Wednesday, July 20, 2011

Passive smoking harms hearing of teenagers

I abhor smoking but the report below is sheer nonsense. Working class people are more likely to smoke and have more hearing loss. That is all that they have detected. Yet another crappy study dedicated to condemning sidestream smoke

Teenagers exposed to second-hand smoke are twice as likely to suffer hearing loss, according to research. The findings add to the catalogue of health problems already attributed to second-hand smoke, including increased risks of asthma, heart disease and lung cancer.

Teens exposed to second-hand smoke were more likely to have ‘sensorineural’ hearing loss, which is usually caused by problems with the cochlea, the snail-shaped hearing organ of the inner ear. Scientists think passive smoking affects the blood supply to the area.

The damage caused makes it harder for the person to understand speech and has been linked to poor academic performance and disruptive behaviour in school.

Study author Dr Michael Weitzman, from New York University’s school of medicine, said: ‘It’s the type of hearing loss that usually tends to occur as one gets older, or among children born with congenital deafness.’

Dr Weitzman studied more than 1,500 teenagers aged 12 to 19. They were given extensive hearing tests along with blood tests for the chemical cotinine, a substance produced when the body breaks down nicotine. Those teens exposed to second-hand smoke, as measured by cotinine in their blood, were more likely to have sensorineural hearing loss than those who were not passive smokers.

Results of the study, published in journal Archives of Otolaryngology, which deals with head and neck surgery, also showed that more than four out of five affected were not aware of it.

Study co-author Dr Anil Lalwani, from the department of paediatrics at NYU’s school of medicine, said: ‘More than half of all children in the U.S. are exposed to second-hand smoke, so our finding has huge public health implications.’ He added: ‘Milder hearing loss is not necessarily noticeable. Thus, simply asking someone whether they think they have hearing loss is insufficient.’

Dr Weitzman added: ‘The consequences of mild hearing loss are subtle yet serious. ‘Affected children can have difficulty understanding what is being said in the classroom and become distracted. As a result, they may be labelled as troublemakers or misdiagnosed with ADHD.’


Cholesterol at danger level? Why your doctor could be wrong

By John Naish

Recently I broke a strict personal rule by undergoing a complete private health screening. I’d always rigorously avoided such things, but this was obligatory for work. The battery of tests did the exact thing that I feared. It revealed a potential health problem I had never previously known — nor worried — about. The results showed I have high total cholesterol. Mine is 6.6mmol/l — the target is 5.1.

But I won’t be rushing to my family doctor. That’s because as a health journalist, I’ve seen the way the ‘danger’ threshold for cholesterol has been revised steadily down. Twenty years ago, I would have been well inside the ‘healthy’ category (back then you had to be over 7.6 to be considered unhealthy).

But am I being wise to ignore this warning? A new book by an expert on medical screening strongly vindicates my position. As author Dr H. Gilbert Welch explains: ‘There are many conditions that you can now be labelled with simply because you are on the wrong side of a number, not because you have any symptoms.’

Take diabetes — earlier this month it was revealed the NHS is lowering the threshold for diagnosing type 2 diabetes. As a result, the number of cases could rise by 20 per cent — a massive number. That means thousands more people will be treated for the condition without necessarily having any symptoms.

This is just another example of what Dr Welch describes as an ‘epidemic’ of overdiagnosis. In other words, physical abnormalities that will most likely lie dormant for the rest of our lives are being detected and treated as if you are actually ill.

Dr Welch, who is professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice in Virginia in the U.S., points the finger at our overzealous use of screening — blood tests and scans — which has caused millions of people to believe they are mortally sick when, in fact, they are perfectly healthy.

Worse, it has led countless numbers to take drugs and undergo surgery completely unnecessarily. As a result, they have suffered everything from botched removals of breast lumps to, says Dr Welch, medication-related car crashes.

At the heart of the problem is a change in medical culture over the past three decades. In the past, people didn’t go to the doctor when they were well — they tended to wait until they developed symptoms. And doctors didn’t encourage the healthy to seek care.

But that has changed. ‘Early diagnosis is the goal. People seek care when they are well,’ says Dr Welch.

‘But a patient who has been overdiagnosed cannot benefit from treatment. There’s nothing to be fixed — he or she will neither develop symptoms nor die from their condition — so the treatment is not needed. 'An overdiagnosed patient can only be harmed. And almost all treatments have the potential to do some harm.’

On top of this, there are changes to the thresholds that doctors use to judge if a person is ill or not. Dr Welch points to the example of diabetes. ‘The old rule, from when I was in medical school 30 years ago, was that if you had a blood-sugar level over 140, you had diabetes. But in 1997 experts changed the international definition. 'Now, if you have a reading of more than 126 you have diabetes. That little change turned millions of people into patients.’

As treatment is expanded to people with progressively milder abnormalities such as slightly high blood sugar, their potential to benefit from treatment becomes progressively smaller. But the risk from dangerous side-effects remains much the same.

Another reason for our modern diagnosis epidemic is the fact that we can see more inside the human body — thanks to high-tech machinery such as MRI scanners and CT scanners. They enable doctors to spot things that might be troublesome — even if they aren’t causing trouble and may very well never do so.

When investigators in three separate studies systematically scanned large numbers of healthy people, they found that about 10 per cent have gallstones, even though they have never had symptoms of gall bladder disease. Around 40 per cent show damaged knee cartilage, even though they have never had knee pain. And more than 50 per cent of people who have never had back pain show bulges in the discs in their spine when scanned by MRI.

In another test, in the journal Radiology, when 1,000 people were given total-body CT scans in commercial clinics, even though they had no problem symptoms, 86 per cent had at least one abnormality detected.

So if you go into hospital for broad-scale scanning tests, doctors are almost bound to find something problematic that needs ‘treatment’, even if it wasn’t what they were originally looking for — and even if it is, in fact, never going to cause problems.

The same sort of problem can occur with public-health campaigns such as Britain’s breast-screening programme. The potential dangers of overdiagnosis have even led the president of the Royal College of GPs, Iona Heath, to decline invitations to attend screening sessions.

Advocates of such screening say it prevents diseases, prompts early detection and saves lives — along with millions of pounds of NHS money. But as Dr Heath explains, a study of research evidence by the respected Cochrane Reviews Library ‘suggests that for every 2,000 women invited to screening for ten years, one death from breast cancer will be avoided but that ten women will be overdiagnosed with breast cancer’.

She adds: ‘This overdiagnosis is estimated to result in six extra tumour removals and four extra mastectomies and in 200 women risking significant psychological harm relating to the anxiety triggered by the further investigation of mammographic abnormalities.’

And now we’re entering new realms of disease-seeking, with the advent of DNA testing. Already, numerous commercial enterprises have emerged that will take your DNA and your money, promising to unlock the secrets of your genes.

But while DNA tests can reveal that you have a raised risk of developing one illness and a lower risk of another, ‘for the vast majority of conditions these predictions are inaccurate to the point of being meaningless’, says Dr Welch.

This is because our genes are not our destiny. Factors such as nutrition and harmful exposure to toxins affect human characteristics, even before birth, as does physical and even intellectual activity in childhood. ‘Virtually all of us will have genetic “abnormalities” if we look for them. So the new world of personal genetic testing has the potential to make all of us sick and arguably poses the greatest threat of overdiagnosis of all.’

Dr Welch is careful to say his scepticism is about testing for problems in people who are, to all intents and purposes, entirely well and free from any symptoms. ‘I am not saying that if you have early signs of symptoms of cancer, you shouldn’t go to your doctor,’ he explains.

‘The question is whether your doctor should be screening for cancers when you are well. It can hurt you. It can lead to you being overdiagnosed and treated needlessly.’

As for me, I’m going to stick to my everyday lifestyle — a vegetarian who exercises a lot — rather than start popping pills.


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