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The link between cell phones and brain cancer Its now a definite ‘Maybe’


Following the release of the Interphone Study Group, report on cell phone safety, I suggested that a link between heavy cell phone use and brain cancer was missed because the authors analyzed their data using a flawed model of risk assessment.

At that time, the Interphone Study found that brain cancer (glioma) occurred 3.5 times more often in people who talked on their cell phone for at least one hour every day over 4 years (accumulating 1640 or more hours of talk-time). Moreover, the tumours mainly occurred in the brain’s temporal lobe, nearest the ear to which the cell phone was held.

Although other studies reported a similar association, the Interphone Study Group appeared to doubt this disturbing finding, suggesting that any increase in brain tumours was of dubious significance. Why? Because the excess in gliomas was seen only at the highest level of cell phone use, with no evidence of any effect at low or moderate exposure to radio frequency electromagnetic field (REF) emissions from cell phones.

Indeed, there appeared to be a 20% decrease in brain tumours in all but the most avid cell phone users — something the authors dismissed as biologically “implausible”.

Their conclusions were based on a rigid adherence to the standard “linear dose-response” model of risk assessment favored by toxicologists and health regulators: a chemical or physical agent (such as REF) must show a progressive linear (straight-line) rise in a harmful effect over a range of doses or exposures to be considered a danger to health.

Yet, there are hundreds upon hundreds of examples of substances, or physical agents, including ionizing radiation, whose dose responses are not linear, but “J-shaped” or “hormetic” (derived from hormone, meaning differing effects at low and high levels of exposure).

One notable example is alcohol: it is now widely accepted that low to moderate daily consumption of spirits increases longevity because of significant protection against cardiovascular disease, while higher consumption decreases longevity, in part by increasing cardiovascular deaths.

This and the all-too-many other exceptions to the linear rule led me to conclude that, “A ‘J-shaped’ dose-response (decreased risk of brain tumours with low to moderate use; increased risk with excessive use) is highly consistent with the findings of the Interphone Study Group.”

Is it possible that the comments in my blog influenced scientists at the World Health Organization’s International Agency for Research on Cancer (IARC)?

While thinking so would be highly presumptuous, let alone erroneous, I certainly welcome the agency’s May 31st announcement that it has now put “radiofrequency electromagnetic fields…associated with wireless phone use”, on its Category 2B list of “possible [not proven] carcinogens.

In reaching this decision, IARC scientists examined the findings of the Interphone study, among many others (both positive and negative), and decided it was “credible” that exposure to cell phone radiation could be a cause of brain cancer, although “chance, bias or confounding could not be ruled out with reasonable confidence.”

The IARC also correctly pointed out that some of the epidemiological studies it reviewed were carried out several years ago when cell phones emitted significantly higher levels of REF than those in use today.

What undoubtedly did influence their thinking was a recent U.S. National Institutes of Health (NIH) study showing that holding a cell phone to the ear for 50 minutes markedly increases brain activity in the area closest to the antenna. Could a daily “revving up” of brain cell metabolism lead to the development of a tumour years down the road? At this point, nobody knows.

Of even more potential concern, the study was carried out only in adults. What would be the long-term effect of cell phones on the brain tissue of children and pre-teens, whose thinner skull bones provide less protection from REF emissions?
The link between cell phones and brain cancer: It’s now a definite ‘maybe’

Responding to these concerns, Dr Nora Volkow, the lead NIH investigator, commented, “This study does not in any way indicate that [cell phones cause cancer]. What the study does is to show the human brain is sensitive to electromagnetic radiation from cell phone exposures.”

What does she, and the IARC recommend? More studies (of course).

In the meantime, they also suggest that cell phone users buy an earpiece to keep the phone away from the head, or send text messages rather than speak (thank goodness today’s youngsters would much rather text than talk!). As for those teens who literally “wear” their turned-on cell phones next to their skin (for example, under the bra), or sleep with their head next to them on the pillow every night, officials caution that they should stop.

Final word: I continue to believe that, like exposure to alcohol and ionizing radiation, a J-shaped hormetic dose-response applies to REF emissions from cell phones. Unlike heavy users, adults who use their cell phones in moderation probably need not worry about an increased risk of brain cancer; the hormetic dose-response model predicts that they even may be protected!

Trendy athletic therapy may not have any benefit


It’s called PRP, or platelet-rich plasma injection. There was a lot of press about it when a doctor in Toronto was charged for allegedly importing controlled or banned substances into Canada and the U.S. He had allegedly been using these substances for the treatment of some high-level athletes. Although these allegations haven’t been proven, and the athletes’ handlers deny any use of these substances, the issue of PRP was elevated to headline news.

PRP involves drawing blood from a patient, just as you would for a blood test, then spinning the blood in a centrifuge to separate out the cellular part of the blood from the plasma, or liquid part. This plasma is then reinjected into the patient at the site of their injury.

The idea is that chronic injuries fail to heal because there isn’t enough blood flow into those areas, to deliver the constituents in the plasma that are necessary to heal. By injecting the plasma directly into that area, one is supposed to improve healing.

But a study done in the Netherlands, published earlier this year in the Journal of the American Medical Association, showed that there is little benefit to the technique.

This study was a double-blinded, placebo-controlled study. This means that neither the researchers nor the patients knew if they were actually getting the PRP injection or an injection of salt water. 54 people with Achilles tendonitis were assessed, half got the PRP and half got the saline injection. All of them also had exercises prescribed. At the end of the six-month study, although both groups improved, there was no difference in the two groups in terms of their pain level or their activity level.

In other words, there was no significant effect of PRP in this study.


Other studies done on PRP have not been blinded. This biases patient to thinking that they’re going to get better. If you tell someone you’re doing something that will help, even if all you’re really doing is injecting saline, or giving a sugar pill, up to one-third of patients feel better. This is the placebo effect. By telling people you’re doing something helpful, some will feel better. If you charge people significant amounts of money for treatment, it means that already, even before doing treatment, those people who decide they’ll spend the money will more likely believe that the treatment helped. After all, they spent all that money, so the treatment must work, right?

While this technique has gotten a lot of press lately, there isn’t the body of scientific evidence behind it to make me comfortable recommending it or offering it to my patients.


Guideline Offers Guidance on Who Should Regularly Take ASA


ASA (acetylsalicylic acid, often sold as Aspirin) is often used by people to reduce their risk of stroke or heart disease. It works by being what is called an antiplatelet agent. Platelets are one of the components required to make blood clot. They are approximately one-quarter the size of red blood cells and are not whole cells.


ASA used as an anti-platelet agent has been a cornerstone therapy for patients who have blockages called atherosclerotic vascular disease in the coronary (or heart) vessels, cerebral (or brain) vessels, and peripheral beds, such as in our legs. This is known as secondary prevention.


For years, many people have used ASA as primary prevention to prevent the risk of a first heart attack or reduce the risk of a first stroke. To help better understand who should use ASA, the Canadian Cardiovascular Society created an anti-platelet guideline. Its goal is to provide a comprehensive, evidence-based, treatment centred statement on managing anti-platelet therapy in Canadian outpatients who have existing or are at risk of developing vascular disease.


It is important to remember that ASA can have a series of side effects, such as bleeding and heartburn. Other side effects include:

Bruising more easily
Nausea or Vomiting
Pain, Buzzing or Ringing in ears
Severe or continuing abdominal or stomach pain, cramping, or burning
Unusual tiredness or Weakness

What’s new in the guideline:

For men and women who do NOT have a vascular disease — your average healthy individual — ASA at any dose is not recommended for routine use to prevent what is called ischemic vascular events such as a heart attack or stroke. The guidelines do allow for some latitude and discretion for a prescribing doctor. In special circumstances, in men and women who don’t have evidence of present vascular disease but in whom the risk is considered high and a risk for bleeding is considered low, ASA 75 mg-162 mg can be considered for use, but the evidence to support this statement is not as strong as the statement against routine non-use.

Another group of people considered at high risk for cardiovascular disease are diabetics. The guidelines say that there is currently no evidence to recommend routine use of ASA at any dose for the primary prevention of vascular ischemic events in these patients. For patients with diabetes who are older than 40 and don’t have a high risk for bleeding, then ASA 75-162 mg daily can be considered for use for primary prevention if they have other cardiovascular risk factors. Those diabetics who have shown vascular disease can use low dose ASA for what would now be secondary prevention.

The guidelines as well have very specific recommendations for patients who have established disease and speaks to the use and combination of both ASA and other antiplatelet agents such as clopidogrel ( commonly known as Plavix). For example, patients who have already had a TIA (transient ischemic attack) or ischemic stroke should be treated with an antiplatelet agent. The choices can include ASA or other agents and the choice should take into account cost, ability to tolerate and other side effects.

The guidelines also point out that if you are on a low dose ASA, then use of anti-inflammatory medications should be undertaken with caution. It is recommended that only specific kinds of anti-inflammatory medication be used. The different kind of non-steroidal anti-inflammatory (NSAID) increase cardiovascular risk and if possible, should be avoided in patients who are considered at risk of ischemic vascular events. If you are wondering about your use of ASA, speak to your doctor.

The key points:

· For men and women without evidence of manifest vascular disease, the use of ASA at any dose is not recommended for routine use to prevent ischemic vascular events.

· There is currently no evidence to recommend routine use of ASA at any dose for the primary prevention of vascular ischemic events in patients with diabetes.

· Antiplatelet therapy should be continued for life in all patients with manifest ischemic vascular disease unless specifically contraindicated.

· Long term dosing of ASA > 162 mg/day should be avoided due increased bleeding risk and the lack of greater anti ischemic benefit over lower doses.

· Antiplatelet therapy should not be discontinued for minor or nuisance bleeding.