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(1) Increasing numbers of people are failing to recognise they have a weight problem (2) Study on government's controversial choice of HPV vaccine (3) Doctors are key to tackling knife violence, says expert
(1) Increasing numbers of people are failing to recognise they have a weight problem (Changing perceptions of weight in UK: comparison of two population surveys) http://www.bmj.com/cgi/content/abstract/337/jul10_1/a494 (Editorial: Public perception of overweight) http://www.bmj.com/cgi/content/extract/337/jul10_1/a347
More and more people are failing to recognise they are overweight, despite an actual rise in the number of people who are clinically "overweight" or "obese", according to research published on bmj.com today.
It is well known that women often view themselves as 'too fat' while men typically underestimate their weight. But how far has people’s perception of their weight changed with the growing obesity epidemic?
Researchers from the Health Behaviour Research Centre at University College London, compared data taken from two household surveys carried out in 1999 and 2007. In each survey participants were asked to give their height and weight (from which their Body Mass Index (BMI) and clinical weight category could be determined) and also categorise themselves as either: 'very underweight', 'underweight', 'about right', 'overweight' or 'very overweight'.
The 2007 survey also included 'obese' as a category.
Professor Jane Wardle and colleagues found the proportion of respondents whose weight placed them in the clinically obese category had nearly doubled in eight years from 11% in 1999 to 19% in 2007. Yet, those whose weight put them in the overweight category were less likely to think that they were overweight in 2007 than in 1999.
In 1999, 43% of the population had a BMI that put them in the overweight or obese range, of whom 81% correctly identified themselves as overweight. But in 2007, 53% of the population had a BMI in the overweight or obese range, but only 75% of these correctly classed themselves as overweight.
The researchers suggest that the growing division between actual and perceived weight may be due to overweight becoming more widespread in the population and the appearance of mild overweight being increasingly accepted as 'normal'. These changes may have increased the level at which people perceive themselves to be overweight.
According to the authors, these perceptions are reinforced by media images of people who are morbidly obese, which add to the misconception that extremely high weights are required to meet the medical criteria for overweight. This can also increase the stigma attached to the labels 'overweight' and 'obese'.
The authors warn that despite media and health campaigns aimed at raising awareness of healthy weight, increasing numbers of overweight people are failing to recognise that their weight is a cause for concern, or that messages about healthy eating and exercise are aimed at them.
Overweight people, who underestimate their body weight, may be ignoring important messages about modifying their lifestyles, claims Professor Sara Bleich from John Hopkins Bloomberg School of Health in an accompanying editorial.
According to Bleich, the key to correcting misconceptions about weight is to treat obesity as a multilevel problem - focusing on broader society as well as the individual. Educating the entire population on the importance of a healthy lifestyle, rather than focusing on overweight individuals, may also reduce weight related stigma.
Contacts: Jane Wardle, Health Behaviour Research Centre, University College London, London, UK Email: j.wardle@ucl.ac.uk Sara Bleich, Department of Health Policy and Management, John Hopkins Bloomberg School of Public Health, Baltimore, USA Email: sbleich@jhsph.edu
(2) Study on government's controversial choice of HPV vaccine (Economic evaluation of human papillomavirus vaccination in the UK) http://www.bmj.com/cgi/content/abstract/337/jul17_2/a769 (Editorial: Human papillomavirus vaccination in the UK)http://www.bmj.com/cgi/content/extract/337/jul17_2/a842
The UK government may save up to £18.6 million a year by deciding to use the HPV vaccine Cervarix, given that it is equally effective as the more expensive Gardasil in preventing cervical abnormalities, according to a study published on BMJ.com today.
Every year in the UK nearly 3 000 women are diagnosed with cervical cancer caused by human papillomaviruses (HPV). Some of these viruses also cause over 100 000 diagnosed cases of anogenital warts.
There are a number of different strains of HPV, but types 16 and 18 are known to be responsible for seven in ten cases of cervical cancer, while types 6 and 11 are linked to at least nine in ten cases of the less serious anogenital warts.
Two HPV vaccines have demonstrated similar efficacy against cervical abnormalities due to types 16 and 18 up to nearly five years, one which protects against types 16 and 18 only (a bivalent vaccine, Cervarix) and another which protects against types 6 and 11 as well (a quadrivalent vaccine, Gardasil).
The Department of Health recently chose Cervarix for use in the HPV immunisation programme in the UK which begins in September. All schoolgirls aged 12 and 13 will be routinely vaccinated, and it will be followed by a two year catch-up programme for girls up to 18 years old.
Jit and colleagues predict that the HPV vaccination programme in the UK aimed at 12-13 year-old girls is highly likely to be cost-effective provided that protection lasts for more than 10 years.
They explain that, because the quadrivalent vaccine includes the added protection against non-cancerous anogenital warts, the bivalent vaccine must be priced £13-21 less per dose than the quadrivalent vaccine to be equally cost-effective.
The researchers say that the vaccination programme would also provide "herd immunity" benefits to those in the population who had not received the vaccine, from reduced HPV prevalence in the population.
They also find that vaccinating boys would not be cost effective because, if 80% of girls were covered, it is likely that most cases of cervical cancer would be prevented, as well as most cases of anogenital warts if the quadrivalent vaccine was used.
Using a bivalent vaccine priced at £13-21 less per dose than the quadrivalent vaccine translates to financial savings of between £11.5-£18.6 million from the vaccine price alone in the first year of the programme, if 80% of 12-year-olds in the UK receive the full three-dose vaccine series, estimates Professor Jane Kim from the Harvard School of Public Health, in an accompanying editorial.
"The decision to select the bivalent vaccine implies that the Department of Health is willing to accept foregone health benefits (and additional cost-savings) from averting [non-cancerous] cases of genital warts for the reduced financial outlay, which may be allocated to other priority investment in health", says Kim.
Although the authors assume coverage of 70%-90% and a previous study* in the BMJ reported encouraging uptakes of the first and second vaccine doses in schoolgirls, it is unclear, says Kim, what the uptake rates will be for the three-dose series, and this will have a significant impact on the direct and indirect benefits of the vaccination programme.
Ensuring equitable access to the vaccine may also increase overall success of the vaccination programme and help mitigate disparities in cancer risk across socioeconomic groups. And, because nearly one third of cases of cervical cancer are attributable to HPV types that are not covered by vaccines, cervical screening will continue to be a vital component of efforts to prevent cancer, she adds.
Notes to Editors: * BMJ May 2008; 336: 1056–1058
Contacts: Mark Jit, Modelling and Economics Unit, Centre for Infections, Health Protection Agency (HPA), London, UK Email: cfipressoffice@hpa.org.uk Jane Kim, Program in Health Division Science, Department of Health Policy and Management, Harvard School of Public Health, Boston, USA Email: jkim@hsph.harvard.edu
(3) Doctors are key to tackling knife violence, says expert (Editorial: Tackling knife violence) http://www.bmj.com/cgi/content/extract/337/jul16_2/a849
Every hospital emergency department should share information about violent incidents with local crime reduction agencies to tackle the problem of knife crime, says an expert in this week's BMJ.
Professor Jonathan Shepherd, Director of the Violence Research Group at Cardiff University, believes anonymous data should be collected by all emergency departments on the locations and times that violence occurs and the types of weapons used, and then shared with crime reduction partnerships, so that violence "hotspots" can be identified and targeted.
Evidence shows that increasing the perceived likelihood of being caught is more of a deterrent than the severity of sentence, and that police interventions that target "hotspots" are particularly effective, he writes.
Since 2000, violence in England and Wales has become considerably less frequent, but injuries may have become more serious, says Shepherd. Hospital statistics show that rates of hospital admission in England for violence of all types increased (from 82.7/100 000 in 2000-1 to 114.1/100 000 in 2006-7) while admissions due to knife violence also increased (from 8.5/100 000 to 11.3/100 000). However, at the same time, treatment in emergency departments after violence decreased from about 850 to 620 per 100 000.
"It is not safe to assume that the most serious violence, including knife and gun violence, will have been reported", says Shepherd. Indeed, many serious violent incidents which result in treatment are not reported to the police due to fear of reprisal or an inability to identify assailants.
Shepherd points out that evaluation of partnership work over the past 10 years shows that the 350 Crime Reduction Partnerships to which the NHS, local authorities and police all contribute has confirmed that an integrated approach and data sharing significantly reduces violence compared with the police and local authorities working alone.
He suggests that alongside measures that decrease the availability of knives, a prevention policy of hospitals sharing information with other agencies is vital to tackling knife violence.
Key to this will be emergency medicine consultants being directly involved in partnership prevention work, including attending meetings with the police and local authority representatives, he concludes.
Contacts: Jonathan Shepherd, Director, Violence Research Group, Cardiff University, Cardiff, UK Email: shepherdjp@cardiff.ac.uk
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