity was defined as having a waist circumference greater than 102cm for men and 88cm for women. They were asked to wear a device called an accelerometer, which detected and recorded physical activity each minute. Participants had to wear these devices for at least 10 waking hours a day on at least four consecutive days. Participants also recorded the time that they went to bed at night and woke up in the morning. Researchers used these self-reports to verify the data recorded by the accelerometer.
Each participant completed a treadmill test in order to measure their CRF. In this test, the participants were asked to exercise to their maximum ability on a treadmill while oxygen consumption was recorded. This method is an accepted way of measuring a person’s overall fitness.
Different forms of activity were classified as incidental physical activity (IPA), low physical activity (LPA) or moderate physical activity (MPA). Researchers then analysed the accelerometer data and, for each day, determined the:
Researchers then compared participants’ activity duration and intensity with their CRF.
Researchers found that:
When the association between duration and intensity of activity and CRF was assessed, researchers found that:
Researchers concluded that the association between incidental physical activity and CRF has important clinical and public health implications, given the previously established link between CRF and cardiovascular disease. They concluded that routine, sporadic activity done throughout the day is beneficial to CRF. This is contrary to current thinking, including US physical activity guidelines, that a threshold of activity must be reached before beneficial changes can be seen.
However, researchers say that although they found an association between incidental physical activity and CRF, the average intensity in their study was low and most of the association was driven by sporadic moderate physical activity. They say the average accelerometer values were associated with walking at a slow, leisurely pace (less than 5.0km an hour), while sporadic MPA was equivalent to walking at a comfortable pace (5.8km an hour).
Researchers also point out that, despite the positive associations found in their study, most participants only had peak CRF values at the low end of the healthy range. They suggest that further research is needed to repeat these results in a broader sample of people, and to assess whether changes in CRF translate into changes in cardiovascular disease risk factors.
This small, cross-sectional study described associations between objectively measured activity levels and cardiorespiratory fitness (CRF) in inactive, obese people. While cross-sectional studies are appropriate for determining associations between different factors, they cannot determine a cause-and-effect relationship. In this particular study, there is no way of knowing whether increased activity levels caused increases in CRF, or whether individuals who had greater CRF were more likely to engage in more activity throughout the day.
While researchers found a statistically significant association between incidental physical activity (or fidgeting, as reported in newspapers) and CRF, the effect was quite small and CRF scores were on the low end of the range. Additionally, most of the association was driven by short periods of higher activity levels.
While any physical activity may be better than none at all, this research does not provide sufficient evidence to alter guidelines for recommended levels of activity. It is likely that some degree of exertion is required in order to improve fitness, and the idea that fidgeting alone makes you fit is a misinterpretation of this research.
Analysis by Bazian
Fidget your way to fitness: Jiggling your legs or getting up to make a cuppa is good for your health. Daily Mail, June 30 2011
Fidgeting makes you fit. Daily Express, June 30 2011
McGuire KA, Ross R. Incidental Physical Activity Is Positively Associated With Cardiorespiratory Fitness. Medicine & Science in Sports & Exercise, 2011
Written by admin on Thursday, June 30th, 2011 in Swine Flu.
Motivational text messages sent to smokers’ mobile phones can double their chances of giving up tobacco, reported The Guardian.
The story is based on a large UK study that looked at whether a six-month programme of supportive text messages could help smokers quit. It compared a group who received positive messages to another group who were given details of other support programmes. At six months, those receiving texts were twice as likely to quit, with a quitting rate of 10.7% compared to the other group’s rate of 4.9%.
This large, well-designed study took several steps to ensure the accuracy of its results. For example, saliva tests were used to verify how accurately people had reported their non-smoking and, in their analyses, the researchers counted people who dropped out of the study as failing to quit. While the quit rate was relatively low in both groups, the researchers say it was comparable to the number of people who succeed using other forms of help, such as counselling.
As a relatively cheap intervention that could reach large numbers of people, text messaging is potentially cost effective, an issue the authors will address in a forthcoming study. The trial did not directly compare text messaging with other methods for quitting smoking, such as nicotine replacement therapy or behavioural support, so text messaging still needs to be assessed in relation to existing treatments.
The study was carried out by researchers from London School of Hygiene and Tropical medicine, the University of Auckland in New Zealand, and the George Institute at the University of Sydney in Australia. It was funded by the UK Medical Research Council, Cancer Research UK and the Primary Care Research Networks. The study was published in the peer-reviewed medical journal The Lancet.
Generally, the media reported the story accurately. The BBC included comments from independent experts.
This randomised controlled trial (RCT) looked at whether motivational text messages could help people give up smoking. It assessed the effect of the messages on smoking habits at six months. Studies with an RCT design compare a treatment against another treatment, a placebo or no treatment. This study compared the quitting rates in a group who received motivational text messages and another who received occasional non-motivational text messages (the control group). An RCT is considered the best type of study to determine the effectiveness of a treatment.
Many RCTs are double blinded. This means that neither participants nor researchers know to which group the participants were allocated. This resolves the problem that knowing which group they belonged to could affect the results, either consciously or unconsciously. However, the nature of the treatment being tested means that this is not always possible. For example, in this study, it would not have been possible to conceal from participants whether they were receiving the intervention or were in the control group. However, this trial was single blinded as the researchers were not told which participants were in which group.
The researchers say that mobile phone technology has the potential to provide personalised stop-smoking support. Motivational messages and methods to change people’s behaviour, which are used in face-to-face stop-smoking services, can be modified for delivery through mobile phones. Content can also be tailored to address the age, sex and ethnic group of each quitter. Given the widespread ownership of mobile phones, they believe that fully automated stop-smoking support can be delivered to large numbers of people at low cost.
The researcher say that although this type of programme has been shown to increase self-reported smoking abstinence at six weeks, the extent to which these early benefits can be maintained in the longer term needs further investigation. They also point out that some previous studies have not used chemical tests to verify whether participants truly stopped smoking, which might give a better indication of quitting rates.
Researchers gathered 11,914 potential participants using advertisements for their trial. To be eligible, participants had to be smokers aged 16 or older who were willing to attempt to quit in the next month and owned a mobile phone. In total, 5,800 volunteers were found to be eligible and entered the trial.
Between 2007 and 2009, they were randomly assigned to either a mobile phone text-messaging stop-smoking programme called txt2stop, or to a control group that received text messages unrelated to quitting. Randomisation was carried out using an independent telephone randomisation system, which also balanced the groups based on their sex, age, educational level and level of nicotine addiction. The system automatically sent the participants motivational or non-motivational texts according to their allocated group. Researchers involved in the trial did not know which participants were allocated to which group, unless the participants told them. All participants were free to take part in other stop-smoking programmes.
People in the group receiving the text-messaging programme were asked to set a quit date within two weeks of being assigned to the group. They received five text messages a day for the first five weeks, and then three a week for the next 26 weeks. These included messages to encourage motivation and behaviour change, encouraging them to persevere with their attempts to quit, such as an introductory message on their chosen quit date: “This is it! … TODAY is the start of being QUIT forever, you can do it!” The text support group could also send a request for a “lapse text” if they smoked, which read: “Don’t feel bad or guilty if you’ve slipped … Slip-ups can be a normal part of the quitting process.”
By texting the word “crave”, quitters could receive instant messages to distract and support them and they could also text each other for support.
The programme was also personalised based on information gathered at the start of the study, sending a selection of texts to address each smoker’s concerns related to quitting, such as potential weight gain. In total, participants had access to a core programme of 186 messages and a further database of 713 personalised messages. Participants in the intervention group were also given top-up vouchers towards phone credit.
Control group participants received short, simple, fortnightly messages relating to the importance of trial participation but not encouraging them to quit. All participants were also offered relevant helpline numbers.
Researchers gathered data from participants on whether they had quit smoking, defined as no more than five cigarettes smoked in the past week at four weeks, and no more than five cigarettes smoked at six months of follow-up. This was done through a website or by telephone. The researchers verified self–reported quitting at six months with a postal saliva test that tested for levels of cotinine, a substance produced in the body as a result of nicotine breakdown, which can be used to distinguish smokers from non-smokers. Those who said they had given up but whose test showed they were still smokers were counted as smokers in the analysis.
The researchers used validated statistical methods to look at the potential effect of the text-messaging programme. They looked at the effects of the intervention by age (split into people over or under 35 years old), level of nicotine addiction, employment status, receipt of a mobile phone top-up voucher and use of other stop-smoking treatments.
The randomisation process allocated 2,915 smokers to the txt2stop intervention and 2,885 to the control group. Eight people were excluded because they were randomised more than once. Results were available for 5,524 (95%) participants.
Researchers found that at six months, 10.7% of those on the txt2stop programme had stopped smoking, compared to 4.9% of those in the control group, with results verified by saliva tests. This equated to a more-than-double rate of quitting for those in the intervention group (relative risk [RR] 2.20, 95% confidence interval [CI] 1.80 to 2.68). The absolute difference was 5.8%, meaning about six extra people in every hundred people offered the motivational texts would stay off cigarettes at six months compared to those not receiving the texts.
Similar results were obtained when participants that were “lost to follow-up” were treated as smokers.
The intervention had similar results in both younger and older smokers and in all socioeconomic groups. Biochemical results showed that more than a quarter of participants who self-reported quitting were smokers. There was no evidence of any difference between the two groups in the use of existing smoking support services.
The researchers say that the txt2stop programme significantly improved stop-smoking rates at six months and should be considered for inclusion in smoking cessation services.
This large study had several strengths, such as using reliable methods for randomisation and ensuring that staff and researchers had no foreknowledge of how treatment was allocated. Results were calculated for both the 95% of participants who completed the study and the full set of participants, counting any participants who were not followed up as smokers. Reports of quitting smoking were verified using saliva tests, which helps increase the accuracy of estimated quitting rates.
However, as with any study, it had some limitations:
Overall, this large, well-conducted trial suggests that text message programmes offering support for stopping smoking could be a valuable addition to smoking cessation services. The researchers plan to publish details of how the content of the test messages might fit into current theories of how to change behaviour, as well as further economic analysis of the cost of the intervention. These are both important questions as the treatment will need to be assessed in relation to existing stop-smoking services.
Analysis by Bazian
Motivational text messages help smokers quit, finds study. The Guardian, June 30 2011
Text messages ‘help smokers quit’. BBC News, June 30 2011
Free C, Knight R, Robertson S et al. Smoking cessation support delivered via mobile phone text messaging (txt2stop): a single-blind, randomised trial. The Lancet, Early Online Publication, 30 June 2011
Written by admin on Thursday, June 30th, 2011 in Swine Flu.
NEW YORK – The swine flu shot appears to be safe for pregnant women, according to a new government report that tallies health problems occurring after the vaccinations.
Written by admin on Wednesday, June 29th, 2011 in Swine Flu.
NEW YORK (Reuters Health) – The swine flu shot appears to be safe for pregnant women, according to a new government report that tallies health problems occurring after the vaccinations.
Written by admin on Wednesday, June 29th, 2011 in Swine Flu.
Doctors have made a “breakthrough in repairing genetic defects”, The Guardian reported.
This news comes after researchers conducted a small trial that tested genetic engineering as a treatment for haemophilia B in mice. In humans, haemophilia B is caused by a genetic fault that interferes with the production of a protein that normally aids blood clotting. In this study, researchers introduced a genetic “toolkit” into living mice to target a faulty gene involved in haemophilia and to replace it with a fully functioning version. The study found that after treatment, the animals’ blood clotted in 44 seconds compared to more than a minute in untreated mice with haemophilia.
This was a small “proof of concept” study and further studies are required to confirm the findings of this exploratory research. The efficiency of this “genetic editing” technique was also limited, with success in only 3–7% of cases.
The early stage of this research means it is not yet clear whether these techniques in animals could eventually be used in humans. There is often a long time between this type of study in animals and the development of a therapeutic cure in humans, but the study provides an important first step towards that goal.
The study was a collaboration between researchers from the Children’s Hospital Philadelphia and other institutions based in Philadelphia and California in the US. The research was funded by the US National Institutes of Health and the Howard Hughes Medical Institute.
The study was published in the peer-reviewed scientific journal Nature.
While The Guardian’s article mainly focused on the potential human implications of the research, its coverage was balanced, clearly stating that the study was in mice and that the technique was inefficient.
This animal study tested whether it was possible to use a gene repair “toolkit” to correct a genetic defect in living mice. The authors state that similar gene repair techniques have been shown to be effective in correcting defects in cells by removing them from an animal, genetically modifying them in a dish in a laboratory, and returning them to the animal. This is not suitable for many diseases, where the affected cells cannot be easily removed from the body and returned. This study developed and tested a method that might be used to correct genetic problems within the body, without the need to remove cells.
The main limitation of this study type is that researchers cannot be certain whether the findings in animals will apply to people. Also, before the technique could be tested in human trials, the researchers will need to ensure that it would be safe enough for use in humans.
This study used a genetically engineered mouse model of the human disease haemophilia B. Haemophilia B is caused by a deficiency in a blood-clotting factor (factor IX) that is normally produced by the liver. The condition is caused by errors, or mutations, in the F9 gene.
Mice were bred to carry the human F9 gene. The version of the gene they carried included a mutation that stops factor IX from being produced, leading to haemophilia B.
The researchers then engineered a genetic toolkit that was designed to cut the mutated F9 gene out of the mouse DNA and introduce a working version of the gene in its place. The toolkit introduced into the mice used enzymes, called zinc finger nucleases (ZFN), that could produce a targeted “cut” in the DNA near the start of the mutated F9 gene. The type of cut produced stimulates the body’s own natural DNA repair mechanisms. A separate part of the genetic toolkit included a template for the normal (non-mutated) version of the human F9 gene, which would allow the cell to produce a fully functioning version of the factor IX protein. This template was designed in such a way as to allow the cell to incorporate this normal version of the F9 gene into the cut region of the DNA during the repair process.
The researchers used a genetically modified virus to deliver their toolkit to the liver cells in order to correct the genetic mutation and allow the liver to produce factor IX normally.
The genetic toolkit was initially introduced into human liver cells grown in the laboratory to see if it functioned as expected. The researchers then injected it into living mice carrying the mutated F9 gene to test how well it specifically targeted the liver cells. They also assessed how much blood-clotting factor was produced as a result of the genetic fix by analysing blood samples and by removing and analysing the mice’s livers. Finally, they compared the time it took for the blood to clot in treated and untreated haemophilic mice.
In two types of laboratory-grown liver cells, the genetic toolkit was successfully able to cut the existing DNA and paste the normal (non-mutated) version of the human F9 gene into the correct region. This process occurred in 17–18% of mutated DNA. When testing the toolkit in mice, the researchers found that 1-3% of the mutated genes in the liver tissue had been repaired by the genetic toolkit.
Overall, they found that their technique produced a 3–7% increase in production of clotting factor IX circulating in the blood of the mice, and that the amount of circulating blood-clotting factor correlated with the level of success in repairing the mutant gene.
After the mice had received treatment, their blood clotted in 44 seconds compared to more than a minute for the mice with untreated haemophilia. However, only five normal mice were compared to 12 treated mice.
The authors reported that their new technique is “sufficient to restore haemostasis (normal blood clotting control) in a mouse model of haemophilia B, thus demonstrating genome editing in an animal model of a disease”. They also reported that the level of genetic editing achieved in this experiment was “clinically meaningful”.
This research demonstrates that a genome-editing technique can be used to correct a genetic defect in living animals, and that this treatment can improve a clinical defect, in this case blood-clotting time in haemophilic mice. This was achieved without the need to remove and genetically manipulate cells, a step that has been necessary when using previously researched techniques.
This study was performed in a small number of mice, so the results will need to be reproduced in more animals to confirm the findings and to improve the efficiency of the technique, which is currently low. It is not yet certain whether these findings in animals can be applied to people. Research will be needed to ensure that such a technique would be safe enough for use in humans before it could be tested for the treatment of human diseases. In addition, research will be needed to determine whether the technique might apply to other genetic conditions, and whether DNA can be cut at the site of other faulty genes and that the technique can target organs other than the liver.
It often a takes a long time for proof of concept research in animals to be developed into a therapy for humans, but this study is an important first step in that process.
Analysis by Bazian
Doctors make breakthrough in repairing genetic defects. June 26 2011
Li H, Haurigot V, Doyon Y et al. In vivo genome editing restores haemostasis in a mouse model of haemophilia. Nature, June 26 2011
Cut-and-paste therapy fixes mouse haemophilia. Nature News, June 26 2011
Written by admin on Wednesday, June 29th, 2011 in Swine Flu.
The risk of feeling run-down and “burnt out” is increased when you work more than 40 hours a week, reports the Daily Mail. The Daily Telegraph adds that simply “having a boring job can leave you just as vulnerable to ‘burnout’”.
The news is based on Spanish research into occupational burnout, a concept that workers can eventually develop a sense of exhaustion, cynicism and inefficiency. It looked at different types of burnout, including underchallenged workers feeling bored and unable to find personal development in their job.
The researchers questioned more than 400 university workers and found that individuals working more than 40 hours a week and working part-time were at greater risk of “frenetic” burnout: feeling involved in their work but with too much to do in the time available. Administration and service personnel were at a higher risk of “underchallenged” burnout than teaching and research staff, as were men compared to women. Employees with more than sixteen years service were at the highest risk of “worn-out” burnout, where a person feels a lack of control or acknowledgement.
Although this research has found associations between a variety of factors and the risk of different burnouts, there are several limitations to this study. For example, it looked at university employees, who are likely to have different roles and working times compared to workers in other sectors. Overall, the research may inform us more about working at the university in question rather than workplaces as a whole.
The study was carried out by researchers from the University of Zaragoza and from other research institutes in Spain. The funding source for this study is not reported. The study was published in the peer-reviewed medical journal, BMC Psychiatry.
This study was generally reported well by the media, although not all reports made it clear that the research only found associations between work habits and burnout. Finding that two factors are associated does not necessarily mean that they have a cause-and-effect relationship.
Different newspapers chose to concentrate on different results: The Daily Telegraph reported that “boring jobs lead to burnout”, while the Daily Mirror, Daily Mail and Metro all had headlines describing the increased risk of burnout with working 40 hours or more each week. The papers also state that the risk of burnout is “six times higher” with working 40 hours or more each week, which could be taken to suggest one cause of burnout.
This was a cross-sectional study carried out on randomly selected employees of the University of Zaragoza in Spain. It was concerned with “burnout”, a type of work-related psychological stress and fatigue that has been the subject of research for more than 35 years. Although there is no single, agreed definition of burnout there is a general consensus among researchers that it is characterised by exhaustion, adoption of a cynical attitude towards work and a loss of efficiency.
In this study, burnout has been classified into three different subtypes: “frenetic”, “underchallenged” and “worn out”. “Frenetic” burnout occurs in subjects who are involved and ambitious, but who overload themselves. “Underchallenged” burnout occurs when subjects are indifferent and bored. “Worn-out” burnout refers to a feeling of lack of control and acknowledgement.
The researchers asked the recruits to complete a questionnaire which collected data on a variety of sociodemographic and occupational factors and assessed burnout. The researchers then used this data to examine the association between different sociodemographic and occupational factors and the different subtypes of burnout syndrome.
This was a cross-sectional study, so the data was examined only at a single point in time rather than following participants over time. As it was cross-sectional, it can only show association between burnout and the examined factors, and cannot show causation, or which among several factors occurred first.
The study sampled 1,600 employees of the University of Zaragoza, with a proportional number of employees drawn from each different class of occupation (classified as teaching and research, administration and service or trainees). An email was sent to the selected participants, explaining the aims of the research and including a link to a questionnaire.
Using the questionnaire, the researchers collected information on a variety of sociodemographic and occupational characteristics, including:
The participants were then asked to complete the “Burnout Clinical Subtype Questionnaire”. In this validated questionnaire, the participants had to indicate the degree to which they agreed or disagreed with statements such as “I have a strong need for important achievements in my work” and “When things at work don’t turn out as well as they should, I stop trying”. Responses were given on a seven-point scale, with higher scores indicating a greater degree of burnout. Scores relating to different sets of statements allowed the researchers to define the extent to which participants represented each burnout subtype.
The researchers then performed a number of analyses of their survey data, grouping the participants in various ways in order to draw associations between results and personal factors. For example, they were divided into three groups based on age:
There is no previously established score for defining burnout in the “Burnout Clinical Subtype Questionnaire”, so the researchers performed analyses comparing high-score groups against low-score groups. They designated the 25% of participants with the highest scores to be the high-score group.
The final sample consisted of 409 participants (a response rate of 25.6%), with participation rates varying across occupation types.
The number of hours worked each week and contract type was associated with “frenetic” burnout – the type seen in subjects who are involved and ambitious, but who overload themselves. Participants working more than 40 hours a week were more likely to have a high score than those working fewer than 35 hours a week (adjusted odds ratio 5.69; 95% confidence interval 2.52-12.82).
In addition, the number of hours worked each week correlated with the risk of burnout, with more hours associated with a greater risk. In an analysis of part-time vs. full-time workers, part-timers were more likely to have a high score, indicating greater burnout symptoms (adjusted odds ratio 3.30; 95% confidence interval 1.12-9.47). While this association was statistically significant, only 25 part-time workers were featured in this particular analysis. Although these participants only worked at the university part-time the researchers say that it is likely that they worked several jobs, which may have increased their risk of burnout.
Being male and working in administration and service were associated with “underchallenged” burnout – the subtype involving feeling indifferent and bored. Administration and service personnel of both genders were more likely to have a high score than teaching and research staff (adjusted odds ratio 2.85; 95% confidence interval 1.16-7.01). Overall, male participants were more likely to have a high score than women (adjusted odds ratio 2.16; 95% confidence interval 1.13-3.55).
Increased length of service was associated with the “worn-out” burnout type. Participants in the group who had been working for 4-16 years were more likely to have a high score (adjusted odds ratio 3.44; 95% confidence interval 1.34-8.86), as were those who had been working for more than 16 years (adjusted odds ratio 4.56; 95% confidence interval 1.47-14.16). As the length of service increased, likelihood of a high score also increased. Being in a stable relationship, having children and being educated reduced the risk of this type of burnout. Participants not in a stable relationship were more likely to have a high score (adjusted odds ratio 1.91; 95% confidence interval 1.05-3.45), as were those without children (adjusted odds ratio 1.90, 95% confidence interval 1.09-3.31). Having a university education decreased the likelihood of a high score when compared to being educated up to secondary level (adjusted odds ratio 0.48, 95% confidence interval 0.24-0.96).
The researchers conclude that their results “support the idea of a differential characterisation of burnout syndrome by providing specific associations with a number of sociodemographic and occupational factors”.
Conclusion
The researchers have identified associations between the different burnout subtypes and different sociodemographic and occupational variables. However, there are several issues that need consideration when interpreting the results.
Principally, there are issues relating to the selection and recruitment of participants, which may have influenced the results. Recruitment was conducted using an email explaining that the purpose of the research was to study the presence of burnout in the workplace, which may have unduly influenced the responses the participants gave when they later completed the study’s online questionnaire (which similarly had the word “burnout” in the title).
Also, there was only a 25.6% response rate, and an uneven response between each occupational groups. The authors say these values are comparable to other studies using similar data collection procedures, but it is possible that those who responded to the invitation were different in some way from those who did not respond. For example, worker satisfaction levels might have influenced the decision to complete the questionnaire, leading to a disproportionate number of happy or unhappy workers responding.
Other points to consider include:
Boring jobs lead to burn-out. The Daily Telegraph, June 28 2011
Working 40 hours or more a week raises burnout risk. Daily Mirror, June 28 2011
Working more than 40 hours per week increases ‘burnout’ risk. Daily Mail, June 28 2011
‘Burnout risk’ six times higher if you work more than 40 hours a week. Metro, June 28 2011
Montero-Marín J, García-Campayo J, Fajó-Pascual M et al. Sociodemographic and occupational risk factors associated with the development of different burnout types: the cross-sectional University of Zaragoza study. BMC Psychiatry 2011, 11:49
Written by admin on Wednesday, June 29th, 2011 in Swine Flu.
Two people in Mumbai tested positive for the H1N1 virus on Tuesday. After throat swabs were sent to Haffkine institute, pathological tests conducted on the samples diagnosed that the swine flu virus had infected a 37-year-old woman from Chandivli and a three-year-old girl.
Written by admin on Tuesday, June 28th, 2011 in Swine Flu.
“Women who spend just three hours a day in the sunshine can halve their risk of developing breast cancer,” reported the Daily Express. It said that a study has shown the benefits of vitamin D and that “exposure to sunlight for 21 hours a week between April and October significantly cuts the chances of developing a tumour”.
The news report was based on a study carried out in Ontario, Canada. The study compared the amount of time spent outdoors during four life periods – teens, 20s and 30s, 40s and 50s and 60–75 years old – in women who developed breast cancer and women of a similar age who did not.
The researchers compared the risk of breast cancer in women who spent less than 6 hours outside a week, with women who spent over 21 hours outside in each stage of life, and found that the women who spent longer outside had between 26% and 50% lower odds of breast cancer.
This was a relatively large study, but it had several limitations related to its design. The average age of the women was 56 and they had to recall the amount of time they had spent out of doors over most of their lives, which increases the likelihood of error. In addition, vitamin D levels were not measured but estimated. Further research would need to establish whether vitamin D levels are associated with the effects observed.
The study was carried out by researchers from Cancer Care Ontario. Funding was provided by the Canadian Breast Cancer Research Alliance. The study was published in the peer-reviewed Journal of American Epidemiology.
Both the Daily Mail and the Daily Express did not make it clear that the study looked at relative odds of breast cancer rather than absolute risk, which may lead people to misinterpret the results. Additionally, the study did not measure vitamin D directly, so it is not possible to say that vitamin D is responsible for the effects seen, as the newspapers suggest. Other factors may have influenced the risk of breast cancer.
This study investigated whether there was an association between vitamin D production from exposure to sunlight and breast cancer risk. The researchers said that recent studies have suggested that vitamin D may be associated with reduced risk of breast cancer, but that these studies have only looked at dietary vitamin D levels.
In this population-based case-control study, the researchers wanted to see whether there was an association between breast cancer risk and time spent outdoors, ultraviolet radiation levels where the person lived, skin colour and sun-protection practices.
The researchers used data from the Ontario Women’s Diet and Health Study. In this study, the Ontario Breast Cancer Registry was used to identify women who were 25–74 years old who developed breast cancer in 2002 and 2003. The researchers contacted 4,109 of these women, and 3,101 of them took part in the study in 2003 and 2004. As a control group, women of a similar age who did not have breast cancer were randomly selected from households in Ontario, and 3,420 of them completed the study.
The women were asked to complete a questionnaire about risk factors for breast cancer and to complete a food-frequency questionnaire to record their dietary habits. The researchers used questions on ethnicity or racial background as a substitute for skin colour. Ninety percent of the study participants were Caucasian, so skin colour was classified as Caucasian or non-Caucasian (6% were Southeast or South Asian, 2% black, 1% aboriginal, and less than 2% had other skin colours).
The participants were asked about variables related to sun exposure during four periods of their lives: teenage years, 20s and 30s, 40s and 50s and 60–75 years old. Women were asked how much time they spent outdoors each weekend or week day, what sun protection (such as sunscreen or wearing long sleeves) they used and where they lived (the latitude and longitude was used to estimate how much UV light the participants’ were exposed to). The researchers said that between November and March, the sun in Ontario is not sufficient to produce vitamin D. As such, they only looked at sun-exposure frequency from May to September.
Each woman was given a solar vitamin D score for each of her four periods of life. This score took into account hours of ultraviolet exposure per week, skin colour and sun protection practices.
In their statistical analysis, the researchers used a technique called logistic regression to calculate how much the solar vitamin D score was associated with risk of cancer at each age period. They also gave people a cumulative life score, by classifying sun exposure as high (greater than average) or low (less than average) and combining all the periods.
The researchers identified several factors other than sun exposure that could be associated with breast cancer risk and could potentially influence the researchers’ calculation of how much the vitamin D score predicted breast cancer risk (confounders). These were: the women’s marital status, education, ethnicity, body mass index, smoking status, amount smoked, breastfeeding, lactation, age of first period, oral contraceptive use and duration of use, whether the women had given birth and their age at childbirth, age of menopause, hormone replacement therapy use, family history of breast cancer or a history of non-cancerous breast disease, screening mammogram uptake, alcoholic drinks, dietary fat and calorie intake, physical activity and the amount of vitamin D and calcium they acquired from food and supplements.
The average age of the women in the study was 56 years old. Most women were postmenopausal (68% of cases and 64% of controls).
The researchers compared the chances of having cancer between the women who spent the most time outdoors (more than 21 hours a week) and those who spent the least time outdoors (less than six hours).
These results were not adjusted for confounders.
The researchers then looked at the risks associated with solar vitamin D score. They compared women with solar vitamin D scores that were in the top 25% with women whose scores were in the lowest 25%. These calculations were also adjusted for age.
The results showed that:
The researchers said that time spent outdoors during multiple periods of life and their proxy measure of vitamin D from sun exposure were associated with a reduced risk of breast cancer. They said: “it is plausible that vitamin D production mediates the inverse association observed between sunlight exposure and breast cancer risk, yet future studies are needed to confirm this risk."
This was a relatively large population-based case-control study. The findings indicated that women who spent a lot of time outdoors had a lower risk of breast cancer than those who spent very short periods of time outdoors.
The large size of this study is a strength, but the study also had several limitations, which affect how it could be interpreted for the UK population:
This type of study can identify possible factors that may be associated with the risk of disease. However, the study’s limitations, particularly its reliance on the women to recall their sunlight exposure, means that further research will be needed to see whether exposure to sunlight affects breast cancer risk.
Sunlight stops breast cancer. Daily Express, June 28 2011
Three hours in the sun a day ‘can halve breast cancer risk’. Daily Mail, June 28 2011
Anderson LN, Cotterchio M, Kirsh VA and Knight JA. Ultraviolet Sunlight Exposure During Adolescence and Adulthood and Breast Cancer Risk: A Population-based Case-Control Study Among Ontario Women. American Journal of Epidemiology 2011, First published online: June 9
Written by admin on Tuesday, June 28th, 2011 in Swine Flu.
Scientists have found a “missing link” in the treatment of multiple sclerosis (MS), the Daily Mirror has reported. The newspaper said that new research has identified a new molecule “that could lead to a drug treatment to repair the damage caused by the disease”.
The study used human brain tissue and mice to explore the function of cells called oligodendrocytes. These cells make myelin sheaths, the fatty structures that surround nerve cells and help them send their signals more effectively. Damage or loss of these sheaths, which happens in multiple sclerosis, hampers the ability of the brain to send signals correctly, and leads to symptoms such as difficulty controlling the body’s movement.
In their experiments, the researchers identified that a protein, called Axin2, plays an important role in the development of myelin-making cells. They also identified a chemical that can stabilise levels of Axin2 and accelerate the repair of damaged myelin sheaths in mice.
More animal research will now be needed to determine whether the chemical used in this study, or similar chemicals, appear to be effective and safe enough for tests in humans. Such research takes time, and not all chemicals that initially show promise are effective or safe in humans. However, the finding offers a new avenue of exploration for potential treatments for diseases such as MS.
The study was carried out by researchers from the University of California, Stanford University and the University of Cambridge. It was funded by the US National Multiple Sclerosis Society, the UK Multiple Sclerosis Society, the US National Institutes of Health and the University of California.
The study was published in the peer-reviewed scientific journal Nature Neuroscience.
In its report, the Daily Mirror did not state that the research took place in the laboratory and animals, but it did note that any new treatments for MS might be another 10 to 15 years away.
This laboratory and animal study looked at the role of a protein called Axin2 in the development of the myelin sheath, a protective membrane wrapped around some nerve cells.
Myelin sheaths are layers of a fatty substance that wrap around the axons, the long structures that nerve cells use to transmit their signals to each other and other tissues. The sheaths “insulate” the nerves, and help them to transmit signals more quickly. These sheaths and the axons they protect make up the white matter of the brain, while the bodies of the nerve cells make up the grey matter. The myelin sheaths are made by specialised cells called oligodendrocytes.
Damage to the myelin sheaths plays an important role in a number of conditions. For example, if the white matter is damaged during foetal development (as might occur if the brain is starved of oxygen), it can lead to a complex group of movement and co-ordination disorders which fall under the broad term of cerebral palsy. In multiple sclerosis, the body’s immune system attacks the myelin-producing oligodendrocytes, causing loss of the myelin sheaths and neurological symptoms.
If they are damaged, the myelin sheaths can be regenerated by oligodendrocyte progenitor cells (OPCs). However, in damaged white matter, some OPCs appear to “stall” in their development, and fail to progress to the myelin-making stage. This study investigated the Axin2 protein, which the researchers thought might influence the development of OPCs into oligodendrocytes.
First, the researchers looked at whether the human gene that produces Axin2 (called AXIN2) was active in OPCs in damaged brain tissue. They compared this to the activity in undamaged brain tissue from human newborns, which provided a control group. They also looked at whether AXIN2 was active in human active multiple sclerosis lesions (areas of white matter damage where there is ongoing inflammation).
The researchers genetically engineered mice in a way that allowed them to identify cells in which the AXIN2 gene was active during development. They also genetically engineered mice to lack the AXIN2 gene in order to determine what effect this had on oligodendrocytes. They then treated these mice and normal mice with a chemical that kills oligodendrocytes, and compared the response of their OPCs.
Finally, they tested the effects of a chemical called XAV939, which they thought might stabilise levels of the Axin2 protein. They tested whether it had this effect on OPC cells in the laboratory. They then tested what effect it had on slices of mouse brain which had been starved of oxygen or exposed to a chemical that reduces myelination of the nerves. Mice whose spinal cords had been damaged with the demyelinating chemical were treated with XAV939, and the researchers looked at the effects.
The researchers found that the AXIN2 gene was active in the oligodendrocyte progenitor cells (OPCs) in damaged newborn brain tissue, but not undamaged newborn brain tissue. They also found that the AXIN2 gene was active in the OPCs in active multiple sclerosis lesions, but not in white matter that appeared normal.
In mice, they found that the AXIN2 gene was active in immature OPCs, but not fully mature oligodendrocytes. They also found that mice lacking the AXIN2 gene had slower development of the OPCs. Normal adult mice treated with a chemical that kills oligodendrocytes showed new OPCs with active AXIN2 in the damaged area by ten days after the injury. When this experiment was repeated in mice lacking AXIN2, the oligodendrocyte cells regenerated after the injury but remyelination was delayed compared to normal mice.
The researchers found that the chemical XAV939 stabilised levels of Axin2 in OPCs in the laboratory. Slices of mouse brain in the laboratory, which had been starved of oxygen or exposed to a demyelinating chemical, showed reduced levels of myelin. Treating these slices of brain with XAV939 reversed this effect.
In mice whose spinal cords had been treated with a demyelinating chemical, XAV939 increased the number of oligodendrocytes in the injured areas. It did this by increasing the rate at which OPCs developed into mature oligodendrocytes and were able to remyelinate the nerves.
The researchers concluded that the AXIN2 gene is “an essential regulator of remyelination”. They also said that it could serve as a target for drugs and could be manipulated to accelerate this process.
This research used several techniques to explore how a protein called Axin2 is involved in the development of oligodendrocyte cells from oligodendrocyte progenitor cells. Oligodendrocytes produce myelin sheaths that surround nerve cells and help them transmit their signals more effectively. The study also found that a chemical called XAV939 can accelerate the repair of damaged myelin sheaths in mice with spinal cord lesions.
This type of animal and cellular research is crucial for understanding the biology of disease, and can identify chemicals that may be worth testing in humans. More animal research will be needed to determine whether the chemical used in this study or similar chemicals appear to be effective and safe enough for testing in human trials. Such research takes time, and not all chemicals that show promise in animals are effective or safe in humans. However, the finding offers a new avenue of exploration for potential treatments for diseases such as MS.
Analysis by Bazian.
Scientists make important MS find. Daily Mirror, June 27 2011
Fancy SPJ, Harrington EP, Yuen TJ et al. Axin2 as regulatory and therapeutic target in newborn brain injury and remyelination. Nature Neuroscience, 2011.