Depressed? You must like chocolate

New study finds marked association between depression, eating chocolate

CHICAGO - People who are depressed eat more chocolate than people who are not, U.S. researchers said on Monday, in a study that puts numbers behind the link between mood and chocolate.

They said people who were depressed ate an average of 8.4 servings of chocolate per month, compared with 5.4 servings among those who were not.

And people who had major depression based on results of a screening test ate even more — 11.8 servings per month. A serving was considered to be one small bar, or 1 ounce (28 grams), of chocolate.

Depressed mood was significantly related to higher chocolate consumption," Dr. Natalie Rose of the University of California, Davis, and University of California, San Diego, and colleagues wrote in the Archives of Internal Medicine.

Many people consider chocolate a mood-booster but few studies have actually confirmed the connection between the confection and mood. And most studies have looked only at women.

Rose and colleagues studied the relationship between chocolate and mood among 931 women and men who were not using antidepressants. People in the study reported how much chocolate they consumed and most also completed a food frequency questionnaire about their overall diet.

Their moods were assessed using a commonly used depression scale. What they found was a marked association between chocolate consumption and depression. And unlike other studies that looked only at women, the link was true of both men and women.

Depression may stimulate cravings
What the study could not say was why people who are depressed eat more chocolate.

It could be that depression stimulates chocolate cravings, and people eat chocolate as a sort of self treatment, confirming some studies on rats that suggest chocolate can improve mood, the authors said.

Or, it could be that depression may stimulate chocolate cravings for some other reason without providing any mood benefit. People in the study did not have any such "treatment benefit" from chocolate, the team said.

And they said it may be that eating a lot of chocolate actually causes people to feel depressed, another possible explanation for the association they saw in the study.

It may be something physiological about chocolate, such as providing additional antioxidants. Or the mood-boosting effect of chocolate could be fleeting, like the temporary euphoria from drinking alcohol, leaving people feeling even lower after the brief euphoria has passed.

"Distinguishing among these possibilities will require different study designs," the team said.

They said future studies will be needed to determine whether chocolate is a cause of depression, or a temporary salve.

 

Call to end exclusion of elderly from drug trials

A charter against ageism in clinical trials is being launched by a group of geriatricians from Europe.

The EU funded project, called PREDICT, says treatments are less likely to be tested on older people even though the elderly take the most medication.

Trial results from younger people cannot always be extrapolated to the elderly, say the authors.

They want older people to have access to drugs which have been shown to be safe and effective for their age group.

PREDICT set out assess the extent to which the elderly were excluded from clinical trials and to come up with solutions.

They surveyed the medical literature on treatments for conditions which were common among elderly people and found clear evidence that the elderly were underrepresented.

For example, the average age of patients in clinical trials of treatments for high blood pressure is 63, although 44% of patients are over 70 when they are first diagnosed.

The researchers interviewed health professionals in nine countries and conducted more than 50 focus groups with elderly people and their carers.

They concluded that both doctors and patients felt that more elderly people should be included in trials.

"If treatments are not evaluated for elderly people it is difficult for doctors to balance the risks and benefits" said Dr Gary Mills, Director of Medical Economics and Research Centre, Sheffield, who is one of the co-ordinators of the project.

'Practical steps'

Dr Mills said people conducting trials may need to take practical steps to help the elderly participate, such as going to their house rather than expecting them to travel.

The British Geriatrics Society welcomed the project. Their spokesman Professor David Oliver said the under-representation of elderly people in clinical trials was a "serious problem".

He said it was easier for drug companies to carry out testing on younger people, but this means the trial group is "not representative" of the majority of taking medicines.

He added that drugs might be more or less effective on the elderly than younger older people, and might have different side effects.

"Doctors try to practise evidence-based medicine, but this is not possible if there are not enough elderly people in the trials."

'Ageism'

Stephen Jackson, Professor of Professor of Clinical Gerontology from King's College, London, said the reasons why not enough elderly people are included in trails go beyond practical difficulties.

"The elderly are underrepresented in clinical trials because of ageism," he said.

He pointed out that elderly people often have more than one condition and that makes it more complicated for those conducting trials to include them.

People conducting trials think it is "too much trouble" to include older people he said. This would not change without regulation, he added.

Age Concern welcomed the initiative. Andrew Harrop their Head of Policy said: "More and more people will be living longer and many with multiple long-term conditions.

"Addressing the shortfall in the numbers of older people taking part in clinical trials is crucial to ensure the well-being of a growing proportion of the population."

Test 'predicts breast cancer resistance'

A genetic test could one day spot breast cancer patients most at risk of relapsing after treatment with a commonly used powerful chemotherapy.

The find could spare patients the side-effects of a drug destined to fail.

US researchers tested tumours for activity from two genes which appeared to cut the effectiveness of a class of cancer drugs.

UK cancer experts said it was another step towards "personalised" cancer treatment.

The fact that a drug may be highly effective in some patients, but not others, cannot be easily explained.

Scientists now believe that the molecular properties of patients and their tumours may be the key to understanding this - and choosing the right type of treatment.

The team from the Dana-Farber Cancer Institute, in Boston, Massachusetts, scanned the genetic code of tumours taken from women who had undergone treatment, looking for differences which could account for differences in outcome, focusing on a single class of drugs called anthracyclines.

They found a small region on a single chromosome, and within it two genes which seemed to be unusually active in drug-resistant tumours.

When checks were made on samples from 85 other women, those with high levels of activity from these two genes were those who did worst when treated with anthracyclines.

They believe that by checking tumours in advance, treatment regimes could be changed to those involving alternative drug types.

'Appropriate treatment'

Dr Eric Winer, director of the Breast Oncology Center at Dana-Farber, said: "While this work remains preliminary, it may ultimately help us use the anthracyclines in a much more thoughtful manner and allow us greater ability to personalise our breast cancer treatments to the tumour and the patient."

UK cancer charities welcomed the research, although they cautioned that it could be some time before the results were confirmed and any test developed.

Meg McArthur, from Breakthrough Breast Cancer, said: "This research is a step towards discovering why some patients benefit more than others from a common form of chemotherapy.

"Research like this is important for identifying the appropriate treatment for individual patients."

Oliver Childs, from Cancer Research UK, said: "Finding ways to predict how patients will respond to chemotherapy is important to help them benefit as much as possible from their cancer treatment.

"It is too early to say whether this research will lead to a predictive test, but work like this inches us a little closer towards an age of personalised cancer treatment."

Diabetes sugar 'can go too low'

Intense treatment to lower blood sugar in patients with diabetes could prove nearly as harmful as allowing glucose levels to remain high, a study says.

Cardiff researchers looked at nearly 50,000 patients with type 2 diabetes and found the lowest glucose levels linked to a heightened risk of death.

Significant differences in death rates between patients on insulin and those taking tablets are also flagged up.

But there could be various explanations for this, experts noted.

Patients taking insulin-based treatments have been urged not to stop taking their medication as a result of the Cardiff University study, which is published in The Lancet.

Changing treatments

Using data from GPs, the team identified 27,965 patients with type 2 diabetes whose treatment had been intensified to include two oral blood glucose lowering agents - metformin and sulphonylurea.

A further 20,005 patients who had been moved on to treatment which included insulin were added to the study.

Patients whose HbA1c levels - the proportion of red blood cells with glucose attached to them - were around 7.5%, ran the lowest risk of dying from any cause.

For both groups this risk went up by more than half if levels dropped to 6.4%, the lowest levels recorded. For those with the highest levels the risk of death increased by nearly 80%.

But the risks appeared to be particularly pronounced among those on the insulin-based regimen than those on the combined treatment.

Irrespective of whether their HbA1c levels were low or high, there were 2,834 deaths in the insulin-taking group between 1986 and 2008, nearly 50% more than in the combined group.

'Don't stop'

The authors acknowledged there could be various factors associated with this, such as these being older patients with more health problems, who perhaps had had diabetes for a longer period of time. They also make reference to a possible link between use of insulin and cancer progression that had been reported in a different study.

"Whether intensification of glucose control with insulin therapy alone further heightens risk of death in patients with diabetes needs further investigation and assessment of the overall risk balance," wrote lead author Dr Craig Currie.

"Low and high mean HbA1c values were associated with increased all-cause mortality and cardiac events. If confirmed, diabetes guidelines might need revision to include a minimum HbA1c value."

Dr Iain Frame, head of research at Diabetes UK, described the study as "potentially important" but stressed it had limitations.

"It is not clear what the causes of death were from the results reported. Furthermore, when it comes to the suggestion made in this research that insulin could increase the risk of death, we must consider important factors such as age, the duration of their diabetes and how the participants managed their condition.

"It is crucial to remember that blood glucose targets should always be agreed by the person with diabetes and their healthcare team according to individual needs and not according to a blanket set of rules."

While people would be able to manage their condition for a period with diet, exercise and even tablets, many would eventually have to move on to insulin, he noted.

"We would advise people with type 2 diabetes who use insulin not to stop taking their medication. However, if they are worried about blood glucose targets, they should discuss this with their healthcare team."

Magnetic activity in brain 'diagnoses stress disorder'

A one-minute test appears to diagnose post-traumatic stress disorder with an accuracy of 90%.

The test measures the tiny magnetic fluctuations that occur as groups of neurons fire in synchrony, even when subjects are not thinking of anything.

These "synchronous neural interactions" have already been shown to distinguish signals from subjects with a range of disorders including Alzheimer's.

The latest work is reported in the Journal of Neural Engineering.

The brain's signals are effectively a symphony of electrical impulses, which in turn drive tiny magnetic fields.

Researchers have measured and mapped these fields, in a pursuit known as magnetoencephalography, since the late 1960s. It has already been used to diagnose tinnitus, and can even predict when people will make mistakes.

Apostolos Georgopoulos, at the University of Minnesota in the US, developed the synchronous neural interactions (SNI) approach as a means to mathematically untangle the myriad signals that magnetoencephalography produces.

In 2007, he led a group that showed that SNI signals can distinguish between subjects with multiple sclerosis, Alzheimer's disease, schizophrenia, Sjögren's syndrome, and chronic alcoholism.

One to watch

Professor Georgopoulos and his colleagues have now used the approach to assess its accuracy in diagnosing post-traumatic stress disorder (PTSD).

The team recruited 74 military veterans who had already been diagnosed with PTSD alongside 250 members of the public.

The subjects were asked simply to stare at a dot for up to a minute while the magnetic signals were collected - a measure of the brain "at rest".

This is in contrast to preliminary results reported in 2009 that functional magnetic resonance imaging, or fMRI, may be useful in diagnosing post-traumatic stress disorder.

In that work, subjects were exposed to images of combat situations.

The SNI approach proved 90% accurate in discerning which subjects had PTSD.

"The excellent results obtained offer major promise for the usefulness of the SNI test for differential diagnosis," the team wrote, "as well as for monitoring disease progression and for evaluating the effects of psychological and/or drug treatment."

Dr Neil Greenberg, a researcher in military psychiatry at King's College London, expressed doubt that a clinical test of this sort solves the principal challenge in diagnosis.

"The main challenge with PTSD - with the military, emergency services, or journalists - isn't diagnosing it," he told BBC News.

"It's with getting people who might have the condition to come forward and have an assessment and treatment.

The approach teases out signals from neurons firing together

"If someone could go out and point a device at a hundred people and tell which of them would actually benefit from treatment but aren't going to come forward and get help, that would be useful."

He added that, in current practice, a treatment programme would in any case be decided through the same lengthy behavioural questionnaires that are used to diagnose the disorder.

Rajendra Morey of Duke University, a researcher into the neurological basis of PTSD and other disorders, said that such reluctance to come forward is endemic across medicine, adding that the SNI approach "has a lot of merit" in the formal study of brain disorders.

"We already have behavioural measures to diagnose PTSD, but I think the strength here is that it can be done very rapidly and objectively," he told BBC News.

"The sort of stigma that PTSD is some kind of weakness may be overcome to some extent by establishing, by further confirming, that it's really changes in the brain and that we have objective measures of these changes.

"I think it's something that the scientific community, especially in PTSD and mental health research, will watch closely."

Cord blood stem cell transplant hopes lifted

A technique which may eventually remove the need for matched bone marrow transplants has been used in humans for the first time.

It is hoped that "master cells" taken from umbilical cords could be used on any patient without rejection.

The latest advance, published in the journal Nature Medicine, greatly multiplies the tiny number of cells from the cord ready for a transplant.

UK charity Leukaemia Research said this could be the "holy grail" for doctors.

Aggressive treatment

The current system of bone marrow transplantation helps patients who have diseases, such as leukaemia, which affect the stem cells in their bone marrow where new blood cells are grown.

Their own bone marrow cells are killed off by aggressive treatment and cells from a matched donor are introduced in their place.

However, a matching donor cannot always be found, despite extensive donor registries held by organisations such as the Anthony Nolan Bone Marrow Trust and, even with a carefully matched donor, there is still a risk that the patient's body will reject the new cells.

Cells extracted from umbilical cords could overcome these problems - they do not have the characteristics which would normally trigger immune rejection, so it is likely that cells from a single baby's cord could be used in any patient, without the need for matching.

However, there is one big disadvantage - there are not enough cells in a single cord to meet the needs of an adult patient.

Scientists have been looking for ways to either combine the cells from more than one baby, or to "expand" the cell numbers in the laboratory.

The second of these options is far from straightforward - simply allowing the stem cells to divide and increase in the laboratory means that many of the resulting extra cells will be simple blood cells, which do not have the ability to produce new cells themselves.

Quick to work

Researchers at the Fred Hutchinson Cancer Research Center in Seattle believe they may have found a way.

They manipulated a "signalling pathway" in the stem cells to trigger an increase in numbers without losing their stem cell status.

After success in laboratory animals, these cells were used in human patients, and the researchers found that they were accepted by the body more quickly and contributed more to the rebuilding of functioning bone marrow than "non-expanded" cord blood transplants.

Dr David Grant, Scientific Director of charity Leukaemia Research said: "The holy grail is to have an 'off the peg' source of unlimited numbers of 'neutral' stem cells which can be given to any patient safe in the knowledge that they will not cause the very difficult 'graft versus host' problems that lead to rejection and often the death of the patient.

"This is a promising development towards this because the concern has been that once stem cells start 'growing' they lose their stem cell properties and progress to ordinary blood cells with a very limited lifespan."

Henny Braund, chief executive of The Anthony Nolan Trust, said the potential for umbilical cord blood was "huge", and that the charity had already imported well over 250 units of umbilical cord blood.

"Sadly in the UK, despite our scientific expertise, umbilical cord blood is still very much an untapped resource and we are only able to collect and store a tiny amount of the cords we need.

"We really need a properly resourced UK cord blood collection programme.

"Further investment is crucial if we are to capitalise on this amazing resource and save more lives."

Cancer drugs 'treat' aggressive childhood brain tumours

Aggressive childhood brain tumours could be treatable with a novel combination of two existing cancer drugs, a study suggests.

Researchers led by the Institute of Cancer Research (ICR) examined 90 tumours from children and found two new genetic abnormalities in nine of them.

They were then able to kill these abnormal tumours, in laboratory tests, by combining the two existing drugs.

But one expert says the findings remain "far off being applicable to patients".

In the UK, about 400 children are diagnosed with brain tumours every year.

The research, published in the journal Clinical Cancer Research, brought together scientists from the UK, France, Portugal, Brazil and America.

The abnormal tumours - known as glioblastomas, aggressive and often fatal cancers of the brain's glial cells - contained too many copies of the EGFR gene and mutations of the gene the scientists say have never before been found in children.

They tried to block the EGFR gene with a drug, erlotinib (Tarceva), used in clinical trials to treat adult glioblastomas, but identified a molecule specific to the children's cells - platelet-derived growth factor receptor (PGFR) - that was making it ineffective.

But when they combined erlotinib with a drug, imatinib (Glivec), they hoped would block the PGFR molecules, they killed a significant number of the cancer cells.

Dr Chris Jones, who led the research, said it proved "that cancers may look the same, but it is only when you get down to the genetic level that you can truly understand them and devise treatments".

Professor Geoff Pilkington, of the Brainstrust charity, said the research, though fascinating, was at too early a stage to turn into a treatment for patients.

"This sort of twin therapy is a good thing to consider for the future," he said.

Bur he added: "The cells of the brain seem to be unusually resistant to anything thrown at them."

Biological cells reveal brain chemistry secrets

Scientists have developed biological cells that can give insight into the chemistry of the brain.

The cells, which change colour when exposed to specific chemicals, have been used to show how a class of schizophrenia drug works.

The researchers hope they will also help shed light on how many other drugs work on the brain.

The study, by the University of California - San Diego, is published in Nature Neuroscience.

Schizophrenia is most commonly associated with symptoms such as delusions and hallucinations.

But people with the illness also struggle to sustain attention or recall information.

A class of drugs called atypical neuroleptics has become commonly prescribed, in part because they seem to improve these problems.                                                           

However, the way they altered brain chemistry was uncertain.

It was known that the drugs trigger the release of a large amount of a chemical called acetylcholine, which enables brain cells to communicate with each other.

However, the drugs have also been shown to hobble a receptor on the surface of the receiving cell, which would effectively block the message.

The San Diego team designed biological cells - called CNiFERs - which changed colour when acetylcholine latched onto this particular class of receptors - an event scientists have not previously been able to detect in a living brain.

They implanted the cells into rat brains, then stimulated a deeper part of the brain in a way known to release acetylcholine nearby.

In response, CNiFERs changed colour - proving that they were working.

They then gave the rats one of two atypical neuroleptics. In both cases the drug severely depressed the response from the CNiFERs.

This suggested that the drugs' receptor-blocking action over-rides the increase they trigger in acetylcholine.

Researcher Professor David Kleinfeld said the new cells had great potential to reveal the mysteries of chemical action in the brain.

He said: "It's a world of signalling between cells that we were blind to before."

The researchers say they are already working to redesign CNiFERS so they can detect the activity of other types of receptors as well.

Paul Corry, of the mental health charity Rethink, said: "This study shows the value of mental health research.

"It is eliciting new information that could lead to the development of more effective drug treatments for schizophrenia, which have fewer of the debilitating side-effects associated with even the most modern atypical medicines.

"That in itself would benefit millions of people around the world.

"But the research also offers a new technique for understanding the workings of the brain that could also be developed for use across broad areas of medicine.

"We really do need to recognise that mental health research is starved of funds compared to other areas of medicine and recognise also that much of it takes place at the frontiers of our understanding which means that results from it could have far-reaching applications."