Electronic interference with hospital tracking chips

According to a study published in JAMA, radio frequency identification tags (RFID) used in critical care units in hospitals such as syringe staplers and blood bags, can interfere with life-saving equipment and machines.

Dutch researchers conducted 123 tests of 2 types of RFID tags on 41 medical devices in an unused room at a university medical centre intensive care unit not involving patients and found 34 cases of electromagnetic interferences, 22 of which would have been life-threatening.

An accompanying editorial said the study will need to be conducted with patients present in order to get a true understanding of the problem. However, the co-author of the study argued that these tests could endanger the patients.

Source: "Electromagnetic Interference From Radio Frequency Identification Inducing Potentially Hazardous Incidents in Critical Care Medical Equipment" JAMA. 2008;299(24):2884-2890. (Full text via Athens)

Anaesthetics may enhance pain

According to a newspaper, scientists carried out a laboratory study in mice and discovered that although general anaesthetics suppress the central nervous system and make people unaware of pain during surgery, some general anaesthetics can cause inflammation in other parts of the body causing some patients high levels of pain when they wake up.

The study has identified one protein that is associated with the activation of pain pathways by some general anaesthetics and this knowledge may be helpful to develop better general anaesthetics in the long term.

Source: "General anesthetics activate a nociceptive ion channel to enhance pain and inflammation". Proc Natl Acad Sci USA 2008; Jun 23 [Epub ahead of print]

A new technique offers new hope to patients with small malignant lung tumours

A newspaper reported that a new technique called radiofrequency ablation has given hope to patients with small malignant lung tumours that could not be treated with sugery, radiotherapy or chemotherapy.

Researchers said it has produced good response rates and is safe to warrant further study after they recruited 106 patients for the study and found that the new technique successfully treated 88% of tumours and about 50% of patients who had primary lung cancer were alive after two years. The study was funded by Angiodynamics which made the radiofrequency ablation device.


Source: "Response to radiofrequency ablation of pulmonary tumours: a prospective, intention-to-treat, multicentre clinical trial (the RAPTURE study)." Lancet Oncology 2008; Jun 18 [Epub ahead of print]

Lifestyle changes may slow prostate cancer

Newspapers reported a small pilot study of 31 men with very low risk prostate cancer that looked at the effects of lifestyle changes on the activity of different genes in prostate tissue.

The participants did not want immediate surgery, hormone therapy, or radiotherapy but agreed to change comprehensive lifestyle including good diet and exercise. By the end of the study, they had reduced BMI, blood pressure, waist size and blood lipids. 48 genes were found more active and 453 genes less active after the intervention. Some of them are related to tumour formation.

Researchers concluded that intensive nutritional and lifestyle changes may change gene activity in the prostate and suggest larger studies to confirm their findings.

Source : "Changes in prostate gene expression in men undergoing an intensive nutrition and lifestyle intervention." Proc Natl Acad Sci 2008; [Published online June 16]

4 cups of tea a day cuts heart disease risk

Newspapers reported a review of several studies on tea consumption and its effects that found drinking more than three cups of tea a day cuts the risk of heart attack due to the natural plant antioxidants, polyphenols, in tea. The researcher also found that adding milk to tea made no difference to the effect of tea. The study was funded by the Tea Advisory Panel and the Tea Council.

Although the evidence indicates a positive role for tea in human health, critics say that there are many risk factors that contribute to the development of heart disease, people should not rely on drinking tea for protection from heart attacks.

Source: "Black tea and health." Nutrition Bulletin 2008; 33 91-101

Higher heart attack risk in men with vitamin D deficiency

News source reported that researchers at Harvard analyzed medical records and blood samples from 454 men who had a heart attack or disease and compared them to 900 men who had no history of cardiovascular disease.

They found that men with a vitamin D deficiency (15 nanograms or less per ml of blood) had a higher risk of heart attack than those with a sufficient amount of vitamin D (30 nanograms per ml of blood or more). They concluded "the results further support an important role for vitamin D in myocardial infarction risk"

Source :"25-Hydroxyvitamin D and Risk of Myocardial Infarction in Men - A Prospective Study"
Archieve of Internal Medicine. 2008;168(11):1174-1180.

Red yeast rice extract may be good for the heart

Newspapers reported that a large randomised placebo-controlled trial of 5000 patients showed that the extract of Chinese red yeast rice, XZK, that gives Peking duck its red colour, reduces bad cholesterol that subsequently lowers cardiovascular events in Chinese people who have already experienced a heart attack.

Critics say that although the study provides good evidence of the beneficial effect of the extract, the finding is not surprising because one of the cholesterol-lowering drugs, lovastatin, was originally extracted from yeast rice. They also say that people who are concerned about their risk of heart attack or their cholesterol levels should talk to their GP, who may prescribe them a statin.

Source: "Effect of Xuezhikang, an Extract From Red Yeast Chinese Rice, on Coronary Events in a Chinese Population With Previous Myocardial Infarction." American J of Cardiology 2008; Apr 11 [Epub ahead of print]

Regular use of painkillers could cut Alzheimer's risk

A few newspapers reported a study that has found regular use of ibuprofen, aspirin and other painkillers known as NSAIDs reduces the risk of developing the Alzheimer's disease. Doctors warn that people should not take over-the-counter pain remedies to ward off dementia as there are side effects. The finding is based on a review of six studies involved almost 14,000 people.

Researchers concluded that NSAID use reduced the risk of Alzheimer’s disease. However, they did not find that a sub-group of NSAIDs, known as the SALAs, more effective than other non-SALAs in preventing the disease. This suggests that all conventional NSAIDs have a similar protective effect in humans.

Critics say this was a review of selected studies and that the risk from bleeding need to be considered against any benefits.

Source: "No advantage of A 42-lowering NSAIDs for prevention of Alzheimer dementia in six pooled cohort studies." Neurology 2008; May 28 [Epub ahead of print]

Anti-hypertension drug types do not influence outcome

Previous studies suggest that the effects of anti-hypertensive drugs might be smaller among elderly people and some guidelines recommend specific types of blood pressure lowering treatment for particular age groups.

According to the BMJ, a new meta-analyses of 31 trials with more than 190,000 participants "showed no clear difference between age groups in the effects of lowering blood pressure or any difference between the effects of the drug classes on major cardiovascular events, .... also showed no difference in effects between the two age groups for the outcome of major cardiovascular events".

Source: "Effects of different regimens to lower blood pressure on major cardiovascular events in older and younger adults: meta-analysis of randomised trials -Blood Pressure Lowering Treatment Trialists’ Collaboration" BMJ 2008;336:1121-1123 ( free f/t)

Regular exercises reduce cancer death risk in men

Newspapers reported on a prospective cohort study of more than 40,000 Swedish men that found those who exercised moderately for at least 60 minutes a day reduced their risk of cancer, also in men who have cancer, 30 minutes a day of moderate exercise improved their chances of survival by 33%.

The researchers said the findings ‘may have major public health implications in the prevention and treatment of malignancies’ but the results require confirmation.

Critics say the study did not take into account the effect of diet that can influence their risk of cancer and it is possible that the men who exercised more also had healthier diets.

Source: "Association of physical activity with cancer incidence, mortality, and survival: a population-based study of men" British Journal of Cancer (2008) 98, 1864-1869.

Gum disease link to cancer risk

The BBC reports - Men with a history of periodontal (gum) disease were 14% more likely to develop cancer than those without. This is based on a prospective cohort study that analysed data for more than 48,000 male health professionals who had not had cancer prior to 1986 and who responded to questionnaires about periodontal disease.


Researchers concluded that "periodontal disease is associated with a small, but significant, increase in overall cancer risk" and that this increase in risk exists in men who had never smoked, but they said that "any recommendations for prevention of cancer based on these findings are premature" and further studies are needed to clarify whether periodontal disease itself causes the increase in cancer or whether it indicates some other factors.


Critics say the study included only male professionals, the results may not apply to other groups of people.


Source: "Periodontal disease, tooth loss, and cancer risk in male health professionals: a prospective cohort study." Lancet Oncology 2008; May 6 [Epub ahead of print]

Music's healing and sedative effects in ICU patients

An interesting article from the New York Times.

Dr C Conrad, a senior surgical resident at Harvard with a doctorate in music philosophy, and colleagues carried out a simple study involving 10 ICU patients. Just after the sedation was lifted, 5 were given gentle piano music for 1 hour while 5 heard nothing.

They found that those patients listening to music showed reduced BP and heart rate, less need for pain medication and 20% drop in epinephrine and interleukin-6 ( 2 important stress hormones). They also had a 50% increase in pituitary growth hormone.

Previous research has shown growth hormone generally rises with stress and falls with relaxation, Dr Conrad argued that the growth hormone may reduce the levels of stress hormones that produce inflammation that in turn causes pain and raises BP and heart rate.

Experts said the study suggests a rise in growth hormone may dampen inflammation and stress responses although they did not buy in the proposed mechanism.

Source: "Overture for growth hormone: requiem for interleukin-6?" Critical Care Medicine. 2007 Dec;35(12):2709-13 ( f/t via Athens)

Flavanol-containing cocoa improves diabetics blood flow

A small study funded by Mars Inc. (who also provided the cocoa drinks used in the study) found that three mugs of specially formulated cocoa (containing high levels of flavanols, a type of antioxidant ) a day for a month improved blood flow through the arteries by 30% in diabetics.

They used FMD ( flow-mediated dilation) in the brachial artery (artery in the upper arm) to measure cardiovascular risk - lower FMD has been linked to a greater risk of cardiovascular enents. Researchers concluded that "diets rich in flavanols reverse vascular dysfunction in diabetes" and that cocoa could be used as a treatment to reduce the risk of cardiovascular disease.

Critics warn diabetics should not start eating chocolate to try to reduce their cardiovascular risk because of the high levels of fat and sugar involved, they should eat more fruit and vegetables that also have high levels of the antioxidants.

Source: "Sustained Benefits in Vascular Function Through Flavanol-Containing Cocoa in Medicated Diabetic Patients - A Double-Masked, Randomized, Controlled Trial" J American College of Cardiology, 2008; 51:2141-2149

HRT pills double risk of blood clots

Researchers in France and Glasgow carried out a systematic review and meta-analysis on some studies looking at the risk of venous thromboembolism in women taking hormone replacement therapy HRT) - the BBC reported.


They concluded that "current use of oral oestrogen increases the risk of venous thromboembolism by twofold to threefold" and they said that HRT patch may be safer but further research is needed.


The critics say this new study provides valuable evidence about the size of the risks and gives some idea of the difference between patches and pills, but women should not assume that it is unsafe to take HRT pills or patches are safe.


Source: "Hormone replacement therapy and risk of venous thromboembolism in postmenopausal women: systematic review and meta-analysis" BMJ, published 20 May 2008. Ahead of print ( f/t via Athens)

Biological washing powders do not cause skin irritation

News sources reported that British researchers examined 44 papers about whether enzymes added to detergent washing powders can cause skin reactions and concluded that "biological detergents do not cause skin irritation. They advised that doctors should look beyond laundry detergents for the true cause of eczema, rashes and itches.

Critics said this seems a good advice but the readers should be aware of some of the limitations of this study - the researchers have not described their searching methods, it is not clear if all relevant papers have been looked at, they may fail to detect some publications which could influence their conclusion. The researchers have declared their consultancy fees from Unilever.

Source: "Enzymes, detergents and skin: facts and fantasies" British Journal of Dermatology 158(6): 1177-1181, June 2008

Rosehip for osteoarthritis pain reduction

Researchers conducted a meta-analysis of randomised controlled trials into the use of Rosa canina hip powder treatment compared with placebo for osteoarthritis, reported a newspaper.


They combined and analysed the results from these studies and found that use of Rosa canina reduced pain to about a third compared to the placebo group. People taking the powder were also less likely to use "rescue" medication, ie painkillers.


Critics say the study provides good evidence that rosehip reduces pain associated with osteoarthritis, however it was not set up to determine whether rosehip was better than current treatments.


Source: "Does the hip powder of Rosa canina (rosehip) reduce pain in osteoarthritis patients? – a meta-analysis of randomized controlled trials" Osteoarthritis and Cartilage April 2008 Ahead of print

Unpublished data on herceptin

The Guardian reported a study carried out by New Zealand researchers that investigate whether it is better to use herceptin, a breast cancer drug, alongside the chemotherapy or after it, ie sequential use.

They found that the data of the sequential use of herceptin were not published while data from the women given herceptin alongside their chemotherapy and women in the control group have been fully published in a peer-review journal. When they combined all these results, they found that the effect of herceptin was a third less effective than previously thought.

They concluded that not including these data in the overall assessment of the sequential use of herceptin has led to the treatment recommendation of the drug - a case of publication bias in which drug companies publish only trial results that are favourable.

Source: "Trastuzumab: possible publication bias". Lancet 2008; 371:1646-1648 ( free f/t via Athens)

"Overconfidence as a cause of diagnostic error in medicine"

The May issue of the American Journal of Medicine is dedicated to the understanding and addressing the sensitive issue of diagnostic error. The authors of this particular article conducted an extensive literature review ( with more than 200 references) on the incidence and impact of diagnostic error and examined the possibility that overconfidence contributes to diagnostic error.

The authors noted that the rate of diagnostic error is as high as 15%, "when directly questioned, many clinicians acknowledge that diagnostic errors exist but believe the rate is very low and that any errors are made by others who are less skillful or less careful". The authrs said this reflects overconfidence and complacency that leads to the failure to recognise one's own error.

In the great majority of cases, most diagnosis are correct, but the authors said that very often diagnostic errors are cognitive in nature and arise from those cases that physicians perceive as routine and unchallenging. They failed to recognise the shortcomings that derive from heuristic thinking.

The authors found that many physicians underutilized diagnostic decision-making tools, eg guidelines, and that feedback regarding their errors is also lacking, together with the overconfidence, these have contributed to the high misdiagnosis rates.

Based on the belief that physicians overall are dedicated and well-intentioned, if they were more aware of these factors and their own predisposition to error, they would take steps to reduce their errors, the authors suggest that strategies to address the problem should focus on "improving the physician's calibration between their perception of the case and the actual case".

The authors suggest two approaches to reduce diagnostic error :
1). Improving physician's cognition needs and focusing on making them better thinkers, less subject to biases, and more aware of what they know and do not know.
2). Changing the healthcare environment so that the data on patients, potential diagnoses and any additional information are more accurate and accessible.

Source:"Overconfidence as a Cause of Diagnostic Error in Medicine" American Journal of Medicine 2008;121(5), supplement, S2-S23 (Free f/t)

Beta blockers cost more lives than they saved

For many years, beta blockers have been given routinely to patients undergoing surgery to reduce the risk of heart attcks after operations, but a new study, published in The Lancet, of more than 8000 patients in 23 countries who had surgery has found that those given the drugs double their risk of stroke and a third more likely to die within a month of surgery, the BBC reported.

The lead researcher said although beta blockers had benefits in lowering heart attacks, they were outweighed bythe increase of stroke and death. The study claimed that about 800,000 would have died as a result of doctors giving out the drugs without considering the side effects.

Source: "POISE Study Group. Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomized controlled trial". Lancet 2008. DOI: 10.1016/S0140-6736(08) 60601-7. Ahead of print.

Breastfeeding may protect women against arthritis

According to a new study in the Annals of the Rheumatic Diseases that compared 136 women with rheumatoid arthritis to 544 without the condition, women who had breastfed for 13 months or more were half as likely to develop the disease as those who had never breastfed. The study also found that taking oral contraceptives did not have the same effect.

Experts said previous studies showed that "breastfeeding was a risk factor for developing rheumatoid arthritis in a small group of women soon after giving birth to their first child."

Source: "Breast-feeding, but not oral contraceptives, is associated with a reduced risk of rheumatoid arthritis" Annals of Rheumatic Diseases. Published Online First: 13 May 2008. doi:10.1136/ard.2007.084707 (f/t via Athens)