By Dr Deepu
Saturday, September 12, 2015
Friday, September 4, 2015
Over 80% of medical students with mental health issues feel they receive poor or only moderately adequate support from their medical schools, finds a small online survey published in Student BMJ today.
Of the 1,122 UK respondents, 30% (343) said they had experienced or received treatment for a mental health condition, and almost 15% (167) revealed that they had considered committing suicide while studying at medical school.
"The number of students reporting mental illness or considering suicide is shocking," says Twishaa Sheth, chair of the BMAâs studentâs welfare committee, adding that "what is more concerning is the lack of independent support available for students."
Student BMJ invited its readers to take part in a survey on the health of medical students. The number of respondents represents around 2% of medical students.
The survey also asked questions about smoking, drinking and alcohol use. In total, 15.8% (177) of respondents claimed they smoked, one quarter reported binge drinking each week, and 10.9% (123) said they had taken illegal drugs more than once.
Furthermore, 8.3% (94) claimed to have tried a legal high, and the same number had used cognitive enhancing drugs to help with revision.
Reasons behind the high rates of mental health problems among medical students are "complex", writes Matthew Billingsley, Editor of the Student BMJ.
"Students often have a relentless timetable of exams as well as having to balance the emotional strain of seeing sick patients and uphold high professional standards," he says, adding that "the demands of the course can cause an over competitive environment that can have a detrimental effect on the health of students."
Deborah Cohen, senior medical research fellow at the University of Cardiff, describes Student BMJâs results as "concerning," but that they are in line with previous research.
A study she carried out found that 15% of 557 respondents from two large UK medical schools had substantial levels of depression and 52% reported substantial levels of anxiety.
Earlier this year, Student BMJ reported that there was not a clear separation between medical school staff with pastoral roles and those who rule on fitness to practice disciplinary issues. This raised concerns about students being able to report a problem without it affecting their final result.
In July, the General Medical Council and the Medical Schools Council issued new guidelines to clarify that teaching and pastoral roles should be separate.
Iain Cameron, chair of the MSC, says "Medical schools take the mental wellbeing of their students seriously. The Student BMJ survey highlights key issues and similar concerns have been raised previously."
"It is crucial that students who have concerns about their health are able to make this known so that they can be provided with the necessary advice and support."
He adds that the MSC would like to work with Student BMJ and colleagues across the sector to promote the new guidelines and other initiatives on student mental health.
Link to research
Over 70% of prescriptions are given to those without a record of mental illness
The proportion of people with intellectual disability in the UK who have been treated with psychotropic drugs far exceeds the proportion with recorded mental illness, finds a study published by The BMJ today.
This suggests that, in some cases, these drugs are being used to manage challenging behaviour rather than for mental illness, say the researchers. They call for changes in the prescribing of psychotropic drugs for people with intellectual disability as well as more evidence on their safety in this group.
People with intellectual disability develop severe mental illness at higher rates than do the general population and may show challenging behaviour.
Concern has existed for many years that psychotropic drugs in general - and antipsychotics in particular (mainly used to treat schizophrenia and bipolar disorder) - are overused in people with intellectual disability, but accurate estimates have been difficult to obtain.
So a team of researchers based at University College London set out to describe rates of recorded mental illness, challenging behaviour, and use of psychotropic drugs in people with intellectual disability in UK primary care.
They analysed data from 571 UK general practices using the The Health Improvement Network (THIN), a large database of electronic health records, and identified 33,016 people with a record of intellectual disability. Average age at study entry was 36 years and average follow-up was five and a half years.
Of 9,135 participants treated with antipsychotic drugs by the end of the study period, 6,503 (71%) did not have a record of severe mental illness.
Of the 11,915 with a record of challenging behaviour, 5,562 (47%) had received antipsychotic drugs, whereas only 1,421 (12%) had a record of severe mental illness.
And of those with a record of prescription of antipsychotics, 26% did not have a record of severe mental illness or challenging behaviour.
New prescriptions for antipsychotics were significantly more common in older people and in those with a record of challenging behaviour, severe mental illness, depression, anxiety, autism, dementia, and epilepsy.
People with a record of challenging behaviour were more than twice as likely to receive a prescription for antipsychotics compared with those without a record of challenging behaviour, say the authors.
Prescription of antipsychotic drugs is disproportionate to the level of recorded severe mental illness and is associated with the presence of challenging behaviour, older age, and diagnoses of autism and dementia, they add.
"Inappropriate use of drug treatment has implications for the individual and for healthcare systems," they warn. "These findings highlight the need for an improved evidence base for use of drugs and optimisation of drug treatment in people with intellectual disability."
Wednesday, September 2, 2015
GSK’s malaria candidate vaccine, Mosquirix™ (RTS,S), receives positive opinion from European regulators for the prevention of malaria in young children in sub-Saharan Africa
24 July 2015
Issued: London, UK
- WHO will now assess how the world’s first malaria candidate vaccine might be used alongside other tools to prevent malaria
GSK announced today that the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) has adopted a positive scientific opinion for its malaria candidate vaccine MosquirixTM, also known as RTS,S, in children aged 6 weeks to 17 months. Following this decision, the World Health Organization (WHO) will now formulate a policy recommendation on use of the vaccine in national immunisation programmes once approved by national regulatory authorities.
RTS,S, which was developed in partnership with the PATH Malaria Vaccine Initiative (MVI), is the first candidate vaccine for the prevention of malaria to reach this milestone. While other vaccines tackle viruses or bacteria, RTS,S has been designed to prevent malaria caused by the Plasmodium falciparum parasite, which is most prevalent in sub-Saharan Africa (SSA). In 2013, there were an estimated 584,000 deaths from malaria with around 90% of these occurring in SSA, and 83% in children under the age of five in SSA.1
The CHMP scientific opinion is a key step in the regulatory process toward making RTS,S available alongside existing tools currently recommended for malaria prevention. The positive opinion for young children was based on the review of data assessing the candidate vaccine’s safety, efficacy and quality. Clinical data submitted for CHMP assessment were mainly from a phase III clinical trial programme involving more than 16,000 young children that was conducted by 13 African research centres in eight African countries (Burkina Faso, Gabon, Ghana, Kenya, Malawi, Mozambique, Nigeria, and Tanzania).
Data from this trial programme demonstrate that over the first 18 months following three doses of RTS,S, malaria cases were reduced by almost half in children aged 5-17 months at the time of first vaccination and by 27% in infants aged 6-12 weeks. At study end, four doses of RTS,S reduced malaria cases by 39% over four years of follow-up in children, and by 27% over three years of follow-up in infants.2 In areas of the highest malaria burden, more than 6,000 clinical malaria cases were prevented over the study period for every 1,000 children vaccinated.2 The efficacy of RTS,S was evaluated in addition to existing malaria control measures, such as insecticide treated bed nets, which were used by approximately 80% of the children and infants in the trial.
Sir Andrew Witty, CEO of GSK said: “Today’s scientific opinion represents a further important step towards making available for young children the world's first malaria vaccine. While RTS,S on its own is not the complete answer to malaria, its use alongside those interventions currently available such as bed nets and insecticides, would provide a very meaningful contribution to controlling the impact of malaria on children in those African communities that need it the most. The work doesn’t stop here and GSK remains committed to investing in R&D for malaria vaccines and treatments to find more ways to tackle this devastating disease.”
Dr David C. Kaslow, Vice President of Product Development at PATH said: “Today marks a significant scientific milestone for the long-standing partnership to develop a vaccine, yet several more steps remain before a malaria vaccine might reach the young children in Africa who most need protection against this deadly human parasite. PATH will continue to work with GSK and other partners to ensure that the evidence is available, as soon as possible, to support informed decision-making on those remaining steps.”
GSK has committed to a not-for-profit price for RTS,S so that, if approved, the price of RTS,S would cover the cost of manufacturing the vaccine together with a small return of around five per cent that will be reinvested in research and development for second-generation malaria vaccines, or vaccines against other neglected tropical diseases.
Following the CHMP positive scientific opinion, two of the WHO’s independent advisory groups, the Strategic Advisory Group of Experts (SAGE) on Immunization and the Malaria Policy Advisory Committee (MPAC) will now jointly review the evidence base for RTS,S and make a joint policy recommendation for how it might be used alongside other tools to prevent malaria in the event the vaccine candidate is approved by national regulatory authorities in SSA. The WHO has indicated that such a policy recommendation may be possible by end of this year.
Following the WHO policy recommendation, GSK will also submit an application to the WHO for pre-qualification of RTS,S. WHO pre-qualification involves a scientific assessment of the quality, safety and efficacy of any new vaccine proposed for introduction in WHO Expanded Programme on Immunization. A pre-qualification decision is used by the United Nations agencies and other large scale public procurement agencies to help inform vaccine purchasing decisions.
Once a WHO pre-qualification is granted, GSK would then apply for marketing authorisation in countries in sub-Saharan Africa on a country-by-country basis. These regulatory and policy decisions would, if positive, enable countries to begin implementation of RTS,S through their universal immunisation programmes.
Both a WHO policy recommendation and WHO pre-qualification are requirements for Gavi, the Vaccine Alliance, to support eligible African countries introducing RTS,S into local immunisation programmes supported by UNICEF.
Notes to Editors
- Mosquirix is the brand name given to this malaria candidate vaccine. Its scientific name, RTS,S, reflects the composition. RTS,S also contains the AS01 adjuvant system.[i]
- RTS,S aims to trigger the body’s immune system to defend against the Plasmodium falciparum malaria parasite when it first enters the human host’s bloodstream and/or when the parasite infects liver cells. It is designed to prevent the parasite from infecting, maturing and multiplying in the liver, after which time the parasite would re-enter the bloodstream and infect red blood cells, leading to disease symptoms.
- The safety and efficacy of RTS,S has been evaluated in a large-scale phase III trial, in which it was administered in three doses, one month apart, with an additional fourth dose given 18 months later. Results from this trial have consistently demonstrated that RTS,S can help to protect children against malaria in endemic countries, when used in addition to other malaria control measures such as bed nets.
- RTS,S is the most advanced malaria vaccine candidate in development globally. It was created in 1987 by scientists working at GSK laboratories. Early clinical development was done in collaboration with the Walter Reed Army Institute for Research. In January 2001, GSK and PATH, with grant monies from the Bill & Melinda Gates Foundation to PATH, entered into a public-private partnership to develop an RTS,S-based vaccine for infants and young children living in malaria-endemic regions in sub-Saharan Africa.
- GSK has invested more than $365 million to date and expects to invest a further $200 to $250 million until development is completed. Between 2001 and the end of 2014, the MVI, supported by grants from Bill & Melinda Gates Foundation, invested more than $200 million to advance the RTS,S project.
- The EMA’s CHMP opinion is a final stage in the Article 58 procedure initiated in July 2014, by which the CHMP gives a scientific opinion, in co-operation with the World Health Organization (WHO), on a medicinal product for human use that is intended exclusively for markets outside of the European Union (EU). This assessment requires medicinal products to meet the same standards as those intended for use in the EU.
2. RTS,S Clinical Trials Partnership, The Lancet. 2015; 386 (9988): 31–45.
Friday, August 28, 2015
This clinical review summarises how to recognise a febrile seizure and rule out other underlying causes. How to manage febrile seizures and how to deal with common questions posed by parents in this situation.
This network meta-analysis compares different eradication treatments forHelicobacter pylori.This showed that concomitant treatments, 10 or 14 days of probiotic supplemented triple treatment, levofloxacin based triple treatment, hybrid treatment and sequential treatment might be most effective for eradicating H pylori.
Monday, August 24, 2015
The Los Angeles Times (8/20, Kaplan) reports in “Science Now” that people “who put in long hours at the office were 33% more likely to suffer a stroke than their colleagues who clocked out earlier,” according to study findings published online yesterday in The Lancet. The study also found that even people “who worked just over 40 hours per week saw a significant increase in stroke risk.”
The New York Times (8/20, Saint Louis) “Well” blog points out that the “new analysis includes data on more than 600,000 individuals in Europe, the United States and Australia, and is the largest study thus far of the relationship between working hours and cardiovascular health.” Included in the analysis were 17 “studies of stroke” that “included 528,908 men and women who were tracked on average 7.2 years,” as well as 25 studies of “coronary heart disease among workers” that involved some “603,838 people.”
TIME (8/20, Basu) reports that the study authors are not sure why longer work hours appear to be linked to an increased risk for stroke, but posited that “working long hours tends to be correlated with risky health behaviors, like drinking more alcohol or sitting for hours at a time.” Such behaviors, in combination “with the stress associated with working overtime, could be a perfect recipe for a stroke or cardiovascular strain.” The Telegraph (UK) (8/20, Knapton) also covers the study.
By Dr Deepu
The Sleep Review (8/20, Wolski) reports on “easy to use, effective, and unobtrusive” alternatives to CPAP for patients with OSA while traveling. Dr. Glenn Adams, medical director and sleep medicine specialist at Sarasota Memorial Health Care System, said one of the most effective options is “Provent, which goes over the nose and creates back pressure to treat OSA,” but is not covered by insurance. The piece also discusses the option of oral appliances.
Thursday, August 20, 2015
By Dr Deepu
FDA grants “fast track” designation to pneumonia drug
The Triangle (NC) Business Journal (8/19, deBruyn, Subscription Publication) reports that Chapel Hill-based drug developer Cempra Inc. received “Fast Track” designation from the FDA to expedite the review process for “Cempra’s experimental drug solithromycin, a treatment for community acquired bacterial pneumonia (CABP).” The drug is “currently in Phase 3 development for the treatment of CABP and Cempra plans a New Drug Application submission in 2016.”
Wednesday, August 19, 2015
Extra vigilance needed when using both types of drugs together
Taking a combination of antidepressants and common painkillers is associated with an increased risk of bleeding soon after starting treatment, finds a study published in The BMJ this week.
The researchers say their results may have been affected by other unmeasured or unknown factors and should be interpreted with caution. However, they suggest special attention is needed when patients use both these classes of drugs together.
Depression produces the greatest decrement in health of all common chronic conditions and depression in older people is an important public health problem.
But concern exists that antidepressants may interact with common painkillers called non-steroidal anti-inflammatory drugs (NSAIDs) to increase the risk of bleeding inside the skull (intracranial haemorrhage).
So a team of researchers based in Korea compared the risk of bleeding among patients treated with antidepressants with and without NSAIDs.
Using the Korean nationwide health insurance database, their study involved over four million people who were prescribed antidepressants for the first time between 2009 and 2013.
NSAID prescriptions were obtained and hospital records were used to identify time to first admission with intracranial haemorrhage within 30 days of a new prescription. Factors that could affect the results, such as age, sex, and use of other medications, were taken into account.
Compared with use of antidepressants alone, the team found that combined use of antidepressants and NSAIDs was associated with a substantially increased bleeding risk.
They found no statistically meaningful differences in risk of bleeding between different types of antidepressant drugs, or with age. Being male was the most common factor for a higher risk of bleeding with combined use of antidepressants and NSAIDs.
"The addition of NSAIDs to antidepressant treatment increased the risk of intracranial haemorrhage within 30 days of the combination starting, especially in men," conclude the authors. "This result adds to evidence confirming the increase of risk with combination use of antidepressants and NSAIDs."
In an accompanying editorial, Dr Stewart Mercer at the University of Glasgow and colleagues at the University of Cambridge, say the results give some cause for concern.
They point out that both types of drug are widely used, and that co-morbidity of the conditions for which these drugs are used is very high - 65% of those with major depression also have chronic pain.
They urge family doctors to be extra vigilant in terms of prescribing behaviour and discussing the risks with patients, especially in deprived areas where "the combination of mental and physical problems (including chronic pain) is very common." And they say further research is required to extend the findings over longer time periods and in differing populations.Link to full
Tuesday, August 18, 2015
Medscape (8/18) reports that an analysis published in the journal Pediatrics found that high-flow nasal cannula therapy “is as safe and efficacious as conventional modes of noninvasive ventilation (NIV) in preterm infants.” The study, which compared high-flow therapy with nasal continuous positive airway pressure, found “no significant differences between groups with respect to a variety of secondary outcomes,” such as the duration of time in the neonatal unit or respiratory support.
According to Lung Disease News (8/18, Semedo), a recent study in the journal CHEST found that psychological conditions such as depression anxiety, or psychosis were associated with a higher risk of hospital readmission for COPD complications. “These psychological disorders are more likely to predict early readmission than other significant factors,” said Gurinder Singh of the University of Texas Medical Branch at Galveston. “This is likely related to the limited ability of these patients to handle the COPD, poor social support or community resources and non-adherence with treatment,” Singh added.
Monday, August 17, 2015
The Guardian (UK) (8/17, Meikle) reports that an online survey by the British anti-tobacco group Action On Smoking and Health found that “experimentation with e-cigarettes is rising among 11- to 18-year-olds in Britain but is most common among those who already smoke or who have done in the past.” The group suggests that the results show it is “unlikely” that e-cigarettes are being used as a gateway drug to tobacco. Also covering the story are the Daily Mail (UK) (8/17, Duell) and the Independent (UK). (8/17, Connor)
The Daily Mail (UK) (8/16) reported that “the bacteria helicobacter pylori” may “be common in patients with chronic obstructive pulmonary disease (COPD).” Research has “found that levels of the bacteria are up to three times higher in people with COPD, and one theory is that infection in childhood may affect the growth of the lungs, making them more vulnerable to disease.”
Regular consumption of sugar sweetened drinks is positively associated with type 2 diabetes independent of obesity status, finds a study published in The BMJ this week.
Artificially sweetened drinks and fruit juice also showed a positive association with type 2 diabetes, but the quality of evidence was limited. None the less, the authors warn that neither artificially sweetened drinks nor fruit juice are suitable alternatives to sugar sweetened drinks for the prevention of type 2 diabetes.
Artificially sweetened beverages have been seen as possible alternatives to sugar sweetened beverages to reduce intake of sugars and energy, and fruit juice has been considered a healthier alternative. However, evidence was not available to clarify whether or not consumption of each of sugar sweetened beverages, artificially sweetened beverages, and fruit juice is associated with risk of diabetes after taking account of obesity status.
To address this question, an international team of researchers led by the MRC Epidemiology Unit at Cambridge University set out to assess whether or not habitual consumption of sugar sweetened drinks, artificially sweetened drinks, or fruit juice was associated with the incidence of type 2 diabetes, and to estimate the 10-year risk attributable to sugar sweetened drinks in the USA and UK.
They analysed the results of 17 observational studies. Design and quality were taken into account to minimise bias. None of these was funded by industry.
They found that habitual consumption of sugar sweetened drinks was positively associated with incidence of type 2 diabetes, independently of obesity status.
The association between artificially sweetened drinks or fruit juice and incident type 2 diabetes was less evident. Yet, the researchers found little evidence for benefits of these beverages, and therefore concluded these drinks are unlikely to be healthy alternatives to sugar sweetened drinks for preventing type 2 diabetes.
They point out that the studies analysed were observational, so no definitive conclusions can be drawn about cause and effect.
However, assuming a causal association, they estimate that two million new-onset type 2 diabetes events in the USA and 80,000 in the UK from 2010 to 2020 would be related to consumption of sugar sweetened beverages.
âAlthough more research on cause and effect needs to be carried out, this study indicates the potential health gains that may be achieved by reducing the consumption of sugar sweetened drinks,â they conclude.Link to article
Saturday, August 15, 2015
The rising proportion of operations carried out as day cases over the past few decades has been good for patients and a much more efficient use of NHS resources, says John Appleby, Chief Economist at the King's Fund, in a databriefing for The BMJ this week.
The article is based on a recent report by the King's Fund: Better Value in the NHS
He explains that, in 1990, a review by the Audit Commission suggested that if all health authorities in England and Wales performed day surgery for 20 common procedures, such as cataract surgery and gallbladder removal, "an additional 186,000 patients could be treated each year without increased expenditure."
Following the review, the Department of Health set up a task force on day surgery along with Â£15m (â¬21m; $23m) of capital funds to expand the number of dedicated day surgery units. By 2001, almost all trusts had at least one unit.
A 2001 follow-up review pushed for further progress: "If all trusts could achieve the levels of the best performers (the upper quartile of the distribution of the percentage of day cases), 120,000 existing inpatients in England and Wales could be treated as day cases to the benefit of all concerned."
Appleby shows that in 1974, around 7% (417,000) of all elective and non-elective procedures in England were carried out as day cases each year. This proportion increased to nearly 35% (6.3 million) by 2013.
As day case patients cost less to treat than patients who stay overnight as inpatients (in 2013-14, the average day case cost was Â£698 and the average elective inpatient case Â£3,375), the increasing proportion of day case activity has helped reduce overall costs, he writes.
But imagine if the switch to day cases had not changed, says Appleby.
Based on national reference costs reported by English hospitals, the total cost of treating the 6.96 million elective day and inpatients in 2013 was around Â£8.9bn. To treat this number of patients, but with the proportion of day cases as observed in 1998 would cost nearly Â£11bn (over 22% more).
By treating more patients as day cases, Appleby estimates that the NHS had in effect saved around Â£2bn by 2013, although he stresses this is likely to be an overestimate as it is based on the average costs of day cases and elective inpatients.
Even though day cases now account for nearly 80% of all elective procedures each year, it is likely that there is still scope for further increases, he adds.
"Assuming the proportion of day cases continues to increase at the same rate for the next decade as it has done in the 15 years since 1998, then, all other things being equal, the total spent on elective care in 2013 would pay for 22% more patient episodes in 2023," he concludes.
Link to article.
Friday, August 14, 2015
Following the BMA's call for a 20% sugar tax to subsidise the cost of fruit and vegetables, experts in TheBMJ this week debate whether a sugar tax could help combat obesity.
Sirpa Sarlio-Lahteenkorva, adviser at the Ministry of Social Affairs and Health in Finland, says that a specific tax on sugar would reduce consumption. "Increasing evidence suggests that taxes on soft drinks, sugar, and snacks can change diets and improve health, especially in lower socioeconomic groups," she writes.
Taxes on specific food categories that are common constituents of poor diets "are practicable because they are simple to administer," she adds.
However, she acknowledges that taxes can only be a partial solution, and suggests that a sugar tax on all products may be more acceptable "because it would treat all sources equally. It could also stimulate reformulated products, with less sugar and hence liable for less tax."
In Finland, the Sugar Tax Working Group recently concluded that the current system of using excise duty is most practicable. "A combination of excise duty for key sources of sugar with tax adjusted based on sugar content would optimally promote health - and product reformulation."
Nevertheless, Professor Sarlio-Lahteenkorva points out that taxes for health face many challenges, as recently seen with Denmark's short experiment with a tax on saturated fat, which seems to have reduced consumption of fats by 10-15% but worries about border trade and lobbing by industry led to its withdrawal. The food industry also argues that consumption taxes are ineffective, unfair, and damage the industry.
"We need fiscal policies that take health seriously," she writes. "Governments must tackle the related adverse health effects, such as diabetes, coronary heart disease, and hypertension. A tax on sugar, preferably with measures that target also saturated fat and salt, and incentives for healthy eating, would help," she concludes.
But Jack Winkler, emeritus professor of nutrition policy at London Metropolitan University, argues that such taxes would be a positive development in principle, but are politically unpalatable and would have to be enormous to have any effect.
He points out that referendums in the United States have led to soft drinks taxes in just one city (Berkeley), while only four of 53 states in WHO-Europe have adopted food taxes, all with the stated aim of raising revenue, not improving health.
Food taxes are also economically ineffective, he adds. Two rigorous UK studies found that a 10% tax would reduce average personal daily intake by 7.5 mL (less than a sip), while a 20% tax would reduce consumption by 4 kcal. "Effects of this size will not reverse global obesity," he argues.
He suggests that cutting product margins on sugar-free soft drinks would be a positive alternative, which would make the healthy choice the cheaper choice - and would would boost companies' profit.
He points out that before and after the recent UK election, government spokespeople stated repeatedly that there will be no new food taxes and immediately rejected the BMA's proposal.
Why are we still debating this idea, he asks? "Nutrition policy needs price instruments, but a more positive selection. Sugar taxes are unlikely to be adopted and would not make much difference anyway," he concludes.
Saturated fats are not associated with an increased risk of death, heart disease, stroke, or type 2 diabetes, finds a study published in The BMJ this week. However, the findings show that trans fats are associated with greater risk of death and coronary heart disease.
The study confirms previous suggestions that industrially produced trans fats might increase the risk of coronary heart disease and calls for a careful review of dietary guidelines for these nutrients.
Guidelines currently recommend that saturated fats are limited to less than 10%, and trans fats to less than 1% of energy to reduce risk of heart disease and stroke.
Saturated fats come mainly from animal products, such as butter, cows' milk, meat, salmon and egg yolks, and some plant products such as chocolate and palm oils. Trans unsaturated fats (trans fats) are mainly produced industrially from plant oils (a process known as hydrogenation) for use in margarine, snack foods and packaged baked goods.
Contrary to prevailing dietary advice, a recent evidence review found no excess cardiovascular risk associated with intake of saturated fat. In contrast, research suggests that industrial trans fats may increase the risk of coronary heart disease.
To help clarify these controversies, researchers in Canada analysed the results of observational studies assessing the association between saturated and/or trans fats and health outcomes in adults.
Study design and quality were taken into account to minimise bias, and the certainty of associations were assessed using a recognised scoring method.
The team found no clear association between higher intake of saturated fats and all cause mortality, coronary heart disease (CHD), cardiovascular disease (CVD), ischemic stroke or type 2 diabetes, but could not, with confidence, rule out increased risk for CHD death. They did not find evidence that diets higher in saturated fat reduce cardiovascular risk.
However, consumption of industrial trans fats was associated with a 34% increase in all cause mortality, a 28% increased risk of CHD mortality, and a 21% increase in the risk of CHD.
Inconsistencies in the included studies meant that the researchers could not confirm an association between trans fats and type 2 diabetes. And they found no clear association between trans fats and ischemic stroke.
The researchers point out that the certainty of associations between saturated fat and all outcomes was "very low," which means that further research is very likely to have an important impact on our understanding of the association of saturated fats with disease. The certainty of associations of trans fat with CHD outcomes was "moderate" and "very low" to "low" for other associations.
They also stress that their results are based on observational studies, so no definitive conclusions can be drawn about cause and effect. However, they say their analysis "confirms the findings of five previous systematic reviews of saturated and trans fats and CHD."
And they conclude that dietary guidelines for saturated and trans fatty acids "must carefully consider the effect of replacement nutrients."