Less invasive cancer surgery is safe and effective

In most cancer patients, axillary-lymph-node dissection (ALND) involves the removal of most of the lymph nodes in the underarm region to improve the chances of survuval, but sometimes it causes damages to the patients' arm and shoulder.

American scientists found that sentinel-lymph-node surgery (SLN), a less invasive technique that only removes the sentinel nodes, the ones closest to the breast, is safe and effective.


5,611 American women whose breast cancer did not appear to have spread to their lymph nodes were recruited to assess their differences in survival rates between the 2 types of surgery. Half of the patients had ALND surgery to remove all of the lymph nodes in the underarm area, while the other half had SLN surgery to remove the sentinel lymph nodes only. Patients were tracked over the next eight years.

The researchers found no significant differences in the patients' survival rates between the two groups. Patients who underwent the SLN procedure were less likely to experience arm problems or lymphoedema (chronic swelling of the arm). The authors concluded that "SLN surgery alone with no further ALND is an appropriate, safe, and effective therapy for breast cancer patients with clinically negative lymph nodes" and that SLN surgery "represents the next major step in reducing the extent of surgical procedures to treat breast cancer".

An accompanying comment said that the paper "vindicates contemporary practice of SLN biopsy and provides support for a reduction in extent of axillary surgery for most patients with breast cancer".


Source: Sentinel-lymph-node resection compared with conventional axillary-lymph-node dissection in clinically node-negative patients with breast cancer: overall survival findings from the NSABP B-32 randomised phase 3 trial. Lancet Oncology, 11(10):927 - 933. Published Online: 21 September 2010 (f/t via Athens)

Is glucosamine effective in reducing OA joint pain?

A BMJ study found that 2 popular supplements, glucosamine, chondroitin and their combination are no better than placebo at reducing joint pain.

The study, funded by the Swiss National Science Foundation, was a meta-analysis based on 10 randomised controlled trials with more than 3800 patients with hip or knee osteoarthritis treated with either glucosamine, chondroitin or both, followed up for 1 to 36 months. The outcome measures were pain intensity and joint structure. The analysis of data was by network meta-analysis, a relatively new statistical technique.

The researchers found that all these 2 supplements have been prescribed by GPs and rheumatologists and used widely by patients for treating osteoarthritis (OA), their study showed that glucosamine, chondroitin and their combination do not have a useful clinical effect in treating osteoarthritis. They wrote "we believe it unlikely that future trials will show a clinically relevant benefit of any of the evaluated preparations".

Critics say that the study results may be biased by the heterogeneity of the varying studies included and the network meta-analysis it used to do the calculation. Furthermore, the small size of the trials could also have large effect on the overall results.

Some patients, based on their own experience, are convinced that these supplemnets are beneficial and have written to the BMJ in response to the findings, some doctors pointed out that glucosamine has 2 different formulation, the favourable response of glucosamine to knee OA involves glucosamine sulphate not hydrochloride and that many of the recommendations of use of glucosamine are on knee OA not hip, but the study included both knee and hip OA in the analysis.

It was also noted that the conclusion of the study on the efficacy of glucosamine on knee OA is questionable because it does not include the data of the LEGS trial which investigates glucosamine sulphate in knee OA, the study is yet to be completed.

Source:

1). Wandel S, Jüni P, Tendal B et al. Effects of glucosamine, chondroitin, or placebo in patients with osteoarthritis of hip or knee: network meta-analysis. BMJ 2010; 341:c4675 ( f/t via Athens)

2). The Long-term Evaluation of Glucosamine Sulphate Study (LEGS) - study to be completed in October 2011

Revised UK guidelines for melanoma 2010

According to Cancer Research UK, the latest statistics show that 5,697 cases of malignant melanoma were diagnosed in women and 4,975 in men in the UK in 2007. If melanoma is diagnosed early, the survival statistics are very good.

Many guidelines have been drawn up by various groups and professional bodies to promote good standards of care. Last month, the British Journal of Dermatology published revised consensus guidelines for treatment and a brief overview of epidemiology, diagnosis, investigation and follow up.

The guidelines were drawn up by a multidisciplinary working party with representatives from various groups or organisations in the UK. Levels of evidence to support the guidelines are given, but the authors said that care should be individualized wherever appropriate. Where no level of evidence is quoted, it is regarded as a consensus statement, represented level IV.

Summary of the guidelines:

• Melanoma patients who must be referred from the local skin cancer multidisciplinary team to specialist skin cancer multidisciplinary team
• Recommendations for local skin cancer team record keeping of clinical features
• Recommendations for sscreening and surveillance of high-risk individuals
• Requirements for microscopy of melanoma
• Surgical wider excision margins for primary melanoma
• Staging investigations for melanoma
• Recommendations for the management of clinically node-negative patients
• Recommendations for locoregional recurrent melanoma
• Recommendations for metastatic disease
• Pregnancy, oral contraceptives and HRT
• Follow up of melanoma patients

Source:
"Revised U.K. guidelines for the management of cutaneous melanoma 2010". Published in the British Journal of Dermatology, August 2010 Vol. 163, PP.238-256. Free full text

Low-carb diet rich in meat may may cause higher health risks

Studies show that a low-carbohydrate diet produces weight loss and improves some cardiovascular risk factors, but there has been concern about the Atkin-type low-carb diet that is based on animal fat and animal protein.

Harvard reserachers examined 2 types of low-carb diets in relation to long-term health impact. They examined the data of 2 prospective cohort studies involving 85,168 women for 26 years and 44,548 men 20 yaers on a low-carbohydrate diet, either an animal-based or a vegetable-based low-carbohydrate diet. Diet was assessed via a questionnaire.

The researchers found that animal-based low-carb diets were associated with higher all-cause mortality in both men and women. A vegetable-based low-carbohydrate diet was associated with lower all-cause and cardiovascular disease mortality rates. They said the results suggest that the health effects of a low-carb diet may depend on the type of protein and fat. The mixed effects on lipid profiles may have been due to the varying amount of plant or animal fat consumed in low-carb diets.

An accompanying editorial cautioned the interpretation of this study saying that it "addresses a critical, unresolved public health question of diet but cannot satisfy us with a definitive answer", a large- scale randomised clinical trial with meaningful clinical endpoints is needed.

Source: Low-Carbohydrate Diets and All-Cause and Cause-Specific Mortality - Two Cohort Studies. Annals of Internal Medicine. September 7, 2010 vol. 153 no. 5 289-298 (f/t via Athens)

Should I take vitamin B supplements for mild memory problems?

Oxford scientists investigated the effects of vitamin B on brain atropy ( the loss of neurones and their connections) in people with mild memory problems. Studies have found that high levels of homocysteine (tHcy), an amino acid in the blood, affect the rate of brain atropy and that raised levels of tHcy increase the risk of Alzheimer's disease.

168 elderly people with mild cognitive impairment but not taking anti-dementia drugs were recruited in the Oxford area. Both the volunteers and researchers were unaware of the treatment received, either high dose of vitamin B tablets ( a combination of folic acid, B12 and B6) or placebo pills for a 2 year period.

The researchers found that taking B vitamins for 24 months led to brain shrinkage and the rate of shrinkage in the treatment group was 30% less than the placebo group. They concluded that a simple and safe treatment can slow down the rate of brain atropy in people with mild cognitive impairment. The study was published in PLoS One, a peer-reviewed journal. A study published in 2008 in JAMA showed conflicting results.

Critics say that this is well-conducted randomised controlled trial with promising results. However the evidence did not show brain shinkage may lead to improvement in symptoms or that the B vitamins can prevent Alzheimer's disease, but warrant more research.

Source: David Smith A, Smith SM, de Jager CA et al. Homocysteine-Lowering by B Vitamins Slows the Rate of Accelerated Brain Atrophy in Mild Cognitive Impairment: A Randomized Controlled Trial. PLoS One 5(9): e12244

The Avandia scandal

An investigation by the BMJ published this week calls for the withdrawal of the daibetes drug, Avandia, immediately from the market because of the concerns that it may increase the risk of myocardial infarction and the paucity of good evidence to support its use.

Rosiglitazone, also known as Avandia, was GSK's second biggest selling drug, introduced in 1999 and is widely used to lower blood glucose levels in patients with type 2 diabetes. It was approved by the EMA in 2000 despite concerns over its safety.

In 2007, several studies found Avandia having harmful effects and issued serious health warnings. The researchers questioned why Avandia is still available on the market and why physicians would prescribe it to diabetic patients when there are other drugs without these side effects. They called for Avandia to be withdrawn from the market. Since then, the sales of Avandia fell sharply.

The BMJ investigators found that in July, the UK Commission on Human Medicines advised the MHRA to withdraw Avandia as the risks of Rosiglitazone outweigh its benefits. This has raised a lot of questions about the quality of the data used in the studies and the lack of trial results made available to the public. The investigators also ask why the regulators accept such poor evidence on benefit and safety, why patients in the UK and Europe are not make aware of the concerns about this drug and whether the current regulatory body is doing its job properly. They said that doctors are advising that no new patients shoud use this drug, existing diabetic patients should review their options and those at high risk of heart disease should stop taking it.

In the accompanying editorial, the authors said that clinicians had focused on the wrong endpoint and lost sight of the main reason for treating this disease, "which is not to reduce glycaemia but to prevent complications". They went on to say that clinicians need to be "absolutely certain that the long term treatment for type 2 diabetes are not causing the harm they are meant to prevent" and should insist on robust evidence of benefits and harms.

Professor Freemantle noted in the accompanying commentary that the Avandia studies were hindered by inadequate data due to high levels of loss to follow-up. He wrote "In order to learn from our mistakes, we must improve the quality of safety data from clincal trials on all new healthcare interventions, not just antidiabetic drugs" and an overhall in the standards of regulatory trials is needed.


Sources : free f/t
Rosiglitazone: what went wrong? BMJ 2010; 341:c4848 (Published 6 September 2010) Editorial - Licensing drugs for diabetes BMJ 2010; 341:c4805 (Published 6 September 2010)
Commentary: What can we learn from the continuing regulatory focus on the thiazolidinediones?BMJ 2010; 341:c4812 (Published 6 September 2010)

Is chocolate good for the heart?

Previous studies have shown that chocolate can reduce blood presure, a strong risk factor for heart failure. Harvard reserachers carried out a large prospective cohort study, including more than 39,000 Swedish women, investigating if chocolate intake is linked to the risk of heart failure.


The data were obtained from a questionnaire on health and lifestyle including details about diet and chocolate intake. After 9 years follow up, the researchers found that women who ate 1 - 2 servings a week or 1 -3 servings a month had lower risk of hear failure than those who ate 3 or more servings a week. They suggest that flavenoids in chocolate may have a beneficial effect on cardiovascular risk factor.


Critics said that the study relied on participants self-reporting of their chocolate intake, it is also unclear how much chocolate was consumed in one "serving". Although this was a large study, it is felt that the evidence was not strong enough to tell if chocolate reduces the risk of heart failure. Furthermore, flavenoids in chocolate can be found in fruit and vegetables.


Source: Mostofsky E, Levitan EB, Wolk A, et al. Chocolate Intake and Incidence of Heart Failure: A Population-Based, Prospective Study of Middle-Aged and Elderly Women. Circulation: Heart failure 2010; Published online before print August 16 ( f/t via Athens)

Diabetes drug linked to higher heart attack risk

Avandia and competitor drug, Actos, are commonly used diabetes drugs. Avandia has been found having harmful effects since 2007 while Actos seems safer apparently.

2 studies published last week reported serious health warnings. One study, published in June 28 issue of JAMA, reviewed the data of 227,000 patients takng either Avandia or Actos, found that Avandia increased the risk of heart attack, stroke or death by 17%.

The second study, published in the Archive of Internal Medicine, analysed 56 clinical trials involving 35,000 patients confirmed these findings. The reserachers questioned why Avandia is still available on the market and why physicians would prescribe it to diabetics when there are other drugs without these side effects. They called for Avandia to be withdrawn from the market.

However, some doctors said that the evidence is inconclusive.

Source:
1). David Juurlink. "Rosiglitazone and the Case for Safety Over Certainty". JAMA. 2010;304(4):(doi:10.1001/jama.2010.954). free f/t

2). Steven Nissen; Kathy Wolski. "An Updated Meta-analysis of Risk for Myocardial Infarction and Cardiovascular Mortality". Arch Intern Med. 2010;170(14), free f/t

Does statin use reduce prostate cancer recurrence?

Statins is a common treatment to lower cholesterol but a study, published online in June 28 in Cancer, found that men taking statins before their prostate surgery were less likely to show signs of the cancer recurring.

The study reviewed the data of 1319 men who had prostatectomy and took statins when they had their operation and showed that they had a 30% lower risk of PSA recurrence compared to those not taking statins. The greater the dose of statins taken, the less likely the cancer was to reappear.

The researchers said if other studies support their findings, a RCT of statins is warranted. However, critics say that the statin users differed significantly from non-users at presentation, eg they were older and had higher BMI that might affect the association between the statin use and risk for biochemical recurrence, also previous studies had mixed findings.

Another study, published in the Journal of Clinical Oncology, with 691 men underwent radiotherapy, showed a significant association between statin use and decreased biochemical recurrence.

Source:
1). Hamilton RJ, Banez LL, Aronson WJ et al. "Results from the Shared Equal Access Regional Cancer Hospital (SEARCH) Database". Cancer, [Early online publication] June 28 2010

2). "Statin Use and Risk of Prostate Cancer Recurrence in Men Treated With Radiation Therapy". Journal of Clinical Oncology, Vol 28, No 16 (June 1), 2010: pp. 2653-2659
Early Release 10.1200/JCO.2009.27.3003 on April 26 2010

Do B vitamins reduce lung cancer risk?

Smoking is the major risk factor for lung cancer, according to a new study published in JAMA, higher levels of vitamin B6 and methionine in the blood was associated with lower risk of lung cancer.

This was a large scale IARC study with 520,000 volunteers across Europe, part of the EPIC cohort. Blood samples were taken from both the case group and the control group and the amount of B6 and methionine measured.

The researchers found that there was a lower risk of lung cancer with a higher level of B6 and methionine whether they were smokers or non-smokers. Overall, people with above average levels of B6 and methionine had 50% reduction in the risk of developing lung cancer than those with below average levels.

Critics say that the blood samples were taken on only one occasion and a cohort study cannot prove a cause and effect for a reduced risk of lung cancer for B6. Furthermore, B6 and methionine are found in meat and potatoes, but it was unknown whether eating more of this food would make a difference to the risk of developing lung cancer because a lower level of these substances in the blood may be due to poor absorption.

Source: Johansson M, Relton C, Magne Ueland P, et al. "Serum B Vitamin Levels and Risk of Lung Cancer". JAMA 2010; 303: 2377-2385

Racial gaps in lung cancer surgery

A new study published in JAMA found that black patients newly diagnosed with lung cancer were less inclined to have surgery than whites because they did not connect well with their doctors.

Researchers analysed data from 386 lung cancer patients in Carolina and found that only 55% of black patients had surgery compared to 66% of white patients. They found that many black patients misunderstood their prognosis or did not feel comfortable enough to discuss with their doctors treatment options and outcomes. Black patients were also less likely to have other sources of support.

The authors said that there are many barriers to improving the disparities but doctors and hospitals can work on the negative perceptions of patient-physician communications and spend more time with patients about their treatment options.

Source: "Factors Associated With Decisions to Undergo Surgery Among Patients With Newly Diagnosed Early-Stage Lung Cancer". JAMA, 2010; 303 (23): 2368-2376

Are HRT patches safer than pills?

A large study including 75,000 women suggests that low-dose HRT patches may be safer than tablets in terms of stroke risk, but the risk increases significantly with high dose patches.

The findings are based on a nested case-control study drawing data from the General Practice Research Database in the UK. Researchers compare a group of women who have stroke ( case group) to a group who do not ( control group) and found that women using low-dose HRT patches had no increased risk of stroke compared with those who had not used HRT patches, however, using high-dose patches had an increased risk of 89% compared with non-use.

Researchers concluded that low-dose HRT patches may be a safer alternative to oral HRT, although these results alone cannot prove causation, "this study should encourage further research on the importance of the route of administration to define the role of transdermal oestrogens in the therapeutic arsenal for the treatment of menopausal symptoms."

Critics say that this study could affect prescribing practice but it only looked at stroke risk while HRT is assocaited with other risks such as breast cancer, venous thromboembolism and heart disease. The study was published in the BMJ.

Source: Renoux C, Dell’Aniello S, Garbe E and Suissa S. Transdermal and oral hormone replacement therapy and the risk of stroke: a nested case-control study. BMJ 2010;340:c2519, (Published June 3 2010) full text via Athens

Brush your teeth twice a day could lower cardiovascular risk

According to a new research by University College London, published in the BMJ, people who brushed their twice a day had a lower risk of heart disease compared with those with less frequent toothbrushing.


The researchers analysed data from more than 11,000 adults who took part in the Scottish Health Survey between 1995 and 2003. Each survey was linked to hospital admissions and deaths, followed up until 2007. They found that people who rarely brushed their teeth had a 70% greater risk of cardiovascular disease than those who brushed their teeth twice a day. However they said that the study did not prove a cause and effect association between oral health and cardiovascular disease.


Previous studies have established a link between gum disease and cardiovascular risk, but the researchers said this is the first study to show an association between self-reported toothbrushing and incident cardiovascular disease and suggest "a possible role of poor oral hygiene in the risk of cardiovascular disease via systemic inflammation." They noted that further studies are needed to confirm whether the observed association is causal or merely a risk marker.


Source: Toothbrushing, inflammation, and risk of cardiovascular disease: results from Scottish Health Survey. BMJ 2010;340:c2451

Statins side effects quantified

A new study, published in the BMJ, to quantify the unintended effects of statins according to type, dose, and duration of use found that statin use was associated with increased risks of serious liver dysfunction, acute renal failure, moderate or serious myopathy ( muscle weakness) and cataracts.

Researchers examined the medical records of over 2 million patients who registered at GP practices in England and Wales, the patients were monitored over a period of 6 years. They found that Simvastatin was the most prescribed statin and the side effects are already known. Eestimates of the absolute risks were also provided : for 10,000 people, there would be 17 extra cases of kidney failure, 252 cataracts, 65 liver problems and 32 myopathy. The adverse effects were similar across the statin types for each outcome except liver dysfunction where fluvastatin was associated with the highest risks.

The accompanying editorial says that the benefits of statins seem to outweigh the risks. It is suggested that patients should not change their medication.

Source: Hippisley-Cox J, and C Coupland. Unintended effects of statins in men and women in England and Wales: population based cohort study using the QResearch database. BMJ 2010;340:c2197 ( f/t via Athens)

Processed meat increased heart disease risk

A new systematic review and meta-analysis of 20 studies involving more than 1.2 millions people from 10 countries found that processed meat such as bacon, salami, sausages, hot dogs and processed deli, was linked to increased risk of heart disease and diabetes, but red meat was not.

Participants were followed up to 18 years and found that those who ate 50 gram a day of processed red meat had 42% higher risk of heart disease and 19% higher risk of type 2 diabetes than those who did not eat processed red meat.

Researchers said that the processed meat contain much higher salt and preservatives ( rather than fats) than unprocessed meat and this could explain the difference. They found the same even when lifestyle factors were taken into account and suggested that these types of meats should be studied separately in future research.

Source: "Red and Processed Meat Consumption and Risk of Incident Coronary Heart Disease, Stroke, and Diabetes Mellitus. A Systematic Review and Meta-Analysis". Circulation. 2010 Published online before print May 17, 2010 ( f/t via Athens)

Medical journals on Twitter

Twitter started as social networking or microblogging that combines blogging and instant messaging. Users can create a short message of up to 140 characters ( called “tweets”), send and receive updates from any computer or mobile devices with Internet access.

Tweets are instantly available to the “followers”, so it is a quick way of communicating with a group of people. Twitter has become a major distributor of timely information, particularly in the area of breaking news. The 1st reports of the crash of a US jetliner into the Hudson River in January 2009 were sent by witnesses on Twitter.

Many medical journals and organisations have started to use Twitter to disseminate information quickly to large groups of people.

For example - "Are probiotic drinks good for children? Looking at research we agree they may have small benefit for some illnesses " - was a tweet by NHS Choices

BMJ, The Lancet, NEJM, JAMA and many others also use Twitter to provide Table of Contents (TOC) service with links to the most current articles.

If you use Twitter to share medical information and opinion, beware of the issues of confidentiality.

Eating nuts may reduce cholesterol

Previous studies have shown that nut consumption reduces the risk of coronary heart disease, a new systematic review published in the May 10 issue of Archives of Internal Medicine found that diets rich in nuts were associated with reduced total cholesterol and bad cholesterol.


Researchers pooled data from 25 trials conducted in 7 countries that compared a control group to an experimental group assigned to consume nuts. An average of 67 grams of nuts per day were consumed over 3 to 8 weeks, they found that total cholesterol was reduced by 5.1% and bad cholesterol by 7.4%, but there was a lesser effect on reducing the cholesterol levels of people with higher BMIs.


Critics noted that the overall population of the studies was relatively small, the study results might have been affected by the different diets used in different studies. The experimental diet lasted only 3 to 8 weeks long, so it is not clear what effect it would have over the longer term. It is also unclear whether the reductions in cholesterol and LDL-cholesterol would be enough to lower the risk of coronary heart disease. Although nuts may reduce cholesterol, they are high in saturated fats and should be eaten in moderation.


Source: "Nut Consumption and Blood Lipid Levels - A Pooled Analysis of 25 Intervention Trials". Arch Intern Med. 2010;170(9):821-827. ( f/t via Athens)

Working overtime is bad for your heart

According to a study of 6000 British civil servants published online in the European Heart Journal, people who regularly work overtime have higher risk of developing coronary heart disease than those who do not.

The study involved over 6000 men and women aged between 39 and 61 who did not have heart disease and worked full time at the start of the study. Researchers found those who worked 3 to 4 hours of overtime a day had 60% higher risk of developing heart disease, overtime work was also associated with lower HDL cholesterol ( good cholesterol).

Experts said the study highlights the importance of work-life balance but note that the link was only found in association with 3-4 hours oertime a day. The lead researcher said more research is needed.

Source: Overtime work and incident coronary heart disease: the Whitehall II prospective cohort study. Eur Heart J (2010). First published online: May 11, 2010 ( f/t via Athens)

Vitamin A does not reduce maternal mortality

A new study, (Obaapa VitaA) in Ghana showed that vitamin A supplementation to women of child-bearing age in poor nations does not reduce maternal death rates. The Ghana findings contradicted previous results from a trial in Nepal which showed a 44% decrease in maternal death among women given vitamin A.

The researchers conducted a randomised and double-blind trial in 7 districts in the Brong Ahafo Region of Ghana. Participants were randomly assigned to vitamin A supplement or placebo capsule orally every week. They found that there was no statistically significant difference between the intervention and the control groups.

The author, Professor B Kirkwood at The London School of Hygiene and Tropical Medicine concluded that "the results of this trial in Ghana vindicate the decision not to change safe motherhood policy immediately after the Nepal trial."

Source: Betty R Kirkwood et al. Effect of vitamin A supplementation in women of reproductive age on maternal survival in Ghana (ObaapaVitA): a cluster-randomised, placebo-controlled trial. The Lancet, 2010; 375(9726):1640-1649 ( f/t via Athens)

Virgin olive oil changes gene activity

Previous studies have shown a Mediterranean diet is associated with lower risks of all major diseases, but a small size study published in the open access journal BMC Genomics shed new light on how virgin olive oil influences certain genes that promote inflammation and can lead to heart disease.

Spanish researchers gave 20 volunteers with metabolic syndrome 2 breakfasts containing virgin olive oil with either high or low levels of phenols randomly on 2 separate days with a week apart. Both researchers and participants did not know who had received which breakfast. The researchers then measured the changes in the gene expression after the breakfasts and found that 39 genes are involved in the inflammation process (that has a role in the build-up of fatty deposits in the blood vessels ) and 35 of them were less active after eating the high-phenol virgin olive oil.

The researchers concluded that the study could partly explain why the risk in cardiovascular disease is reduced in Mediterranean countries where the diet is rich in virgin oliver oil.

Critics say that this study helps our understanding of the effect of olive oil on gene activity but it is difficult to confirm that the changes in gene activity is responsible for the reduction in risk of cardiovascular disease. The small size of the study, all participants with metabolic syndrome, gene expression after one meal and the lack of follow up for long-term outcomes are just some of the limitations that may affect the results of the study.

Source : Antonio Camargo, Juan Ruano, Juan M Fernandez, Laurence D Parnell, Anabel Jimenez, Monica Santos-Gonzalez, Carmen Marin, Pablo Perez-Martinez, Marino Uceda, Jose Lopez-Miranda and Francisco Perez-Jimenez. "Gene expression changes in mononuclear cells from patients with metabolic syndrome after acute intake of phenol-rich virgin olive oil". BMC Genomics, 2010