Monthly Archives: August 2012

My Holidays.

I will be away for the next 2 weeks for my son, Clive’s, wedding. For some crazy reason they have decided to get married in Melbourne!. The weather forecast is for rain and a maximum of 11 degrees..  I do not know if I will survive it. (the cold, I mean). If I don’t return, you will know it is because I have turned into a block of Ice.

As usual, I will be away for the last 2 weeks of December, and the 1 st week of Jan. Plan your visits to me around those dates, and make sure you have enough scripts to tide you over. Please no desperate phone calls when I am up the coast lazing around the pool, asking for scripts because you have run out. I know menopause is to blame for many things, but I am giving you ample warning 🙂

Menopause and Osteoporosis/Heart disease

Climacteric. 2012 Aug 8. [Epub ahead of print]

Severity of menopausal symptoms and cardiovascular and osteoporosis risk factors.

Pérez JA, Palacios S, Chavida F, Pérez M.
Source

Primary Health Centre Guadalajara-Sur , Guadalajara.
Abstract

Objectives To assess whether the severity of menopausal symptoms is related to increased cardiovascular and osteoporosis risk factors, and to determine whether women with more severe menopausal symptoms present a greater percentage of osteoporosis disease Conclusions Women with more severe menopausal symptoms had a greater prevalence of cardiovascular and osteoporosis disease risk factors and suffered more from osteoporosis disease compared to those who had milder or no menopausal symptoms.

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Chocolate – the good news.

Having a healthy lifestyle does not have to be boring and dull – eating oats and going to the gym. A Cochrane report (Cochrane centre is considered the most authoritative source in the world) showed that eating dark chocolate lowered blood pressure. Hooray!!. My wife loves chocolate,  so this gives her the all clear,  free of guilt.

Is drinking grapefruit juice bad for your hearing?

It could be. Grapefruit juice contains many good vitamins but it also has the ability to inadvertently increase the potency of many drugs, sometimes to alarming levels. We all know mixing certain medications is not a good idea as they can have an additive or even a synergic effect (the effect of the combined drugs is greater than just adding the two together). However, grapefruit juice can have the same effect as mixing different medications.

When we take medication, certain enzymes (CYP 3A4) in our body break down the compounds, so they can get filtered out of our bodies in the appropriate manner. Some of the medication is absorbed before the enzyme has a chance to break it down, and is able to have an effect. If the medication doesn’t break down at the expected rate, the amount of medication that is absorbed can alter. This means you may not get the right dose. Grapefruit juice contains chemicals called furanocoumarins which chemically bond to CYP 3A4, stopping them from working as effectively as they should. This can lead to much larger active doses of medication entering our system, effectively like overdosing your medication. A study reported that Lovastatin levels in the blood increased by 1500% when taken with grapefruit juice! If these drugs have an ototoxic effect, they can be extremely damaging to your ears and hearing.

We all have slightly different levels of CYP 3A4 in our stomachs, some people have more than others. This information is more important if you have high levels of CYP 3A4 in your stomach and are taking medications. In this case always consistently take the same amount of grapefruit juice at the same time of day so your Doctor can monitor your progress and manage your medication effectively to how your body absorbs it, or not drink grapefruit juice at all. If you have very low levels of CYP 3A4, it may not make much difference at all.
Of all the citrus fruits, grapefruit juice is the only one that contains furamocoumarins, but it is present whether the juice is fresh, pulped or even concentrated. Drinking grapefruit juice is cumulative, so even a little bit every day, or a lot every few days can be dangerous. If you have any queries about your medications please ask your Doctor or the Pharmacist to check if there is a known grapefruit interaction.
Medications that have a known ototoxic effect and are known to interact with grapefruit juice include:
Angiotensin-2 receptor antagonists (eg Losartan)
Anti-arrhytmics (eg Propafenone)
Anti-convulsant drugs (eg Carbamazepine)
Anti fungal antibiotics (eg Itraconazole)
Anti Neoplastics (eg Vinblastine)
Cardiac Glycosides (eg Digoxin)

Orange juice is looking like a much more attractive and safer option to start your day with.

Dr Clive Holloway
Audiologist

If you want to know more about hearing problems, check “www.sunshinehearing.com.au” Yes, that is my son, Clive.

Weight gain – is it due to Fructose?

4 August 2012, 6.43am AEST
What role does fructose have in weight gain?

Sucrose or sugar has two components – glucose and fructose. Glucose is present in virtually all naturally-occurring sweet foods and also exists as starch (although in a different chemical form, so it doesn’t taste sweet). Fructose occurs naturally in fruit, honey and some vegetables. But the main sources…
Author

Chris Forbes-Ewan
Senior Nutritionist at Defence Science and Technology Organisation

Disclosure Statement

In 2003 Chris Forbes-Ewan received funding from: National Health and Medical Research Council (NHMRC) for his contribution to establishing the Nutrient Reference Values for Australia and New Zealand. His contribution was to assist in determination of the Estimated Energy Requirements.

The Conversation provides independent analysis and commentary from academics and researchers.

We are funded by CSIRO, Melbourne, Monash, RMIT, UTS, UWA, Deakin, Flinders, Griffith, La Trobe, Murdoch, QUT, Swinburne, UniSA, UTAS, UWS and VU.

Sucrose or sugar has two components – glucose and fructose. Glucose is present in virtually all naturally-occurring sweet foods and also exists as starch (although in a different chemical form, so it doesn’t taste sweet). Fructose occurs naturally in fruit, honey and some vegetables. But the main sources of fructose in the typical western diet are processed foods and beverages that contain added sugar derived from sugar cane or sugar beet.

In some countries, notably the United States, a sweetener known as high-fructose corn syrup (HFCS) is used to sweeten many processed foods, but HFCS is not a common source of fructose in the Australian diet.

Ingested fructose is treated differently to glucose following digestion and absorption into the body. While glucose is readily transported around the body to where it’s needed as an energy source, fructose is metabolised almost exclusively in the liver.

Many studies have shown that feeding animals (such as rats and mice) high-fructose diets leads to increased body weight, higher levels of blood lipids and blood pressure, and other components of metabolic syndrome (a condition that pre-disposes to several diseases, including heart disease and type 2 diabetes).

Fructose occurs naturally in fruit, honey, some vegetables and in sugar, which is derived from sugar cane or sugar beet. tinyfroglet/Flickr

There’s also good evidence that fructose is addictive in rats, perhaps in a similar way to cocaine. As a result, there’s speculation that the fructose component of sugar may be one of the major driving forces behind the current epidemics of obesity and type 2 diabetes in humans.

The proponent of this concept with the highest profile is a US professor of paediatrics, Dr Robert Lustig, who argues that fructose is “alcohol without the ‘buzz’”, that is, it’s addictive in people, toxic and equally harmful as alcohol.

Lustig hypothesises that consumption of added fructose (that is, other than that occurring in fruit) at virtually any level promotes metabolic syndrome, leading to obesity, type 2 diabetes and increased risk of heart disease. As a result, he argues, fructose consumption is the cause of the obesity epidemic, and 35 million deaths occur annually worldwide because of it.

But how strong is the evidence for this “fructose hypothesis”, and how much credence should we give to the claim that fructose is the sole cause of most of our health problems?

Although it would be wonderful if there were a simple solution (such as avoiding all sources of added fructose) to the epidemics of obesity and type 2 diabetes that are sweeping the world, the evidence implicating fructose as the sole cause is weak, to say the least.There’s overwhelming support for the belief that high intakes of fructose are harmful to human health, but the evidence is, at best, equivocal that low or even moderate intakes of fructose are harmful, in either normal weight people or in those who are overweight or obese.

One of the problems with the fructose hypothesis is that much of the evidence comes from animal studies, especially those involving rats. But people are not rats, and it’s not appropriate to assume that similar effects will be seen in humans. Animal studies can only allow working hypotheses to be proposed, hypotheses that must then be subjected to rigorous testing.

In relation to the likelihood of sucrose (and therefore fructose) addiction occurring in humans, for instance, a review published in 2009 concluded there was “no support from the human literature for the hypothesis that sucrose may be physically addictive”, despite strong evidence for addiction in rats and mice.

Another effect that’s been claimed for fructose is that it’s less satiating than glucose, that is, fructose doesn’t make you feel as full, so you overeat. But, as applies to most of the claimed adverse effects of fructose on human health, the evidence for this is, at best, equivocal.

The consumption of fructose in liquid form is associated with higher energy intake and increased body weight. Brad Herman

One 2009 review found that fructose was less satiating (so its consumption was associated with overeating), while another published in the same year concluded that “the case for fructose being less satiating than glucose … is not compelling.”

The most recent (2012) scientific review that addressed this issue concluded that “Fructose does not seem to cause weight gain when it is substituted for other carbohydrates in diets providing similar calories. Free fructose at high doses that provided excess calories modestly increased body weight, an effect that may be due to the extra calories rather than the fructose.” In short, if you overeat, you can expect to put on weight!

But there is evidence that, when taken in liquid form (such as soft drinks or fruit juices), consumption of fructose is associated with higher energy intake, increased body weight, and the onset of metabolic syndrome.

So what are we to make of all this? At this relatively early stage in our attempts to elucidate the role fructose may play in the epidemics of obesity and type 2 diabetes, it’s probably safe to conclude that very high fructose intake can have serious and adverse metabolic effects in humans. But there’s no convincing evidence to support the claim that fructose is the sole cause of these epidemics, or that fructose intake at moderate doses is harmful.

Prostate Cancer/Mammograms

I have just added a comprehensive report on the harm that prostate cancer testing does to men. I strongly suggest those interested read it – under the Male Hormone Section of this web site – Prostate cancer. This is a carbon copy of the breastscreening (mammograms) issue – the testing leads to overdiagnosis, overtreatment, and long term harm. The statistics quoted by those promoting these tests, are misleading because they are now labelling breast and prostate changes “cancer” when in fact htey are pseudo-cancers, and would not lead to any harm to the person. Their results look good because they appear to be “curing” cancers which in fact did not need curing. Read the research in case I am being accused of bias. Women often tell me that they had breast cancer, but that it has been cured by mastectomy and radiation. I wonder how many of them did not actually need the mastectomy and radiation, and would have been better off without it. But how can I tell them that they underwent all that pain and trauma for nothing.

Please note I am only referring to healthy, well women/men who go in for screening and come out with a cancer diagnosis and treatment and all that entails. I am not referring to people who get obvious cancer and will need appropriate treatment.

I cannot stress how important an issue this is for all of us and we owe it to ourselves to be informed and aware of the evidence.

Health Tip

The three-minute work-desk stretch

Believe it or not, sitting is harder on your body than standing – especially if you sit in the same position for long periods. So take time out at least every hour for this three-minute, total-body stretch. You’ll work better and your body will feel better too.

Either print out these easy exercises or bookmark this page so you can refer to these exercises whenever you need a mini-break. Practise these moves often and this three-minute routine will soon become a part of your workday.
Hands and arms

Finger curl:
Make a fist with each hand, but keep your thumbs out straight. Pull your fingers up your palm until your fingertips touch the base of your fingers. Release.

Wrist stretch:
Place one hand on the fingers of the other. Slowly bend your wrist down until you feel a stretch. Hold for 3 – 5 seconds and relax. Repeat 3 times. Then repeat bending upwards.

Arm stretch:
Sit at your desk with your elbows on the table. Keeping your palms together, slowly lower your wrists to the table until you feel a stretch. Hold for 5 – 7 seconds. Repeat 3 times.
Neck and shoulders

Shrug:
Pull your shoulders up to your ears, hold for 3 – 5 seconds, and relax. Repeat 2 – 3 times.

Neck incline:
Sitting or standing with a straight back, relax your head to the right, trying to touch your ear to your shoulder, being careful not to raise your shoulder. Hold for 3 – 5 seconds and raise your head. Repeat on right side, then forward. Repeat the sequence until tension is released.
Back

Side stretch:
Sitting in your chair with your feet flat on the floor, reach your arms above your head and interlace your fingers. Press your arms as far back as you can and hold them a moment. Slowly lean to one side, hold for a few seconds and then return to an upright position. Repeat on the other side.

Back curl:
Holding your right shin just below your knee, lift your leg off the floor while curling your back forward. Try to touch your nose to your knee. Hold for a moment. Lower your leg and repeat on the left side.

Open chest stretch:
Sitting at the edge of your chair, pull your arms behind you and interlace your fingers with your palms facing your back. Leaning slightly forward, lift your arms up and try to place them on the chair back. Pull your shoulders down, away from your ears, and take a few deep breaths before releasing.
Feet and legs

Ankle curl:

Lift your left leg straight in front of you. Flex and point your foot, so your toes stretch up to the ceiling, then straighten out. Repeat 2 – 3 times, then rotate your foot in circles, clockwise 3 times, then anticlockwise. Repeat with your right leg.

Quality of life and HRT

Many women are so scared of hrt that they suffer for years unnecessarily. We now know that the risks are small,and can be minimized if it is done correctly with the right hormones. More and more studies from eminent scientists,like the one below, are appearing.
Climacteric. 2012 Jun;15(3):213-6.

Quality of life and the role of menopausal hormone therapy.

Source

Ichilov Hospital, Tel Aviv, Israel.

Abstract

The quality of life of countless menopausal women world-wide has been significantly diminished following the sensationalist reporting of the Women’s Health Initiative (WHI) and the resulting 50% or more decline in the use of hormone replacement therapy (HRT) over the subsequent 10 years. Quality of life is difficult to measure as there are so many contributing factors and a large number of different instruments, some of which assess general health and only a few which specifically include symptoms related to menopause. HRT improves quality of life of symptomatic menopausal women and some studies of the effects of HRT provide reliable evidence on quality of life other than reduction in vasomotor symptoms. Until there is a better understanding of the minimal risks of HRT for the majority of women, too many will continue to suffer a reduced quality of life unnecessarily.

More on Breast screening

An article published in the British Medical Journal (BMJ) today says a US charity “overstates the benefit of mammography and ignores harms altogether.” The charity’s questionable claim is that early detection is the key to surviving breast cancer and to support this, it cites a five-year survival rate…
Authors
Fiona Margaret Fidler

Senior Research Fellow of Australian Centre of Excellence for Risk Analysis (ACERA) at University of Melbourne
Bonnie Claire Wintle
PhD student at University of Melbourne

Disclosure Statement

Fiona Margaret Fidler has previously received funding from the ARC.

Bonnie Claire Wintle does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

The Conversation provides independent analysis and commentary from academics and researchers.

We are funded by CSIRO, Melbourne, Monash, RMIT, UTS, UWA, Deakin, Flinders, Griffith, La Trobe, Murdoch, QUT, Swinburne, UniSA, UTAS, UWS and VU.

The University of Melbourne Founding Partner of The Conversation.
6ccxk5v4-1343957168 Basic statistical literacy is important for communicating and understanding medical risks. Janet Ramsden

An article published in the British Medical Journal (BMJ) today says a US charity “overstates the benefit of mammography and ignores harms altogether.” The charity’s questionable claim is that early detection is the key to surviving breast cancer and to support this, it cites a five-year survival rate of 98% when breast cancer is caught early, and 23% when it’s not.

We’re not interested in judging the charity’s actions or intentions but would like discuss the importance of statistical literacy in communicating medical risks.

There are two critical claims in the argument presented by the experts in the BMJ report – that routine breast screening results in high false positive diagnoses and that five-year survival rates are biased. It’s necessary to understand them both to be able to judge whether the statistics quoted by the charity are misleading.
False positive diagnoses

What would you think if your routine mammogram came back positive? Most women would justifiably fear the worst. And what you probably won’t be considering is the high false positive rate of screening tests (9%) combined with the low probability of breast cancer in the female population (about 1%, but note that this is different to lifetime risk, which is about one in nine). This combination means a lot of false diagnoses.

The probability that a woman who returns a positive mammogram actually has breast cancer. Factoring in the low probability of breast cancer and the high rate of false alarms, only one in ten women with a positive mammogram in this scenario will have breast cancer. Fidler and Wintle, adapted from Gigerenzer at al, 2008

It’s important to remember that we are talking here about the outcomes of widespread screening in the absence of well-defined risk factors – not the screening of women in specific high-risk groups, defined by factors associated with age, genetic predisposition, exposure and lifestyle.

The statistics would be different for high-risk groups because the base rate of the disease will be different (higher). In the case of routine screening, however, positive diagnoses need to be treated with caution, and serious action should not be taken on the results of a screening diagnosis alone.
Five-year survival statistics

Imagine a group of women all diagnosed with breast cancer at the same time. The proportion of those still alive after five years is called the five-year survival rate. It’s calculated by dividing the number of women diagnosed with breast cancer still alive after five years, by the total number of women diagnosed with breast cancer.

Now imagine a random group of women, not defined by breast cancer diagnosis. The proportion of those who die within a 12-month period of breast cancer is called the annual mortality rate. It’s calculated by dividing the number of women who die of breast cancer within a 12-month period, by the number of women in the random group.

It’s often claimed that the five-year survival rate gives an inflated, or overly optimistic, picture of survival compared to mortality rates. This optimistic picture of survival comes from two sources of bias.
Lead-time bias

The first of these sources is known as lead-time bias. Imagine a woman who is diagnosed with breast cancer at age 67. She dies three years later at age 70. The five-year survival rate in this case is 0% – she survived only three years, not five.

Now imagine this same woman was instead diagnosed with breast cancer as a result of routine screening at age 60. She still dies at 70, but because she has survived ten years (rather than three), the five-year survival rate is 100%. Although the mortality age is exactly the same, the five-year survival rate is dramatically different.

The combination of the high false positive rate of screening tests combined with the low base rate of breast cancer in the female population means a lot of false alarms and diagnoses. U.S. Navy/Wikimedia Commons

Over-diagnosis bias

The other source of bias is called over-diagnosis. Over-diagnosis is not the same as false diagnosis, which we mentioned at the start of this piece. Rather, over-diagnosis refers to non-progressive cancers and “pseudo-disease”.

Pseudo-diseases are abnormalities that meet the technical definition of cancer, but are unlikely to ever cause symptoms, let alone death. Non-progressive cancers are unlikely to cause death within the five-year survival rate time frame.

How much over-diagnosis inflates the five-year survival rate depends on the type of cancer. For breast cancer, some estimates of pseudo-disease are as high as one-in-four of all diagnoses made by screening. For these women, a positive diagnosis may mean unnecessary chemotherapy, radiation or surgery.
Alternative measures

Critics of the five-year survival rate make two recommendations. The first is to report absolute risks (the risk of developing a disease over a period of time) rather than relative risks (compares risk in two different groups of people).

The BMJ article reports the absolute risk of a woman in her 50s dying from breast cancer over the next ten years as being reduced from 0.53% to 0.46% with mammography – a difference of 0.07 percentage points. This compares with the 25% relative risk reduction that is often cited in support of screening.

The second recommendation is to report risks in “natural frequencies” – in real numbers, like ten out of 1,000 (as shown in our figure above) rather than percentages and probabilities. There’s good empirical evidence suggesting the presentation of absolute risks in natural frequencies is a much clearer way to communicate medical risks to doctors and patients alike.

Improved statistical literacy about breast cancer screening is vital because it means that people can make informed decisions about screening and seek a second opinion if a test comes back positive.
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