Prof Wendy Burn, president of the Royal College of Psychiatrists (Image: publicity picture)
Burn fuelled the fire earlier this year when she, along with RCP colleague, David Baldwin, wrote a letter to the Times newspaper claiming, "We know that in the vast majority of patients, any unpleasant symptoms experienced on discontinuing antidepressants have resolved within two weeks of stopping treatment." (back story)
Burn's presence and engagement on Twitter is refreshing, and sometimes very frustrating. For the advocates who criticise psychiatry and the wanton use of antidepressants, it's been eye-opening and, at times, jaw-dropping. None more so than the following snapshot of tweets she and I had.
Here's the order in which they were asked and answered.
It would appear Burn bases her diagnosing and prescribing system based on faith rather than actual science. Here's why:
First off, by Burn's own admission, she works, in the main, with elderly patients, 65 and older.
Burn asserts that elderly people metabolise more slowly so drugs stay in their system longer, which, assumes Burn, minimises withdrawal.
Drug metabolism is the process by which the body breaks down and converts medication into active chemical substances. The primary site of drug metabolism is the liver, the organ that plays a major role in metabolism, digestion, detoxification, and elimination of substances from the body.
Research has found that people fall into one of four general metabolizer types. (1)
The Four Metabolizer Types
- Poor metabolizer: Patients who are poor metabolizers experience a very slow breakdown of medications, making side effects more pronounced. That means standard doses of certain medications may not work as intended.
- Intermediate metabolizer: A slowed metabolism may impact breakdown of medications, causing effects similar to poor metabolizers, but not as pronounced.
- Extensive metabolizer: Considered a “normal” rate of metabolism. Patients are likely to metabolize medication normally and medication is likely to work as intended.
- Ultrarapid metabolizer: Patients in this group metabolize medications too quickly to experience relief from symptoms of depression or other disorders.
Are elderly people more prone to a poor metabolizing system?
According to statistics (2), 40% of the elderly regularly take five or more concomitant prescription medications, add to this the fact that many medications have more than one metabolic pathway, and you can see how prescribing, or adding medication into the mix, can be extremely dangerous for anyone 65 and older.. Furthermore, if, as Burn assumes, 'most (elderly) are slow metabolizers', then without any test in place prior to prescribing she, along with other treating physicians are basically taking it on faith that the person in front of them is a poor, intermediate, extensive or ultrarapid metabolizer.
I asked Burn if she carried out any Pharmacogenomic testing prior to prescribing to her elderly patients. She never responded.
If you, like me, struggle to grasp how the metabolizing system works then a layperson's explanation may help.
Let's say I am a poor metabolizer and my best friend is an extensive metabolizer. Both of us are depressed and both have been prescribed an antidepressant of the SSRI family.
After taking the drug at exactly the same time, my friend excretes it far quicker from his body so when it's time for our next dose I am at a slight disadvantage because my second dose will be topping up my first dose, whereas my friend will have most of his original dose excreted from his system or a higher percentage of it than I.
Now, let's say we are both on these drugs for 6 weeks. The build-up of the drug in my body will be far greater than that of my friend. He may be able to withdraw without any problems, whereas I may find it extremely difficult to withdraw. I may also have toxicity in my system.
If Burn assumes that the elderly are slow metabolizers then when prescribing to them she is doing so by using a belief rather than any scientific testing such as pharmacogenomic testing. If, by her own admittance, she knows they are slow metabolizers then they will more than likely endure what I did in the example above.
One should also take into account a person's genetic factors when prescribing. Genetic factors account for 20 to 95% of patient variability in response to individual drugs. (3) - It seems perfectly logical then that a prescriber would choose to ensure the safety of their patient when prescribing a drug. By claiming that they 'monitor' patients is clearly not good enough, particularly when they have a tool at their disposal that can predict if their patient will struggle on the drug they prescribe, moreover, if the drug will stay in their system longer making the withdrawal process more difficult.
Quite why this isn't mandatory will, more than likely, be blamed on the expense and how 'time-consuming' the whole process can take. I really don't buy into the 'monitoring' angle, I mean, how can a prescriber monitor a patient 24/7?
Burn is on a hiding-to-nothing when she is posed questions by many drug safety advocates on Twitter. I give her kudos for attempting to tackle the hundreds of tweets she receives daily now that she has unblocked many of those who previously opposed her views.
Science can only be the winner here and not assumptions. One prescriber may have different approaches than another - one may be more thorough when deciding to prescribe. Assuming a patient may or may not be a slow metabolizer is tricky ground though. If we can't predict (without pharmacogenomic testing) then should psychiatrists and doctors really be prescribing toxic drugs to patients at all? It's Russian Roulette, but we are told, and always have been, that the benefits outweigh the risks.
Serotonin toxicity, often incorrectly called a "syndrome", is best managed by reducing and/or discontinuing the offending drug(s). If left untreated it can lead to akathisia, an emotional state that can sometimes include the emergence of strange and unusual impulses, often of an aggressive nature. It can also lead to violence and suicide. (4)
Burn, in defence of her statement to criticisms of her Times letter, has claimed that in her clinical experience she has never seen a patient suffering from severe withdrawal from antidepressants. We have to take this at face-value as there is no way of knowing if, a; Burn knows the difference between antidepressant withdrawal and "depressive symptoms" and, b; whether or not she is being truthful.
Many elderly patients trust prescribing physicians, my own mother did when she was alive. Many don't like to 'rock the boat'. We often hear the elderly make claims such as, "The good old doctor went through years of med school, so they know exactly what they are doing", and, "they wouldn't give me a drug that could harm me."
Reminds me of the statement King & Spalding's lead attorney made in his closing statements to the jury in the Dolin v GSK Paxil-induced suicide trial:
“Don’t you think if these medicines caused suicide someone would have spoken up?” ~ Andy Bayman - King & Spalding.
The jury did.
I long for the day when Wendy Burn and her peers acknowledge that the drugs they prescribe to children, adults and the elderly may be the cause of depressive symptoms and feelings of hostility. Judging by her current stance, however, I think we may be in for a long wait.
Bob Fiddaman
(1) Fast, Slow or In-Between: How Your Genes Affect Medication Success
(2) Pharmacogenomic Treatment Support, Today’s Geriatric Medicine, Vol. 7 No. 4 P. 20
(3) Hypothesis: comparisons of inter- and intra-individual variations can substitute for twin studies in drug research.Pharmacogenetics. 1998 Aug;8(4):283-9.
(4) What is akathisia?
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