Tuesday 13 October 2009

Homeopathy - estimating truth

This post was prompted a similar one by my cousin .. here..
Homeopathy is popular world wide, perhaps the most prominent of the alternative medicine systems. There is a Hospital in Glasgow, a stone's throw from my house.
Having said that, I am not about to throw stones at homeopathy.................
The fundamental healing 'principle' of homeopathy is 'similia similibus curentur' or, in english, 'like cures like'.
This isn't like, you know, teenagerese, dude.
Hahnemann, the founder of homeopathy, worked out that cinchona, taken on its own, induced a malaria like condition. He postulated that you could cure diseases by using medication that mimicked the symptoms of that disease. In other words, to treat hypertension, you would use a drug that increases your blood pressure, asthmatics would benefit from drugs that cause wheezing, and laxatives would cure diarrheas!
Now, this idea is not entirely crazy. For example, capsaicin, or chilli extract can be used to treat burning pain, and the antidote for morphine has very similar effects to it. However, these are specific instances, and generalising it is a bad idea. DONOT try to cure headache by listening to Black Sabbath. And, bungee jumping is not a cure for vertigo.
Another basic principle of homeopathy is the technique of 'super diluting' pharmacological agents to improve their efficacy.
In the mid eighties, a french immunologist, Jacques Benveniste sought to use research to provide scientific basis to homeopathy. he conducted a randomised controlled trial, (RCT) the gold standard for evaluating any treatment in medicine.
Amazingly, the study showed that indeed, diluting did enhance the effect of the drug.
Benveniste sought to publish this in 'Nature' - a highly respected scientific journal.
The editorial board of Nature were in a difficult position. They could not decline to publish the article. Over the years, 'Nature' has published ground breaking articles, some on which were not initially accepted by the scientific community. On the other hand, they had a lot of difficulty in accepting those results themselves. They did something very unusual. they published it with a sort of a disclaimer, and added conditions - i.e. Nature would get their experts to review the study process, and get a few more groups to reproduce the results.
(
Human basophil degranulation triggered by very dilute antiserum against IgE. E. Davenas, J. Benveniste et al.Nature.30 June 1988. 333; 816-818) .

The disclaimer read,

............Readers of this article may share the incredulity of the many referees who have commented on several versions of it during the past several months. The essence of the result is that an aqueous solution of an antibody retains its ability to evoke a biological response even when diluted to such an extent that there is a negligible chance of there being a single molecule in any sample. There is no physical basis for such an activity. With the kind collaboration of Professor Benveniste, Nature has therefore arranged for independent investigators to observe repetitions of the experiments. A report of this investigation will appear shortly......

Nature commissioned three experts to scrutinise the study as it was being conducted in Professor Benveniste's lab. This 'committee' included a magician, James Randi, well known for his sceptic views. To the relief of many scientists watching this around the world, the committee pointed out a few obvious problems with the study design. Mainly, with observer bias - which means, if your study requires an observation to be made, (counting the number of cells under a microscope for example), using an observer who has a reason to favour one side or the other of the result will consciously or subconsciously bias the observations.
In other words, if you appoint a Congress MP to record the political affiliation of a group of voters in your study of voting patterns, it is highly likely that Congress will emerge as the most popular party.
The actual graphs in the original article are very revealing. The response of the cells appear as a series of peaks, and these peaks are exaggerated as the dilution proceeds giving one the impression that the effect is enhanced.
Needless to say, the study has been discredited, in spite of Professor Benveniste's efforts to fight back, resorting to theories such as 'digital memory' to explain the apparent 'potent' effects of pure water. If you believe him, water molecules retain 'memory' of the substances they have been exposed to, and continue to have effects. The argument continue to date, with fairly vitriolic debates on either side. Here's one against the study. I don't think any one however, questions the integrity of Professor Benveniste. His study was defective, while his intentions were honurable.

If you have read my previous post, you probably know that I am a weak minded ditherer unable to decide one way or the other on any controversial issue.
Nothing's changed since then............I am still wishy washy.

I agree that homeopathy has no scientific basis. Does this mean we should never trust or practice homeopathy.?
On the surface, modern medicine appears to be built on solid science, facts, and well conducted experiments. However, any experienced practitioner will tell you the process of verifying truth in medicine is a fairly difficult one. Statistics never allows you to make a clear yes/ no statement, only likelihoods. (Lies, d....d lies and statistics, remember?).
In practical terms, everyday practice is a mixture of weak evidence, lots of experience, black magic and sometimes, pure chance.

Modern medicine should not hope to assume a position of superiority because it is more 'scientific' because our methods of estimating truth is still in its infancy. The only reason we can feel proud is the fact that it is always searching, improving and willing to accept its own weaknesses. Above all it is accountable.

And look at the above study. Nature was willing to publish it. The reason it received close scrutiny was that the results did not make sense, and the results were contrary to the traditional scientific thought. How many has Nature allowed through? How many have not received a closer scrutiny that they deserve? How many have remained 'truths' because no one has attempted to reproduce the results?

Unfortunately, the real world is where homeopathy as with any other medicine has unscrupulous elements who practice modern medicine by the backdoor, using dangerous drugs like steroids wily nily. In addition, homeopathic medicines use elements like mercury and can have disastrous consequences if used carelessly. When I mean homeopath I am assuming an honest practitioner.

On the other hand, sadly, the street cred of homeopathy has taken a blow ever since Prince Charles chose to throw his weight behind it.

To finish here's a homeopathy joke.

I remember 'Chakarvarthi' (name slightly changed), my dear friend from my clinical days. He was doing his BHMS (basic homeopathic degree in India), and I, my MBBS. We defended our systems loyally to each other. Chakarvarthi would end up saying - Look, Arnica, our most common used medicine, has no side effects! and I would retort, no wonder, it has no effects either.
Nearly 25 years later, I am not so sure. I guess neither is Chakravarthi.