Category: Health and Medicine

Sciencebase news and views on health and medicine, including posts on Covid-19, bird flu, cancer, asthma, obesity, vaccines, and much more.

Vocal cords and asthma

A diagnosis of exercise-induced bronchospasm – asthma – is commonly given to patients who present with cough, breathlessness and wheeziness after exertion despite being otherwise physically fit. An alternative explanation to bronchial (airways) constriction was discussed on BBC Radio 4’s Inside Health this week on which they suggested that vocal cord dysfunction might be to blame as the vocal folds close over the airway in susceptible individuals.

Thus, physiotherapy and breathing exercises rather than asthma medication might be a better intervention for many sufferers (unless they also have underlying asthma). It does rather suggest that asthma might be being over-diagnosed. It also hints that yoga, singing and other techniques that teach better posture and breathing may actually have a genuine mode of action if they can control the constriction of one’s vocal folds.

Intriguingly, a quick PubMed search turned up a paper from 1996 on seven elite athletes with psychogenic vocal cord dysfunction who presented with apparent exercise-induced asthma that was nothing of the sort. The study’s conclusion is that “The mere association of exercise and airway obstruction is not sufficient to establish the diagnosis of asthma.”

That was 1996…why are we only now [six years later at the time of writing] learning about this issue and the potential differential diagnosis for exercise-induced breathing difficulties. If you or your child’s physician offers asthma meds for those after-sport symptoms ask whether vocal cord dysfunction might be to blame.

There is actually no real, definitive test for asthma, peak flow meter before and after inhaled salbutamol seems to be the usual way. However, there is a way to diagnose exercise-induced vocal cord dysfunction using trans-nasal endoscopy.

Vocal cord dysfunction masqueradin… [Am J Respir Crit Care Med. 1996] – PubMed – NCBI.

Tea and crumpets and prostate cancer risk

Earlier this week I criticised the endless studies reporting that tea, sex, coffee can raise and/or lower prostate cancer risk. Well, NHS Choices has waded in with its usual balanced assessment of the work and come to a sensible conclusion:

Men who are tea drinkers should not be alarmed by the results of this study as it has many limitations that cast doubt on the reliability of the findings. However, men should remain alert to the signs and symptoms of prostate and other forms of cancer, regardless of their tea habits.

via 'Tea raises prostate cancer risk' – Health News – NHS Choices.

The site points out that it might just be that men who drink more tea tend to be healthier in other ways and so live longer. Longevity is definitely a risk factor for prostate cancer, certainly you cannot get the disease in your 60s if you died of a heart attack in your 50s…to put it bluntly.

Lycopene and cancer prevention

Over the years there has been a lot of tomato talk, about how lycopene, the red pigment found in this fruit (yes, it’s definitely a fruit, it’s got seeds), could ward off cancer, specifically prostate cancer. It has also been linked to protecting us from cardiovascular disease, per the common discussions about the so-called Mediterranean diet. It is not a panacea and tests and trials have been small-scale. Nevertheless, as with the likes of that other infamous compound, resveratrol found in red wine, researchers are keen to demonstrate a link with their particular natural chemical and disease prevention.

In the first June issue of SpectroscopyNOW I discuss tests on lycopene extracted from tomatoes that seem to show it offers a certain level of protection against liver cancer triggered by nitrosamines, in lab mice at least. Ashwani Koul and his colleagues at Panjab University in Chandigarh, India, have been doing the research with interesting results. I asked Koul about the impetus:

“Since time immemorial, the tomato has formed an integral component of food, both traditional and western form,” he told Sciencebase. “It is used widely as a vegetable and is abundantly used in the preparation of sauces, curry, soup etc. throughout the world. Epidemiological studies indicate that populations consuming high amounts of vegetables including tomato, in their diet have a reduced incidence of several types of cancer.” So that’s the start of it…

“Over the years, lycopene, a nutrient found in tomatoes, has drawn much attraction for its ability to combat several chronic diseases including cancer,” he adds. “Moreover, lycopene being a component of major dietary source (tomato) finds acceptance with the population and its use is also not restricted as is the case with synthetic chemopreventive agents.” Indeed, lycopene is already marketed as a supplement, although specific health claims are not permitted under FDA rules for supplements without additional regulatory approval.

“With the studies planned and in progress we intend to determine the optimum levels of lycopene as a cancer chemopreventive agent, so as to tap its maximum potential,” Koul told me. “Further, we aim to investigate the detailed underlying mechanism of its cancer chemopreventive potential. Such studies would scientifically validate the anticancer abilities of phytonutrients present in vegetables including lycopene.”

You can read the full story on SpectroscopyNOW.

Tomato photo via CC on flickr.

Anti-inflammatory food

Education regarding lifestyle, diet and exercise might be the key to avoiding chronic inflammation. “A comprehensive food-based strategy for reducing inflammation and thus reducing the incidence and severity of a large array of chronic illnesses and declining health is supported by a large and growing volume of scientific investigations,” US researchers suggest.

They outline the wide range of compounds present in a huge number of foods and nutrients all of which might, if taken as part of a balanced approach to diet that avoids the conventional exercise-free junk food lifestyle, might just help society side step the growing epidemic of chronic inflammation and the diseases it brings.

Anti-inflammatory Response to Certain Foods.

The health benefits of giving, joining in and having a plan

Helping others, joining in and having some kind of life plan or at least goals, aspirations and ambitions seem to make for enhanced mental health. Certainly, it’s a better strategy than popping supplements and introspection. There is even some scientific evidence that spending money on others, rather than yourself, makes you happier, as does laughter, singing, socialising, taking part, all apparently good for the immune system in ways we are only starting to understand. There is even growing evidence that making plans somehow keeps the mind and body healthy.

How far such notions go is a matter for further research. For instance, it is probably stretching it to say that being active and having a positive outlook can ward off cancer, Alzheimer’s or other diseases. However, it might be that the immune boost one gets from being mentally and physically active and engaging with other people offers protection that is simply not available through popping pills or navel gazing…

Indeed, writing in 2010, Alzheimer’s researcher Patricia Boyle demonstrated that: “Greater purpose in life is associated with a reduced risk of AD and MCI in community-dwelling older persons.” Reference. Meanwhile, here’s how to buy happiness.

Ultrasound blasts prostate cancer

Today, the BBC is reporting another medical “breakthrough” – high-intensity focused ultrasound (HIFU) for treating prostate cancer as an adjunct or even alternative to radiotherapy, chemo, and invasive surgery. Ultrasound can be highly focused, essentially boiling the diseased tissue rather than damaging surrounding tissues with the risk of incontinence and impotence associated with invasive surgery.

It’s good news for prostate cancer sufferers, but as far as I am aware HIFU has been used to treat prostate cancer since at least 1989. The technique was first developed in France by Inserm scientists and others and the Ablatherm HIFU was first marketed for the disease in 2000. The first “commercial” treatments were in 1993 and there have been tens of thousands since.

NHS Choices reported on HIFU back in 2009 when there was a flurry of interest from the media in this “new” technique for treating prostate cancer. It says:

“Current NICE guidance advises that the evidence supports…HIFU for prostate cancer, provided that monitoring, audit and clinical governance of any procedures are carried out. It advises that longer-term effects on survival and quality of life are unknown, and that doctors should therefore ensure that patients understand these uncertainties.”

The BBC itself has reported on HIFU for prostate cancer before, there was a report in February 2011 hailing the benefits of the “new” treatment. As an aside, they refer to the urethra as the “water pipe” in that report, how quaint. So, why is this news on the BBC Radio 4 Today program today, could it be that the editors and journalists on the show simply hadn’t heard of HIFU before and so assumed it was new when a press release came from Lancet Oncology touting the benefits over surgery (in a 41-patient trial)? You can almost bet your gland on it.

Regardless, it is all positive stuff, but it does beggar the question as to why the technique, more than two decades in the development, is only now reaching public ears…

More red meat risk analysis

NHS Choices finally published its critique of the Harvard red meat research that had the tabloids screaming that meat kills earlier this week. I provided some commentary on Sciencebase soon after. Anyway, this is what NHS Choices concludes:

“This study had several strengths including its size, long follow-up period and detailed and repeated assessments of people’s meat intake. It also adjusted the results for other factors that might affect risk of mortality.”

However, the site also points out that the study was based on questionnaires. “…relying on participants to self-report factors, such as their meat intake through questionnaires, introduces the possibility of error, although the questionnaires were validated,” it adds.

One major concern, however, is that the participants in the study were mainly white health professionals, so the results may not be relatable to other populations.

NHS Choices adds that: “This study cannot prove that regular consumption of red meat ‘kills’.” The site points out that despite what vegans and others often claim, “Red meat is a good source of protein and certain nutrients such as iron, some vitamins and zinc.”

On the basis of a suspected increase in bowel cancer risk, the UK’s Department of Health advises adults who eat high levels of red and processed meat to reduce their intake to no more than 70 grams a day. I’d add to that the same kind of guideline they offer for alcohol consumption – moderation and not every day. Steak and ale every day is not going to be good for you…you can just tell, really, can’t you?

Carbon emissions and reproductive health

Is there a link between carbon emissions in the developing world and reproductive health?

High carbon emissions correlate with poorer reproductive health among women in nine countries of 74 assessed, according to US researchers. Conversely, economic development seems to have no significant association with female reproductive health.

FangHsun Wei and Vijayan Pillai of the University of Texas, in Arlington, explain that women’s reproductive health plays a crucial role in sustaining population health. This, they say, is because as women’s health improves they are more likely to make healthy choices and promote the health and well-being of their children.

The World Health Organization define reproductive health as “a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity, reproductive health addresses the reproductive processes, functions and system at all stages of life”. Moreover, the term reproductive health also implies that a person is “able to have a responsible, satisfying and safe sex life and that they have the capability to reproduce and the freedom to decide if, when and how often to do so.”

The researchers have looked at data on reproductive health, economic status and environmental factors for 74 developing nations across the globe in sub-Saharan Africa, The Americas, Eastern Europe and Central Asia, the Middle East, East Asia and the Pacific nations and South Asia. Carbon dioxide emissions from the burning of fossil fuels and cement production are used as a proxy of environmental degradation given that the activities that drive such emissions also generate pollutant issues at a more local level.

The team used statistical regression analysis to look at the effects of various causative factors on selected and well-measured outcomes: reproductive rights (reproductive rights scale), economic development (GNI per capita), social development (improved water source) and environmental development (carbon dioxide emissions) are independent variables, and reproductive health (RRI) is the dependent variable.

“The results of this study have implications for improving the conditions that are conducive to reproductive health of mothers and infants in developing countries,” the team asserts. They point out that the correlation between carbon dioxide emissions and poor reproductive health in the developing world (despite CO2 emissions being far lower per capita than in the US) implies that participation in global initiatives to develop renewable and sustainable energy sources and avoiding the use of fossil fuels will ultimately have beneficial effects on reproductive health as well.

Research Blogging IconFangHsun Wei, & Vijayan K. Pillai (2012). Environmental quality and reproductive health in developing countries Int. J. Sustainable Society, 5 (2), 146-159

Losing weight is easier than you think

The tabloids were recently full of nonsense about metabolic rate, diets, weight loss, obesity…hold on…when are they not full of nonsense? The latest story claimed that it’s twice as hard to lose weight than current guidelines suggest. Is it? Here’s what the NHS has to say on the matter.

It also offers advice on the best way to lose weight and suggests that shedding just 5% of your body mass, if you’re overweight can reduce high blood pressure and lower your risk of developing type 2 diabetes.

The NHS also links out to the NIH online weight simulator tool, which allows you to input your age, gender and weight and then calculates how many calories you need to cut from your diet in order to achieve a target weight loss. It is actually a research tool and includes no advice on diet or exercise, so it’s useful but not a substitute for personal medical advice on diet and weight loss.

Is antioxidant luteolin an anticancer super-nutrient?

A flavonoid compound found in fruit and vegetables, luteolin, was recently hailed as an anticancer supernutrient by the tabloid media. Aside from the fact that over-dosing on antioxidants could be detrimental to one’s front-line immune response to pathogens, the research was purely laboratory based and said nothing about whether or not luteolin might actually prevent bowel cancer. The compound has the chemical name 2-(3,4-dihydroxyphenyl)- 5,7-dihydroxy-4-chromenone and in the laboratory shows activity as an inhibitor of phosphodiesterase enzymes as well as blocking interleukin 6.

NHS Choices, as ever, dissects the study, saying that the research may have homed in on the specific signalling pathway through which luteolin can kill bowel cancer cells in the laboratory. The study did not investigate whether upping one’s intake of luteolin-rich foods would have any effect on bowel cancer risk.

The lab study is an essential first step to understanding whether luteolin or more likely a chemical cousin might eventually be developed as an anticancer drug, although this is preliminary, fundamental molecular biology not clinical testing and animal studies for initial testing of such a compound are still a long way off. A drug might never emerge from this research.

Luteolin is found in celery, green pepper, thyme, dandelion, perilla, chamomile tea, carrots, olive oil, peppermint, rosemary, navel oranges, and oregano, fruit rinds, woody barks, clover blossom and ragweed pollen. It has also been isolated from Salvia tomentosa.

NHS Choices emphasises that, “It is important to remember that this study used pure luteolin, and not dietary sources of the compound. The effect of dietary luteolin on cancer is not clear from this research.” Of course, one has to presume that eating a diverse mixture of fresh fruit and vegetables as part of a well-balanced diet (whatever that means) is to be encouraged nevertheless.