You don't need to be signed in to read BMJ Blogs, but you can register here to receive updates about other BMJ products and services via our site.

Welcome to the BMJ Open blog. BMJ Open is an open access journal, dedicated to publishing medical research from all disciplines and therapeutic areas.

Find out more about the journal here.

We will be updating the blog with news about the journal, highly accessed papers, press coverage, events and matters of interest in the open access and publishing world, and anything else that catches our eye.

BMJ Open now publishes cohort profiles

22 Aug, 14 | by Richard Sands, Managing Editor

 

BMJ Open currently publishes articles reporting research results or study protocols. We have now expanded our scope to include cohort profiles, articles that describe major, ongoing research cohorts.

What’s the difference between a protocol, a cohort profile and a research paper?
Detailed information about cohort profiles is in our instructions for authors. In brief, cohort profiles will describe large, collaborative prospective studies that identify a group of participants and follow them for long periods. They will usually be population based, with sufficient funding to ensure their intended lifespan, and the original investigators must welcome wide use of the datasets beyond their own research group.

We will publish cohort profiles to provide information on a cohort’s establishment that goes beyond what can reasonably be described in the methods section of a research paper and to advise other researchers of existing datasets and opportunities for collaboration.

If a study has yet to begin recruiting participants, is still recruiting or is still collecting baseline data, please submit the study protocol. If you have completed baseline recruitment and have at least baseline data to publish, we would consider this a cohort profile as long as the cohort meets our other requirements.

We publish protocols to alert researchers to forthcoming research and to explain how specific research questions will be answered. Research papers are traditional results papers and should address a specific research question. Many cohort studies are conducted at a single institution by a single research group with no plans to answer further questions. Here “cohort study” is a research method. We welcome protocol and results papers for these studies but would not consider cohort profiles.

Why publish cohort profiles?
When presented with cohort studies to review, editors, peer reviewers and readers often think “exactly how were patients recruited? how representative were they of the wider population? were the questionnaires used to gather information on diet reliable?” and so on; things that too often are not well enough reported in research papers.

There is a clear advantage to publishing detailed profiles of ongoing cohort studies in an open access journal like BMJ Open, so anyone interested can easily access them when planning or appraising studies that arise from them. We hope to generate an ongoing database for answering many different research questions.

Will cohort profiles be peer-reviewed?
Cohort profiles will be externally peer-reviewed as normal, regardless of the cohort’s age or funding status and article publishing charges will apply as for research papers.

Anal sex between young men and women often seems coercive and painful

13 Aug, 14 | by flee

Anal sex between young men and women often seems coercive and painful, suggests research published in BMJ Open.

Feedback from young people reveals an oppressive culture around anal sex, with some young men apparently neglecting or not caring about young women’s consent or pleasure – both when they have anal sex and when they talk about it with their friends.

More open discussion is needed to challenge the culture and attitudes surrounding anal sex between young men and women—a subject that people often find  difficult to talk about in many social contexts, say the researchers.

They interviewed 130 16-18 year olds from diverse social and economic backgrounds living in different parts of the country: London; an industrial city in the north; and a rural area in the south west.

The interviews explored the range and meaning of different sexual practices, and included nine group and 71 individual in-depth discussions in 2010, and further interviews of 43 of the in-depth interviewees in 2011.

The group discussions focused on what sexual practices participants had heard of, what they felt about them, and whether they thought their peers would engage in them—and if so, under what circumstances.

During the in-depth discussions, interviewees were also asked what sexual practices they had engaged in, under what circumstances, and how they felt about them. Young people described‚ a culture where men compete to have anal sex with women, even if they expect women to find it painful.

Women also said their male partners repeatedly asked them for anal sex. And their accounts suggest that they had sometimes ended up having anal sex without giving their explicit consent. “Currently, this apparently oppressive context, and indeed the practice of anal heterosex itself, appears to be largely ignored in policy and in sex education for this young age group,” write the researchers.

The interviewees sometimes said that young men wanting to copy what they saw in porn, explained why they had anal sex, but the feedback suggests that other factors are more important, say the researchers.

These include a lack of concern about getting consent, or the levels of pain female partners might experience, and competitiveness among young men to have anal sex with women. ‘People must like it if they do it’ was also given as an explanation by those who hadn’t experienced anal sex, which, the researchers point out, was made alongside the seemingly contradictory expectation that women would find it painful.

Not all men coerce their partners, the researchers emphasise. Some young women may wish to have anal sex, and both partners may find it pleasurable, they add.

But the findings suggest that teachers, parents, and wider society need to talk more openly about anal sex with young people, particularly the importance of “mutuality” – where both partners listen and respond to each others’ desires and concerns, they write.

Attitudes, such as the inevitability of pain for women, or the failure to recognise or reflect on potentially coercive behaviour, seem to go unchallenged, which risks coercion emerging as a dominant element of anal sex, they add.

Cheese still laden with salt, despite many products meeting reduction targets

6 Aug, 14 | by fpearson

The salt content of cheese sold in UK supermarkets remains high, despite many products meeting the recommended government targets on salt reduction, finds research published in the online journal BMJ Open.

And salt content varies widely, even within the same type of cheese, the findings show, prompting the researchers to call for much tougher targets on salt lowering.

A high dietary salt intake is linked to high blood pressure, which is a risk factor for stroke, heart attacks, heart failure and kidney disease. It also increases the risk of stomach cancer and osteoporosis, and is indirectly linked to obesity.

Salt reduction is widely recognised to be one of the most cost effective ways of improving public health, and at the 66th World Assembly, all countries unanimously agreed to cut their salt intake by 30% towards a target of 5 g/day by 2025.

The current recommended dietary salt intake in the UK is 6 g/day, but is widely exceeded, according to dietary surveys. Cheese is a major contributor to dietary salt intake, with the average person consuming 9 kg of cheese every year.

The researchers analysed the salt content (g/100 g) of 612 different cheeses produced in the UK or imported from overseas and sold in the seven major UK supermarket chains in 2012. This information was collected from the product packaging and nutritional information panels.

In general, salt content was high, averaging 1.7 g/100 g of cheese. But salt levels varied widely – and not only among different types of cheese, but also within the same type.

Halloumi and imported blue cheese contained the most salt (2.71 g/100 g), while cottage cheese contained the least (0.55 g/ 100 g).

Among the 394 cheeses with salt reduction targets, most (84.5%) had already met them for 2012.

Cheddar and cheddar-style cheeses are the most popular/best-selling lines and 250 of these products were included in the analysis.

On average, salt content tended to be higher in branded (1.78 g/100 g) than in supermarket own label (1.72 g/ 100 g) cheddar and cheddar-style cheeses.

And more of the supermarket own-label cheeses in this category met the 2012 target for salt reduction than did the branded products: 90% compared with 73%.

“Our finding of a high salt content in cheeses sold in the UK is similar to those observed in the USA, Australia, France, Belgium, Canada, New Zealand, South Africa, and Brazil, showing that high levels of salt in cheese is a global challenge,” write the authors.

But they suggest that UK salt reduction targets could be more ambitious.

“The results indicate that much larger reductions in the amount of salt added to cheese could be made, and more challenging targets need to be set,” they conclude.

Prediabetes, PoTS and Portuguese physicians: most read articles in June

9 Jul, 14 | by fpearson

Several new papers made our top ten this month including Mainous et al.’s study on the prevalence of prediabetes in England, and McDonald et al.’s paper on postural tachycardia syndrome predominantly affecting young women. Other popular papers were the recently published paper from Krüsi et al., which explores the effects of criminalisation and policing of sex buyers and a systematic review and network analysis from Cameron et al., comparing antithrombotic agents for the prevention of stroke and major bleeding in patients with atrial fibrillation.

Rank Author(s) Title
1 Mainous et al. Prevalence of prediabetes in England from 2003 to 2011: population-based, cross-sectional study
2 Zhang et al. Spatial analysis on human brucellosis incidence in mainland China: 2004–2010
3 McDonald et al. Postural tachycardia syndrome is associated with significant symptoms and functional impairment predominantly affecting young women: a UK perspective
4 Cameron et al. Systematic review and network meta-analysis comparing antithrombotic agents for the prevention of stroke and major bleeding in patients with atrial fibrillation
5 Krüsi et al. Criminalisation of clients: reproducing vulnerabilities for violence and poor health among street-based sex workers in Canada—a qualitative study
6 Jenkins et al. Effect of a 6-month vegan low-carbohydrate (‘Eco-Atkins’) diet on cardiovascular risk factors and body weight in hyperlipidaemic adults: a randomised controlled trial
7 Dahlen et al. Rates of obstetric intervention and associated perinatal mortality and morbidity among low-risk women giving birth in private and public hospitals in NSW (2000–2008): a linked data population-based cohort study
8 Rao et al. Do healthier foods and diet patterns cost more than less healthy options? A systematic review and meta-analysis
9 Granja et al. What keeps family physicians busy in Portugal? A multicentre observational study of work other than direct patient contacts
10 Abu Dabrh et al. Health assessment of commercial drivers: a meta-narrative systematic review

 

Most read figures are based on pdf downloads and full text views. Abstract views are excluded.

Premature newborn survival 30% higher in high volume neonatal centres

7 Jul, 14 | by flee

The survival of premature newborns in England is 30% higher in specialist units treating large numbers of neonates, reveals an analysis of national data published in BMJ Open.

The advantage is particularly evident for very premature babies born after less than 27 weeks of pregnancy, where the figure rises to 50%, prompting the authors to conclude that new services for newborns should promote delivery of very preterm babies in high volume units.

How best to organise critical care for newborns has been the focus of intense debate, with the results of various studies indicating that centralised care is linked to better outcomes.

But after a review in 2003, the government in England decided to reconfigure services into managed clinical networks (MCNs). These offer some of the benefits of centralisation, while still permitting smaller units to remain open, in a bid to maintain ease and equity of access to services.

To gauge the impact of treatment volume within an MCN, the researchers looked at the survival and health of 20,554 premature babies admitted to 165 NHS hospital neonatal units in England between 2009 and 2011.

These units regularly contribute outcomes data to the National Neonatal Research Database, and were all part of the Neonatal Economic, Staffing, and Clinical Outcomes Project (NESCOP).

Some 17,955 of the babies were born between 27 and 32 weeks of pregnancy; 2559 were born after less than 27 weeks.

In all, 44 of the 165 hospitals (27%) had a level 3 or tertiary level neonatal unit – a designated specialist centre which receives referrals from other hospitals; 81 (49%) had a level 2 unit, which offer high dependency and some short term intensive care; and 39 (24%) had level 1 units, which don’t provide high dependency or intensive care.

Almost one in 10 (1892) of the 20,554 babies were born in hospitals with neonatal units that were classified as high volume, but not tertiary level. And a slightly smaller proportion (1817) were born in neonatal units classified as tertiary level, but not high volume.

High volume was categorised as 3480 days of care each year given to babies born after less than 32 weeks of pregnancy.

There was no difference in survival rates between very premature babies admitted to either level 3 or other level neonatal units at the hospital of their birth. But there was a difference when it came to volume.

Overall, 394 (4.1%) newborns born prematurely after less than 33 weeks of pregnancy died in high volume units compared with 395 (3.6%) premature newborns in other units.

Babies born after less than 33 weeks of pregnancy and admitted to a high volume neonatal unit at the hospital of their birth were around 30% less likely to die within 28 days than those not admitted to this type of unit.

And very premature babies born after less than 27 weeks of pregnancy were almost 50% less likely to die if admitted to a high volume neonatal unit.

“The effect of volume on neonatal outcomes is an important consideration for policy makers deciding the optimal organisation of neonatal specialist services,” conclude the authors.

Future research should also assess the impact of transfers, particularly in light of the reorganisation of MCNs into Operational Delivery Networks following the 2012 Health and Social Care Act, they add.

Poorly understood postural syndrome blights lives of young well educated women

16 Jun, 14 | by fpearson

A debilitating syndrome that causes an excessively rapid heartbeat on standing up, predominantly affects young well educated women, and blights their lives, because it is so poorly understood and inconsistently treated, reveals a small study published in the online journal BMJ Open.

Postural tachycardia syndrome, or PoTS for short, is a by-product of orthostatic intolerance – a disorder of the autonomic nervous system in which the circulatory and nervous system responses needed to compensate for the stress put on the body on standing upright, don’t work properly.

PoTS is associated with an excessively rapid heartbeat, or tachycardia. Symptoms include dizziness, fainting, nausea, poor concentration, excessive fatigue and trembling, and can be so severe as to make routine activities, such as eating and bathing, very difficult to do.

The impact of the syndrome has been likened to the level of disability associated with serious and debilitating long term conditions, such as chronic obstructive pulmonary disease (COPD) and congestive heart failure.

In the US, PoTS is thought to affect around 170 per 100,000 of the population, one in four of whom is disabled and unable to work.

But the symptoms, and their impact, are frequently not recognised in the UK, or attributed to anxiety, panic disorder, or chronic fatigue syndrome (CFS), say the researchers, who wanted to find out if PoTS affects particular groups, and how.

They therefore assessed 84 members of the national charity and support group, PoTS UK, and 52 patients diagnosed with the syndrome at the NHS falls and syncope clinic in Newcastle, north east England, between 2009 and 2012.

All participants completed a validated set of questionnaires specifically aimed at gauging levels of fatigue; sleepiness; orthostatic intolerance; anxiety and depression; ability to carry out routine tasks; and brain power.

The profile of the two groups was broadly similar, and indicated that people with PoTS are predominantly young – average age of diagnosis 30-33 – well educated to degree or postgraduate degree level, and female.

Poor health had prompted a significant number to change their jobs or give up working altogether, and both groups experienced high levels of fatigue, daytime sleepiness, orthostatic symptoms, anxiety and depression, memory and concentration problems, and considerable difficulty carrying out routine tasks.

Around one in five people had been diagnosed with CFS and a similar proportion had Ehlers-Danlos syndrome (inherited connective tissue disorders), suggesting that there may be an underlying overlapping cause, say the researchers.

Beta blocker drugs, which regulate heart rate, were the most common treatment for PoTS. But altogether, patients reported taking 21 different combinations of drugs. And a significant number were taking nothing at all or just salt.

“Patients with PoTS … have significant and debilitating symptoms that impact significantly on their quality of life,” write the researchers. “Despite this, there is no consistent treatment, high levels of disability, and associated comorbidity.”

They go on to emphasise that their findings indicate that patients with PoTS experience a similar level of disability to people with CFS, but yet don’t receive the same protection in law. “Our experience suggests that some patients never recover, and that a subset will worsen over time,” they conclude.

HIV, prostate cancer and food insecurity: most read articles in May

16 Jun, 14 | by flee

This month’s most read article was Dahlen et al.’s study on the rates of obstetric intervention and associated perinatal mortality among women who give birth in private and public hospitals. Newly-published papers in the top ten most read include O’Brien et al.’s paper on evidence-informed recommendations for rehabilitation with older adults living with HIV. Also proving popular for another month, was He et el’s  paper about salt reduction and it’s relationship to blood pressure, stroke and ischaemic heart disease.

Rank Author(s) Title
1 Dahlen et al. Rates of obstetric intervention and associated perinatal mortality and morbidity among low-risk women giving birth in private and public hospitals in NSW (2000–2008): a linked data population-based cohort study
2 O’Brien et al. Evidence-informed recommendations for rehabilitation with older adults living with HIV: a knowledge synthesis
3 Jenkins et al. Effect of a 6-month vegan low-carbohydrate (‘Eco-Atkins’) diet on cardiovascular risk factors and body weight in hyperlipidaemic adults: a randomised controlled trial
4 Xiong et al. Comparative efficacy and safety of treatments for localised prostate cancer: an application of network meta-analysis
5 Hsia et al. Analysis of variation in charges and prices paid for vaginal and caesarean section births: a cross-sectional study
6 He et al. Salt reduction in England from 2003 to 2011: its relationship to blood pressure, stroke and ischaemic heart disease mortality
7 Rao et al. Do healthier foods and diet patterns cost more than less healthy options? A systematic review and meta-analysis
8 Krijthe et al. Non-steroidal anti-inflammatory drugs and the risk of atrial fibrillation: a population-based follow-up study
9 Neter et al. Food insecurity among Dutch food bank recipients: a cross-sectional study
10 Rees et al. ‘It’s on your conscience all the time’: a systematic review of qualitative studies examining views on obesity among young people aged 12–18 years in the UK

 

Most read figures are based on pdf downloads and full text views. Abstract views are excluded.

Use of cement in partial hip replacement linked to risk of death

12 Jun, 14 | by fpearson

The use of cement in partial hip replacement surgery may be linked to a risk of death – often occurring within minutes - finds research published in the online journal BMJ Open.

The risk is relatively rare. But the alarm was first sounded in 2009, and most of the cases that have come to light have occurred since that date, say the authors, who include the former chief medical officer for England.

This suggests that measures to reduce the risks are not being acted on widely enough, they say.

They base their findings on an analysis of cases submitted between 2005 and 2012 to the National Reporting and Learning System (NRLS) – a database of patient safety incidents associated with the delivery of healthcare across the NHS in England and Wales.

All the cases involved sudden and severe deterioration among patients undergoing partial hip replacement, known as hemiarthroplasty, for fractured neck of femur (broken hip), and associated with the use of cement to help hold the artificial hip joint in place.

This sudden deterioration is referred to as bone cement implantation syndrome or BCIS for short. In each of the cases in this study, it caused either death; cardiac arrest, where the heart stops beating; or periarrest – severe deterioration in the patient’s condition.

Between 2005 and 2012, the NRLS received 62 reports of BCIS, equivalent to one incident for every 2900 hemiarthroplasties performed for fractured neck of femur, indicating that it is a rare occurrence.

In 2012, 22,000 people in the UK underwent partial hip replacement for a fractured neck of femur, although not all these would have involved the use of cement.

But in 41 of the cases reported to the NRLS the patient died, and in most (80%), this was on the operating table. A further 14 patients had a heart attack but were resuscitated; and seven sustained a periarrest from which they recovered.

In most cases (55 out of 62; 89%), these events occurred within minutes of the cement being inserted.

A further 39 cases of hip surgery associated with BCIS were also reported to the NRLS during this period, but were not included because it was not clear whether the procedures specifically related to partial hip replacement for fractured neck of femur.

In 2009, the now defunct National Patient Safety Agency raised the alarm about the use of cement and associated patient harm during hemiarthroplasty and issued guidance to the NHS on how to minimise the risks.

Fifty one of the 62 cases were reported to the NLRS after this date, possibly because of heightened awareness in the wake of the guidance, say the researchers.

But the fact that deaths are continuing to occur “clearly shows that the implementation of mitigation measures set out in the alert was suboptimal, or that their effectiveness is suboptimal, or both,” they write.

In an accompanying video abstract, lead researcher Dr Paul Rutter emphasises that the risk of BCIS remains rare, but not so rare that orthopaedic surgeons don’t need to know about it, or what steps they need to take to reduce it.

Rates of pre-diabetes have tripled over past decade in England

9 Jun, 14 | by fpearson

The prevalence of pre-diabetes – higher than normal blood glucose levels – has tripled within the space of 8 years in England, reveals research published in the online journal BMJ Open.

More than a third of adults in England now have pre-diabetes, the findings suggest, with those who are disadvantaged and of black and minority ethnicity disproportionately affected. If nothing is done to halt this trend, the country faces a steep rise in the prevalence of diabetes, as up to one in 10 of those with pre-diabetes will progress to diabetes every year, warn the authors.

They base their findings on an analysis of data collected for the representative Health Survey for England for the years 2003, 2006, 2009 and 2011 and those participants who had provided a blood sample. In all, the data covered more than 20, 000 people.

Pre-diabetes was classified as a glycated haemoglobin – a measure of blood glucose control – of between 5.7% and 6.4%. Diabetes is usually classified as a glycated haemoglobin of 6.5%.

Analysis of the data showed that the prevalence of diagnosed diabetes rose from 3.55% in 2003 to 5.59% in 2011. But the rise in the prevalence of pre-diabetes was much greater. This rose from 11.6% to 35.3% between 2003 and 2011. Older age, overweight, obesity, high blood pressure and high cholesterol were all associated with pre-diabetes risk.

By 2011, half the survey participants (50.6%) who were overweight with a BMI of more than 25, and aged at least 40, had pre-diabetes. There was no gender difference in rates.

Those living in some of the most deprived areas of the country were more likely to have pre-diabetes in 2003 and 2006, but this association was no longer significant by 2009 and 2011.

But after taking account of age, sex, ethnicity, BMI and high blood pressure, people who lived in the second most economically deprived areas of the country were 45% more likely to have diabetes by 2011.

Although diabetes is associated with more complications than its precursor condition, people with pre-diabetes are still at risk of vascular, kidney, and eye problems, the authors point out.

They admit that the data don’t reveal whether any of the survey participants had been screened or treated for their condition, and while this does not alter the prevalence figures, it could affect the policy implications, they say.

Nevertheless, they describe the rise in the proportion of adults who meet the criteria for pre-diabetes as “extremely rapid,” and conclude: “In the absence of concerted and effective efforts to reduce risk, the number of people with diabetes is likely to rise steeply in coming years.”

Divorce may be linked to higher risk of overweight/obesity among kids involved

4 Jun, 14 | by fpearson

Divorce may be linked to a higher risk of overweight and obesity among children affected by the marital split, suggests research published in the on-line journal BMJ Open.

Boys may be especially prone to excess weight gain, the findings indicate.

The researchers base their findings on a nationally representative sample of more than 3000 pupils attending 127 schools across Norway. All the children were part of the national 2010 Norwegian Child Growth Study.

School nurses measured the height, weight, and waist circumference of the children whose average age was 8, to gauge general overweight, as defined by the International Obesity Task Force (IOTF), and (abdominal) obesity, as defined by a waist to height ratio of 0.5 or more.

The results were stratified by gender and parents’ marital status – married, never married, to include co-habiting, single and separated, and divorced – taking account of influential factors, such as the mother’s educational attainment, ethnic origin and area of residence.

Around one in five (19%) of the children was overweight or obese according to the IOTF definition, while just under one in 10 (8.9%) was (abdominally) obese.

Overall, significantly more of the 1537 girls were overweight or obese than the 1629 boys, but there were no differences in the prevalence of (abdominal) obesity.

More of the children whose parents were categorised as divorced were overweight or obese than those whose parents remained married.

They were 54% more likely to be overweight/obese and 89% more likely to be (abdominally) obese. Children whose parents had never married had a similar prevalence of overweight and obesity to those with married parents.

The findings held true even after taking account of other possible explanatory factors.

But these differences were generally larger for boys whose parents were divorced. They were 63% more likely to be generally overweight/obese than boys whose parents were married. And they were 104% more likely to be abdominally obese.

The absolute differences were 9.9 and 7.4 percentage points, respectively.

The same pattern was seen among girls, but the associations were less marked and, unlike the boys, not statistically significant.

The authors caution that the design of their study does not provide a basis for establishing cause and effect. Furthermore, they were unable to glean how long parents had been divorced, nor were they able to include lifestyle factors such as the children’s normal diet and exercise regime.

But the associations they found are consistent with findings from other studies they say.

Possible explanations for the link could include less time spent on domestic tasks such as cooking; an over-reliance on unhealthier convenience foods and ready meals; and lower household income.

The emotional fall-out of a divorce and resulting stress generated by disruptions in the parent-child relationship, ongoing conflict between the exes, moving home and the need to create new social networks, might also explain the findings, the authors suggest. And boys might just be more vulnerable, they say