"Scientists have found a way of preventing the spread of cancer from the site of the original tumour," The Independent reports. Targeting proteins called DNA-PKcs could prevent cancer cells moving to other parts of the body. This is known as metastatic cancer and is often fatal.
The research involved mice as well as tissue samples from more than 200 prostate cancer patients. Researchers found mice treated with an inhibitor to block DNA-PKcs had reduced cancer spread compared with mice that were not treated.
Patients whose prostate cancer tissue samples showed higher DNA-PKcs levels were more likely to have had cancer progression (metastasis). As yet we do not know if a DNA-PKcs inhibitor would have the same outcome in humans as it did in mice.
This research furthers our knowledge about the biology of cancer progression and has identified another possible way to tackle the spread of cancer. Further investigation in humans would be required to confirm whether these findings are of use for improving outcomes for prostate cancer patients.Where did the story come from?
The study was carried out by researchers from Thomas Jefferson University, the University of Michigan, Cleveland Clinic, the University of California, Los Angeles (UCLA), the Mayo Clinic, Columbia University Medical Centre, and GenomeDx Biosciences.
It was funded by the Prostate Cancer Foundation (PCF), PCF/Movember and Evans Foundation, PA CURE, the US Department of Defense, UCLA, the National Cancer Institute, and the National Institutes of Health.
The study was published in the peer-reviewed journal Cancer Cell.
This research has been reported in the media as a breakthrough – the Daily Express goes as far as talking about a possible "cure". However, while certainly promising, the research is at an early stage. Crucially, we do not know whether these findings will result in new treatments in humans.What kind of research was this?
This laboratory and animal study in mice looked at whether the protein DNA-PKcs is linked to cancer progression. This type of animal study is used to understand the biology of human disease better.
While there are a lot of similarities in the biology of different species, there are some key differences. This means that while results do give an indication of what is likely to happen in humans, we cannot be certain that any findings would be exactly the same.
Researchers looked at some prostate cancer tissue samples to see if their findings looked like they might apply to people, but the human research is at an early stage.What did the research involve?
The researchers first studied DNA-PKcs in cells in the lab to look at what it does in the cell. It was believed to aid the spread of cancer cells.
They then used mice injected with human prostate cancer cells to investigate whether it is possible to stop cancer spread by targeting the DNA-PKcs protein.
Mice were either treated with an inhibitor that blocks the DNA-PKcs protein or an inactive control treatment. The size of their tumours was monitored by live imaging.
After 31 days three mice were selected from the control arm and switched to receive the DNA-PKcs inhibitor to investigate the impact. Three mice were also selected from the protein inhibitor group and stopped receiving this treatment.
The researchers went on to analyse cancer tissue samples from 232 patients with prostate cancer, and measured the amount of DNA-PKcs the cells contained. The researchers looked at how their DNA-PKcs levels related to their outcomes.What were the basic results?
The laboratory tests showed the DNA-PKcs protein was involved in controlling the activity of genes cancer cells need to move and spread. The researchers also found blocking DNA-PKcs reduced the spread of cancer in mice.
Mice who crossed over from the control arm to the protein inhibitor did not show a reduction in tumour size. This implies the DNA-PKcs inhibitor blocked the spread of cancer rather than suppressing tumour growth.
When mice stopped receiving the DNA-PKcs inhibitor, their cancer spread. Mice who stayed on the DNA-PKcs inhibitor and did not cross over were found to have less cancer spread than those who stayed in the control arm.
The patient samples showed men with higher DNA-PKcs levels were more likely to have had prostate cancer progression and to have died.How did the researchers interpret the results?
The researchers concluded they have identified DNA-PKcs as a protein that drives prostate cancer progression and spread.
Higher levels of DNA-PKcs in prostate cancer tissue were an independent predictor of metastasis, recurrence and poor survival. Researchers hope this discovery will pave the way for new drug treatments.Conclusion
This lab study in mice found a protein called DNA-PKcs is involved in the spread of cancer cells, and assessed whether it is possible to stop this spread by targeting the protein.
It demonstrated that mice with human prostate cancer cells treated with an inhibitor to block the protein had reduced cancer spread compared with those who were not treated.
Analysis of patient prostate cancer samples showed higher DNA-PKcs levels were linked to a greater risk of cancer progression. This suggests the protein may be playing a similar role in humans, and researchers will want to go on to see if DNA-PKcs inhibitors could be used as a new treatment to stop the spread of cancer.
This protein is involved in the spread of cancer but does not appear to be involved in cancer growth, so any new drugs blocking it would also need to be used alongside other drugs. It's also not yet clear whether the findings only apply to prostate cancer cells.
While this research seems to show promise, the findings on the DNA-PKcs inhibitors were in mice and therefore may not be applicable to humans. Headlines reporting this as a cancer "breakthrough" should be taken with caution.
Researchers will need to determine whether these inhibitors seem safe and effective enough in animals before they could be tested in humans. Once this is done, a randomised trial in humans would be required before we know its effects.
Links To The Headlines
Scientists discover way of targeting 'lynchpin' molecule to prevent the spread of cancer. The Independent, July 13 2015
New drug to beat cancer: Breakthrough as scientists find key to stopping disease. Daily Express, July 14 2015
Links To Science
Goodwin JF, Kothari V, Drake JM, et al. DNA-PKcs-Mediated Transcriptional Regulation Drives Prostate Cancer Progression and Metastasis (PDF, 4.43Mb). Cancer Cell. Published online July 13 2015
The family of a British backpacker who died after drinking gin which had been mixed with methanol have launched a campaign to warn travellers of the dangers of fake alcohol.
Cheznye Emmons, 23, was fatally poisoned after drinking the counterfeit gin, which she bought from a shop in a sealed bottle sporting a familiar brand while travelling in Indonesia in 2013.
Methanol (also known as methyl alcohol) is a colourless liquid with a mild alcohol odour. When ingested, it is extremely poisonous and is known to cause blindness, kidney failure, seizures and death.
The chemical is deliberately added to strengthen or stretch illegal alcoholic drinks, especially spirits, some of which are being sold in bars, shops and hotels in popular tourist areas such as Bali, Lombok and Sumatra.Bottles 'look genuine'
The practise is common in many parts of the world. However, Indonesia has recently been singled out following a number of deaths and cases of serious illness of locals and foreigners.
Some fake alcohol on sale in Indonesia has been found to contain concentrations of methanol 44,000 times above safe levels.
Figures suggest 280 people have died from illicit alcohol poisoning since 2011 in Indonesia. Three Brits have died from methanol poisoning in the country in the last five years.
The Foreign and Commonwealth Office (FCO) advises tourists to “take extreme care when purchasing spirit-based drinks, as bottles may appear to be genuine when they are not.”
The FCO reports that there have also been cases of methanol poisoning from drinking adulterated “arak” or “arrack” - a local rice or palm liquor.‘Save a Life’ campaign
The Emmons family set up the Save a Life Campaign soon after Cheznye's death and have created a poster for GP surgeries warning people travelling to Indonesia, including Bali, of the dangers of counterfeit alcohol.
Measha Emmons, Cheznye's sister, says: "The bottle may be sealed and it may look genuine but it may still have been contaminated with methanol. You won't be able to taste the difference.”
Cheznye, who was travelling with her boyfriend, first showed signs of methanol poisoning when she woke up a day after drinking the fake gin unable to see. She died five days later in hospital.Signs of methanol poisoning
The first signs of methanol poisoning include drowsiness, feeling unsteady and loss of inhibition, but these are often confused with the effects of drinking alcohol and may not be noticed.
It can be several hours before the major symptoms of methanol poisoning appear including:
- abdominal pain
- feeling breathless
- impaired vision and, in severe cases, blindness
Without prompt treatment, the poison will continue to build up and can lead to coma, convulsions and death. Patients who survive may suffer permanent visual impairment.
Methanol poisoning can be treated by giving the patient fomepizole or ethanol through an intravenous drip to try to reduce the level of poisoning and dialysis to remove toxic substances from the kidneys.Tips on staying safe
Here's a checklist to help you reduce your risk of methanol poisoning:
- Don't buy illegal alcoholic drinks.
- If the price of your alcoholic drink looks too good to be true, it probably is.
- Buy alcoholic drinks from a reputable vendor and check bottle seals are intact.
- Be suspicious of alcoholic drinks offered for sale in informal settings that are not licensed to sell alcohol, such as market stalls.
- Steer clear of alcoholic drinks sold in unlabelled containers .
- Check branded products for labels that are poorly printed or with errors, or bottles with broken seals. Do not buy these.
- Be aware of the signs of methanol poisoning and seek medical attention immediately if you suspect you or a companion have ingested methanol.
"Is the elixir of life as simple as two cups of tea?," the Mail Online asks, prompted by a study looking at whether tea drinking is associated with a longer life expectancy in women.
This study included more than a thousand older women with an average age of 80. The women completed food and drink questionnaires, and the data from this was put into special databases to estimate their flavonoid intake.
Flavonoids are plant compounds found in various foods and drinks, including tea, chocolate and wine. They are said to have an antioxidant effect by helping prevent cell damage.
The researchers looked at how flavonoid intake was linked to the women's risk of death from any cause over the next five years.
They found those with the highest intake had a reduced risk of death compared with those with the lowest. In this group of older women, black tea contributed the most to total flavonoid intake.
However, although the study did find a link, this does not prove that tea or flavonoids are the single direct cause of reduced mortality. Various unmeasured health and lifestyle factors (confounders) could have influenced the results.
There are also possible inaccuracies in the estimation of flavonoid intake, and the results of this older group of Australian women cannot be applied to everyone.
Overall, this study does add to the body of research assessing flavonoids, but provides no proof that the compound – or tea specifically – reduces mortality in older women.
Where did the story come from?
The study was carried out by researchers from the University of Western Australia.
It was funded by Kidney Health Australia, Healthway Health Promotion Foundation of Western Australia, Sir Charles Gairdner Hospital Research Advisory Committee, and project grants from the National Health and Medical Research Council of Australia.
It was published in the peer-reviewed American Journal of Clinical Nutrition.
The Mail Online's coverage hailing tea the "elixir of life" has not taken into account the important limitations of this research.What kind of research was this?
This prospective cohort study followed a group of older women over the course of five years to explore any links between flavonoid intake and overall mortality.
Flavonoids are plant compounds thought to have various potential health benefits, including effects on the cardiovascular system and glucose metabolism. Particularly rich sources include tea, chocolate, fruit and red wine.
Though previous research has investigated the link between flavonoids and particular health outcomes such as cardiovascular disease and cancer, there is said to have been little research investigating all-cause mortality.
Cohort studies such as this can demonstrate associations but cannot prove cause and effect, as other factors could be involved.What did the research involve?
This study included 1,136 postmenopausal women (aged over 75) taking part in the Calcium Intake Fracture Outcome Age Related Extension Study that started in 2003. This was an extension of a randomised controlled trial of calcium supplements to prevent fractures.
The study included 1,063 women who completed food questionnaires in 2003. These questionnaires included questions on average tea and coffee consumption over the past 12 months.
The study then followed up all-cause mortality over the following five years to 2008, linking the women to database registries. These recorded cardiovascular and cancer events using valid medical codes, and deaths were also identified in the mortality register.
The researchers used two different databases on the flavonoid composition of different foods and drinks so they could estimate flavonoid intake.
They then looked at the link between all-cause mortality and flavonoid intake. They took into account potential confounders recorded at the start of the study.
These included existing cardiovascular disease and cancer recorded in the registries, age, body mass index (BMI), self-reported smoking status, alcohol consumption, fruit and vegetable intake, and physical activity.What were the basic results?
Over the five years of follow-up, there were 129 deaths (12% of women). Average daily flavonoid intake was 674-696mg a day, depending on which of the two databases was used to estimate flavonoids.
Higher flavonoid intake was associated with a reduced risk of all-cause mortality. Compared with women with the lowest intake (less than 525 or 547mg a day), those with the highest intake (above 788 or 813mg a day) had a 62-64% significantly reduced risk of mortality – again, depending on which database was used to estimate flavonoids.
The researchers found similar results when looking specifically by cause of death, whether cardiovascular or cancer.
When the researchers looked specifically at flavonoids, black tea appeared to be the major dietary contributor. Tea accounted for between 59% and 82% of the total flavonoid intake.How did the researchers interpret the results?
The researchers said that, "Using the most comprehensive flavonoid databases, we provide evidence that high consumption of flavonoids is associated with reduced risk of mortality in older women. The benefits of flavonoids may extend to the [disease cause] of cancer and cardiovascular disease."Conclusion
Flavonoid plant compounds have been researched extensively, with studies exploring their possible health benefits.
In this research, there is an association between higher flavonoid intake and a reduced risk of death from any cause over five years in a cohort of older women.
However, this study provides no proof that drinking tea will help you live longer. There are several important points to bear in mind:
- The design of this study cannot prove cause and effect. Though it has adjusted for various potential health and lifestyle confounders, it is unlikely to have taken all of them into account. It is therefore not possible to say that flavonoids are the single direct cause of reduced mortality.
- This is a very specific population group: postmenopausal women with an average age of 80 who were recruited to a trial investigating calcium supplements to prevent fractures. They therefore may not be representative of all older women – for example, the women in this trial were of quite high socioeconomic status. Their results can certainly not be applied to women as a whole, or men.
- Foods and drinks were assessed by food frequency questionnaire. Although these may be validated ways of assessing intake, they are still subject to inaccuracy. For example, people may not be able to give a reliable indication of their tea consumption over the past year.
- This information on foods and drinks was put into two different databases to estimate flavonoid intake. As the results showed, the total intake amounts, or the risk reductions, varied depending on which of the two databases were used. This means these may not be completely accurate estimates of flavonoid intake.
- The media linked these findings to tea, as black tea was the major source of flavonoids, though the main risk analyses were not solely based on flavonoid intake from tea. The researchers say an intake of about 350mg is equivalent to approximately two cups of tea, so the highest intakes of 788 or 813mg a day would be equivalent to more than four cups of tea.
Overall, this study adds to the body of research assessing the benefits of flavonoids, but provides no proof that they – or tea specifically – reduce mortality in older women.
Read more about health advice for women aged 60 and above.
Links To The Headlines
Drinking daily cups of tea makes women live longer, a new study finds. Metro. July 11 2015
Links To Science
Levy KL, Hodgson JM, Croft KD, et al. Flavonoid intake and all-cause mortality. The American Journal of Clinical Nutrition. Published online April 1 2015
"Third of overweight teenagers think they are right size, study shows," The Guardian says in one of many headlines on widely covered UK research.
The research, which looked into English 13-15-year-olds' understanding of their own weight, led the Mail Online to refer unkindly to "generation fat-blind".
The large study demonstrated that while most normal-weight adolescents correctly see themselves as about the right weight, a large number of overweight or obese adolescents wrongly thought they were about the right weight or too light.
Parents probably ought to refrain from a "told you so" attitude to this news, as so-called fat shaming is not considered a great way to help anyone lose weight.
Helping a teen to understand that familiar media images of overweight and obese people don't necessarily give the full picture, and that addressing the problem can improve the quality and length of their life, may be more successful.
The findings may also help policymakers work out how best to target health promotion messages at this important age group and help them potentially make changes for the rest of their lives.Where did the story come from?
This study was accurately reported by a number of media sources, with a good explanation of its key findings and the risks associated with obesity.
However, there was a general lack of information about the limitations of this study. The Mail's headline use of the term "fat-blind" may be seen as pejorative and misleading, especially when we do not necessarily understand all the reasons for the research findings.What kind of research was this?
This study analysed data from the Health Survey for England looking at adolescents' perception of their weight.
Looking at this data is a good way to understand adolescents' weight perceptions because measurements were taken professionally and weight perception questions were self-reported in the survey.
However, this type of study can have chunks of missing data, particularly where people declined to be weighed, which may have biased the results.What did the research involve?
The researchers used data for 4,979 teens aged 13 to 15. The data was taken from the results of the Health Survey for England between 2005 and 2012.
This annual survey presents a representative sample of the general population of England. It surveys adults and up to two children under 16 (selected at random in families with three or more eligible children).
Researchers weighed and measured the teens at home, and then calculated their body mass index (BMI). Weight status was defined according to the International Obesity Taskforce criteria, which classifies BMI values according to age and sex as:
- thin (underweight)
- normal weight
The 13-15-year-olds were also asked: "Given your age and height, would you say that you are about the right weight, too heavy, or too light?".
The researchers also included age, sex, ethnicity and the socioeconomic status of the teens in their analyses.What were the basic results?
The data showed nearly three-quarters (73%) of adolescents in the study had a BMI placing them in the normal weight range, but 20% were overweight and 7% were obese.
Normal-weight adolescents generally felt they were the correct weight (83%), with just 7% who thought they were too heavy, while 10% thought they were too light.
More girls (11%) considered themselves too heavy than boys (4%). Girls (6%) were also less likely to consider themselves too light than boys (13%).
Overestimation was more likely among those on the heavier end of the normal-weight group (10%) than the lighter end (2%).
About 60% of the overweight/obese group felt they were too heavy, 39% thought they were about the right weight, and 0.4% felt they were too light.
Again, girls (68%) who were overweight or obese were more likely to think so than boys (53%).
Girls (32%) were also less likely than boys (47%) to think they were the right weight or too light. Overweight adolescents were much more likely to underestimate their weight (52%) than those who were obese (7%).
The researchers excluded adolescents who were underweight from the analysis as this group consisted of 248 people, which they say was too small to calculate meaningful results.How did the researchers interpret the results?
The researchers concluded that, "Overestimation of body weight among normal-weight adolescents is relatively uncommon; potentially a cause for celebration.
"However, almost half of boys and a third of girls with a BMI placing them in the overweight or obese BMI range perceived themselves to be about the right weight.
"Lack of awareness of excess weight among overweight and obese adolescents could be cause for concern."Conclusion
This study aimed to see whether UK teenagers' perception of their weight matched up with reality. It demonstrated that most normal-weight adolescents correctly see themselves as about the right weight and they overestimated their weight fairly rarely.
But a large proportion of overweight and obese adolescents thought they were about the right weight or even too light.
This study had a large population size, and analyses were weighted to match key population characteristics.
However, the weight measurements were not available for all adolescents in the survey – this may have represented those who were more concerned about their weight and declined measurement, leading to biased results.
Also, overweight and obese adolescents may not have completed the questionnaires truthfully through embarrassment or fear of the consequences.
Only people aged 13 to 15 were analysed, so further research would need to be carried out in other age groups to target issues associated with weight perception if necessary.
Overweight and underweight teens are a concern to both their parents and society. They are likely to grow into overweight or underweight adults, particularly if they do not see that they are not a healthy weight.
The reasons teenagers don't see themselves as overweight may include the commonly seen images of severely obese individuals in the media used to represent stories about weight issues. These could lead to the impression that only those who have a visibly very high body weight are overweight or obese.
Excess weight can lead to a range of other health concerns, including an increased risk of type two diabetes and certain cancers.
Even if teenagers aren't interested in these long-term health messages, it's vital to find ways to improve their understanding of the implications of their weight. And if they understand, it's vital we're able to give them simple advice on achieving a healthy weight in a way that doesn't make them feel patronised.
Links To The Headlines
Third of overweight teenagers think they are right size, study shows. The Guardian, July 9 2015
Overweight teens 'do not see themselves as too heavy'. BBC News, July 9 2015
Links To Science
Jackson SE, et al. Weight perceptions in a population sample of English adolescents: cause for celebration or concern? International Journal of Obesity. Published July 9 2015
"The danger of an online diagnosis: Millions of emergencies are MISSED through symptom checker websites," the Mail Online reports. American researchers have assessed the accuracy and reliability of 23 symptom checkers, including the NHS Choices symptom checker.
The researchers were looking at both accuracy of diagnosis and triage. Triage is the process of determining the severity of a condition.
They did this by using a series of symptoms and medical history known to be associated with specific conditions. These types of combination are known as clinical vignettes.
The NHS Choices symptom checker doesn’t offer a diagnosis – it only provides triage advice.
Researchers found that the NHS Choices symptom checker correctly identified emergency and urgent conditions in 87% of cases. But it also incorrectly triaged non-emergency or non-urgent conditions in 80% of cases, which theoretically would result in an unneeded visit to A&E or a call for an ambulance.
While symptom checkers are far from perfect, they are better than just leaving people "Googling" their symptoms, which is estimated to have a 64% success rate in identifying emergency and urgent cases.
Where did the story come from?
The study was carried out by researchers from Harvard Medical School, Brigham and Women’s Hospital, Boston Children’s Hospital and Beth Israel Deaconess Medical Center, all in Boston. It was funded by the US National Institutes of Health.
Researchers involved in this study say they have not been, nor plan to be, involved in the development, evaluation, promotion, or any facet of a Harvard Medical School-related symptom checker and they had no support from any organisation for the submitted work. This includes no financial relationships with any organisations that might have an interest in the submitted work in the previous three years, or other relationships or activities that could appear to have influenced the submitted work.
In the interests of transparency, we should also point out the Behind the Headlines editorial team is employed by the Health & Social Care Information Centre, which is the same NHS organisation that runs the NHS Choices symptom checker.
The study was published in the peer-reviewed British Medical Journal on an open-access basis, so the study is free to read online or download as a PDF.
It was reported by the Mail Online website in the UK. Overall, the Mail reported the story accurately, but the limitations of the study were not fully explained. Its headline "Millions of emergencies are MISSED through symptom checker websites, study warns" is untrue. The study provides no estimate of how many emergency cases were misdiagnosed by symptom checkers around the world.
What kind of research was this?
This was an audit study that aimed to assess the diagnostic and triage accuracy of online symptom checkers (tools that use computer algorithms to help patients with self-diagnosis or self-triage). Triage is the process of determining the priority of patients' treatments, based on the severity of their condition.
With improvements in technology and access to the internet, people are increasingly using the internet to research their health concerns. For example, researchers quote that the NHS Choices website has over 15 million visits per month. That figure was actually based on 2012 data; the figure for 2015 averages around 50 million visits a month.
Although there are many advantages to using symptom checkers, such as providing out-of-hours advice and reducing the burden on GP and A&E departments, they cannot always take the place of face-to-face clinical assessment.
What did the research involve?
Researchers searched for online symptom checkers that were in English, free to access, publicly available, and did not focus on a single type of condition.They used terms like "symptom checker" or "medical diagnosis" to find symptom checkers in Google and Google Scholar, and also searched for any relevant apps in the Apple app store and Google Play.
After searching and sifting, they finally included 23 online symptom checkers for further analysis. They categorised symptom checkers by whether they facilitated self-diagnosis, self-triage, or both. They also categorised them according to the type of organisation they were operated by, the maximum number of diagnoses provided and whether they were based on Schmitt or Thompson nurse triage guidelines. These are decision support protocols commonly used in telephone triage for paediatric and adult consultations, respectively.
To evaluate the diagnosis and triage performance of the symptom checkers, they used 45 standardised patient vignettes. They say they used this method to assess the performance of the symptom checkers, because this method is commonly used by physicians and other clinicians on their diagnostic ability and management decisions. These 45 clinical vignettes were further divided as either "common" or "uncommon" diagnoses. Triage advice was further divided into three groups:
- Emergency, which included advice to call an ambulance, go to the emergency department, or see a general practitioner immediately.
- Non-emergency, which included advice to call a general practitioner or primary care provider, see a general practitioner or primary care provider, go to an urgent care facility, go to a specialist, or go to a retail clinic.
- Self care, which included advice to stay at home or go to a pharmacy.
Each standardised patient vignette was entered into each website or app, and resulting diagnosis and triage advice was recorded.
What were the basic results?
The 23 symptom checkers included in this study were based in the UK, US, the Netherlands and Poland. The 45 standardised patient vignettes used to assess the performance of these symptom checkers included 26 common and 19 uncommon diagnoses.Performance on diagnosis
Overall, the correct diagnosis was listed first 34% of the time. For different levels of triage, the percentage of the correct diagnosis being listed first is below:
- 24% (95% confidence interval (CI) 19% to 30%) for emergency evaluations
- 38% (95% CI 32% to 34%) for non-emergency evaluations
- 40% (95% CI 34% to 47%) for self care evaluations
The included online symptom checkers correctly gave triage advice 57% of the time. For different levels of triage, the percentage of correct advice is below:
- 80% (95% CI 75% to 86%) for emergency care evaluations
- 55% (95% CI 47% to 63%) for non-emergency evaluations
- 33% (95% CI 26% to 40%) for self care evaluations
How did the researchers interpret the results?
Researchers concluded by saying, "Physicians should be aware that an increasing number of their patients are using new internet-based tools such as symptom checkers and that the diagnosis and triage advice patients receive may often be inaccurate. For patients, our results imply that, in many cases, symptom checkers can give the user a sense of possible diagnoses, but also provide a note of caution, as the tools are frequently wrong and the triage advice overly cautious."
They added, "Symptom checkers may, however, be of value if the alternative is not seeking any advice or simply using an internet search engine. Further evaluations and monitoring of symptom checkers will be important to assess whether they help people learn more and make better decisions about their health."
This audit study showed that online symptom checkers sometimes correctly diagnose and advise people according to their symptoms, but they can be inaccurate. Though the appropriate triage advice was only accurate, on average, 57% of the time, the study found this advice erred on the side of caution, advising people to seek help.
There are several limitations to this study, including:
- The study did not include real people, but relied on clinical vignettes to assess the performance of the online symptom checkers. These vignettes included medical terms, which would not necessarily be used by people accessing the sites. Actual patients may sometimes find it difficult to express their symptoms or use different terms. On the other hand, people may refine or add more detail if the advice received was not what was expected.
- The study might not have captured all the online symptom checkers available.
- The study does not compare the diagnosis and advice of the online symptom checker to the diagnosis and advise that would have been provided by a doctor.
Overall, it is important to note that symptom checkers should be used as an indicator, and not viewed as an alternative to seeking medical advice, especially if you think it may be a medical emergency.
Like symptom checkers themselves, when it comes to assessing a situation, it is always better to err on the side of caution.
Links To The Headlines
Links To Science
Semigran HL, Linder JA, Mehrotra A, et al. Evaluation of symptom checkers for self diagnosis and triage: audit study. BMJ. Published online July 8 2015
"Suffering from heart disease, stroke and type two diabetes could knock 23 years off life," The Daily Telegraph reports, covering the stark conclusion of a major new UK study. The good news is many chronic diseases, such as stroke, are preventable.
Researchers looked at more than 130,000 deaths over 50 years. They then estimated the life-shortening effects of different diseases alone and in combination, and found these big three conditions significantly shortened lifespan.
The researchers used a large group and long timespan to make their estimates, giving us confidence in their main conclusions. But they are based on averages.
Each person's risks and lifespan is individual, and it is never too late to improve your health, even if you do have one or more chronic conditions: you can work towards maintaining a healthy weight, exercising more, eating healthily, not smoking, and not drinking too much alcohol.Where did the story come from?
The study was carried out by researchers from the Emerging Risk Factors Collaboration co-ordinated by the University of Cambridge.
It was funded by the UK Medical Research Council, the British Heart Foundation, the British Heart Foundation Cambridge Cardiovascular Centre of Excellence, the UK National Institute for Health Research Cambridge Biomedical Research Centre, the European Research Council, and the European Commission Framework Programme 7.
A number of study authors declared potential financial conflicts of interest relating to funding from pharmaceutical companies, health trust funds and not-for-profit research organisations.
The study was published in the peer-reviewed Journal of the American Medical Association (JAMA).
Both The Guardian and The Daily Telegraph reported the main findings accurately, although neither discussed any limitations. Limitations are important to remind the reader no study is perfect or completely accurate.
The first line of The Telegraph's story told readers the diseases behind the 23-year life loss are largely preventable for "8 out of 10 people". This figure doesn't appear to have been taken from the main study publication, so we can't confirm whether or not this is accurate.
The Telegraph also used the term "heart disease", but the researchers specifically looked at people who had a heart attack (myocardial infarction). While a heart attack can be a common complication of heart disease, not everyone with heart disease will have one.
Nonetheless, it is well known you can reduce your risk of these conditions by living healthily, so there is something you can do about it.What kind of research was this?
This analysis of two large cohort studies looked at the impact of diabetes, stroke and heart attack on life expectancy.
The researchers say more and more people are living with one or more conditions that increase their chances of dying early. The conditions of interest were heart attack, stroke and type two diabetes.
The researchers wanted to know the impact on lifespan of having more than one of these three conditions, looking at a large group of people over a significant amount of time.
To do this, they analysed some large and long-term cohort data sets. This is one of the most effective ways of estimating the impact of lifestyle on death across large groups.
The estimates rely on accurate estimates of lifestyle, usually reported in surveys, as well as having a lot of people in the group to boost reliability and generalisablity.
Such analysis produces averages – what happens to most people most of the time. While very useful, individual risk profiles vary from person to person, and can vary a lot around the average.What did the research involve?
The research team analysed two large cohort studies, both of which had rich sources of lifestyle and medical information, allowing them to estimate the impact of different lifestyles and diseases on life expectancy.
The first and largest cohort was from the Emerging Risk Factors Collaboration. This had 689,300 participants from 91 cohorts, covering around 50 years of survey data from 1960-2007. This collected information on 128,843 deaths up to April 2013. The average age was 53, and most participants were from Europe (69%) or North America (24%).
The second cohort was from the UK Biobank. It was a little smaller, but more relevant to the UK. It had data on 499,808 participants with survey-derived lifestyle information spanning from 2006-10. Data on 7,995 deaths was gathered, the latest from November 2013. The average age was 57, and all from the UK.
Death rates were calculated for those with a history of two or more of the following:
- diabetes mellitus
- heart attack
The impact on lifespan of having each of the three conditions at different ages, alone or in combination, was estimated independently in both cohorts and then compared.What were the basic results?
In men aged 60, a history of any two of the three conditions was associated with a 12-year lower life expectancy. A history of all three of these conditions was associated with 15 years of reduced life expectancy. The estimates were similar for women: 13 years lost for two conditions and 16 years for three.
Life lost was greatest if the history of the conditions was present earlier in life. Estimates in this study started at 40 and ran through until 95.
The highest estimate of life loss was 23 years, the figure picked up by The Telegraph. This related to men aged 40 with a history of diabetes, stroke and heart attack. The loss was only slightly lower in women with the same age and conditions, at 20 years.
Broadly speaking, the impact on risk of death from the three conditions was similar in both cohorts. The researchers found risk of death doubled with one condition, was four times as high with two conditions, and eight times higher with all three. This showed the risk effects were piling on top of each other in an exponential manner, rather than overlapping.How did the researchers interpret the results?
The authors made three main interpretations. First, because of the addition nature of the results, they concluded that, "Our results emphasise the importance of measures to prevent cardiovascular disease in people who already have diabetes, and, conversely, to avert diabetes in people who already have cardiovascular disease."
Second, they said the shortening of life as a result of the three conditions studied was "of similar magnitude to those previously noted for exposures of major concern to public health, such as lifelong smoking (10 years of reduced life expectancy) and infection with the human immunodeficiency virus [HIV] (11 years of reduced life expectancy)."
Finally, they said there were important differences between men and women. "For men, the association between baseline cardiovascular disease (i.e. a history of stroke or MI) and reduced survival was stronger than for women, whereas the association between baseline diabetes and reduced survival was stronger for women."Conclusion
This study used two large cohort-derived data sets to estimate the number of years of life lost as the result of a history of heart attack, stroke or diabetes across different ages.
The study's large size, relevance to the UK and long-term follow-up increases our confidence in its conclusions and their relevance to England and Wales. As with all studies, it has limitations, but these were relatively small and unlikely to affect the main conclusions.
This study shows a history of stroke, type 2 diabetes and heart attack can significantly shorten life expectancy, especially if these conditions are developed earlier in life, at around the age of 40.
But the good news is this is preventable – you can act now to minimise your risk of developing each of these conditions by maintaining a healthy weight, taking more exercise, eating healthily, stopping smoking, and not drinking too much alcohol.
Links To The Headlines
Unhealthy lifestyle can knock 23 years off lifespan. The Daily Telegraph, July 7 2015
Heart disease plus diabetes can knock more than a decade off your life. The Guardian, July 7 2015
Links To Science
The Emerging Risk Factors Collaboration. Association of Cardiometabolic Multimorbidity With Mortality. JAMA. Published online July 7 2015
“Ageing rates vary widely, says study,” BBC News reports. For 12 years, researchers tracked a range of biomarkers associated with the ageing process.
Biomarkers are indicators of how well certain biological processes or systems are functioning.
In this study, the researchers described age-related biomarkers as signs of “gradual and progressive deterioration of integrity across multiple organ systems”.
The biomarkers used included cholesterol levels, gum health and body mass index, among others.
The idea being that, for example, your chronological age could be 30, but you could have the cholesterol levels of a typical 50-year-old.
Researchers looked at just over 1,000 mainly white adults in New Zealand followed from birth to age 38, and information on the biomarkers was collected from the ages of 26 to 38.
The study found that people who had a higher “biological age” also had a higher “pace of biological ageing”. Both were associated with poorer physical and cognitive function, feeling less healthy, and looking older at age 38.
These early stage results will need to be confirmed in larger and broader samples. The idea is that the methods used in the study could eventually be useful in assessing the effectiveness of any future anti-ageing treatments.
The obvious question is: What can people do to slow down their pace of ageing? There is currently no definitive answer to that question. What we do know is regular exercise, a balanced diet and maintaining a healthy weight will give you the best chance of keeping healthy.
Where did the story come from?
The study was carried out by researchers from Duke University and other research centres in the US, UK, Israel and New Zealand. It was funded by the US National Institute on Aging, UK Medical Research Council and the Jacobs Foundation. The New Zealand centre received funding from the New Zealand Health Research Council, and another author received support from the Yad Hanadiv Rothschild Foundation.
The study was published in the peer-reviewed journal Proceedings of the National Academy of Sciences (PNAS) of the USA. The study has been published on an open-access basis, so it is free to read online or download as a PDF.
While the majority of the UK media’s reporting of the study was accurate and informative, the Mail Online decided to go on a flight of fancy with the question: “Has science finally cracked the secret of eternal youth?” The obvious answer being: “No”.
What kind of research was this?
This was an analysis of data from a cohort study, which aimed to develop ways to assess “biological ageing” in young adults.
The global population is ageing, and increasing age is linked to more disease and disability. Because of humans’ long life span, much of the research into ageing is done in animals with short lifespans, or in older adults, many of whom already have age-related illnesses. The researchers say that one of the reasons why younger people are not studied is that assessing biological ageing in this age group is controversial, as there are various possible indicators, and findings have been mixed. They wanted to see if they could develop reliable ways to do this.
If there were such measurement tools, researchers would like to use these to give an early indication of whether any new “anti-ageing” treatments might be working. This would be quicker than having to wait until people develop age-related diseases or to see how long they live.
This is an appropriate approach to developing these measures, but ideally the research would continue to follow up people, to see if their measures correctly predict health in later life, or their lifespan.
What did the research involve?
The researchers studied 1,037 adults from Dunedin in New Zealand, who had been followed up from birth to age 38. They assessed a range of biological characteristics tested at age 26, 32 and 38, to see if some people seemed “biologically older” than others of the same age, and whether people aged at different rates.
The researchers first looked at biological age, using what was known as the “Klemera-Doubal method”, which had been shown to be a better predictor of risk of death than a person’s age alone in a previous US study. This method assesses 10 biological characteristics, including tests of lung function, blood pressure and cholesterol, among others.
They used the Klemera-Doubal method to assess biological age in their study participants at age 38. They then looked at 18 different biological characteristics measured in participants at ages 26, 32 and 38, to see how much they had changed. The characteristics assessed are ones which change with age. They included assessments of the heart and blood (cardiovascular), metabolic and immune systems, as well as the kidneys, liver, gums, lungs and DNA. Some of these characteristics were also included in the biological age calculation.
They used this information to calculate each person’s “pace of ageing” compared to the average change over one year within the group. They then compared whether those with an older Klemera-Doubal biological age showed a more rapid “pace of ageing” than those with a younger biological age.
Finally, they compared physical and cognitive function, and self-rated health among those with different biological ages or pace of ageing. They also got blinded raters to guess how old individuals were from a photo, to see if this differed among those with different biological ages or pace of ageing.
What were the basic results?
The researchers found that, according to the Klemera-Doubal method, their sample of 38-year-olds had biological ages ranging from 28 to 61 years old.
The 18 biological characteristics they followed showed different rates of change in different people from the ages of 26 to 38. They calculated people’s “pace of ageing” based on these characteristics, and found that some people showed zero years of biological change per chronological year, while others showed almost three years of biological change per chronological year.
People with an older biological age had a more rapid pace of ageing from the ages of 26 to 38 than those with a younger biological age. Each year increase in biological age compared to actual age added a 0.05 year increase in pace of ageing. So, a person who was 38 but had a biological age of 40 was estimated to have aged 1.2 years faster over the past 12 years, compared to a person who had a biological age of 38.
They also found that at age 38, those with a higher biological age or faster pace of ageing performed less well on physical and cognitive function tests than those with a younger biological age or slower pace of ageing. Those with a higher biological age or faster pace of ageing had also rated themselves as less healthy and were estimated to be older based on facial appearance by volunteers who did not know the participants’ ages.
How did the researchers interpret the results?
The researchers concluded that, “young individuals of the same chronological age varied in their 'biological ageing'” and that “already, before midlife, individuals who were ageing more rapidly were less physically able, showed cognitive decline and brain ageing, self-reported worse health, and looked older”. They suggest that these measures of biological ageing in young adults could be used to identify causes of ageing and evaluate anti-ageing treatments.
This study has developed a new method of assessing the “pace of biological ageing” over time in adults under 40. It showed an association between this measure and another measure of biological age, as well as physical and cognitive function, and how healthy people felt and how young they looked.
In some ways, these results are unsurprising, as the biological measures assessed are measures relating to health, such as blood pressure and cholesterol, as well as measures of fitness and weight.
These results will also need to be confirmed in larger and broader samples – for example, of different ethnicities – as the study was in mainly white participants. Longer-term studies would also be needed to assess whether these measures predict health outcomes at later ages, or lifespan.
As for practical implications, this sort of measure is most likely to be used in research. It’s unlikely that individuals will be able to use this method to calculate their biological age, as the measures used need blood and other clinical tests, and getting the “pace of ageing” needs measurements collected over 12 years. We also don’t yet know whether interventions, either lifestyle or drug treatments, will impact this “biological ageing”.
Based on what we already know, to maximise your chances of living a long and healthy life, taking steps such as maintaining a healthy weight, eating a varied and balanced diet, keeping physically active, moderating your consumption of alcohol and avoiding smoking are likely to be your best bet.
Links To The Headlines
Ageing rates vary widely, says study. BBC News, July 7 2015
Why you might be 20 years older than your actual age. The Daily Telegraph, July 6 2015
Old before your time? People age at wildly different rates, study confirms. The Guardian, July 6 2015
Think you look old? It might be your ‘biological age’. Metro, July 7 2015
How to stay young: The 38-year-olds whose biological ages range from 28 to 61. Daily Express, July 6 2015
Links To Science
Belsky DW, Caspi A, Houts R, et al. Quantification of biological aging in young adults. PNAS. Published online July 6 2015