Friday, July 22, 2011

WHO plan to classify TCM is worrying

Jul 21, 2011

By Andy Ho

THE medical fraternity has maintained a deafening silence over news of the commercial use of leeches for blood letting.

Perhaps it is politically incorrect to criticise any traditional therapy, now that it may have the imprimatur of the World Health Organisation (WHO).

From last year, the WHO has been putting together an International Classification of Traditional Medicine (ICTM) in an attempt to standardise, basically, traditional Chinese medicine (TCM) terminology.

Slated for completion in 2014, this project came on the heels of its own publication in 2007 of the WHO International Standard Terminologies on Traditional Medicine in the Western Pacific Region.

What is worrying is the agency's plan to incorporate the ICTM into the International Classification of Diseases (ICD), which scientists use to study medical therapies.

The WHO argues that a dearth of standardised data causes TCM to fall on 'the dark side of health care'. By harmonising data-gathering, the ICTM will bring TCM 'into the light of science', it hopes.

But can it? Note that the efficacy of TCM therapies is not pursued in the ICTM. The project solely involves the science of classifying diseases, or nosology.

Unfortunately, TCM's pre-scientific nosology is incommensurable with science. Consider three examples in the 2007 work. Diagnosis 3.1.140 is 'running piglet', characterised by 'a feeling of masses of gas ascending within the abdomen'. Diagnosis 2.10.30 is 'syndrome of liver fire blazing the ear' with 'painful distension in the ear... dizziness, bitter taste... reddened face... irascibility, reddened tongue with yellow coating'. And diagnosis 2.9.28 is 'wind-cold fettering the lung' due to 'attack of wind-cold, which impairs normal flow of lung qi'.

This way of classifying diseases is not based on any verifiable bases in physiology and biochemistry. Instead, it resorts to ideas of association, usually based on symptoms or assumed underlying causes.

Undeniably, most cultures in times past have done so. Up to the 18th century, Western cultures classified people according to their complexion, which was thought to reflect one's mix of 'humours'. People were choleric (if predominantly influenced by yellow bile), melancholic (by black bile), phlegmatic (by phlegm), or sanguine (by blood).

So diseases were understood according to this humoral theory. Thus, 'melancholia' or sadness was supposedly caused by an 'excess of black bile', an imaginary humour said to be secreted by the spleen.

But since science is truth and not a Western construct per se, pre-science Western nosology demonstrated the same lack of logic as TCM still does. Today, however, all diagnostic labels in 'Western' or science-based medicine refer to discrete diseases arising from a specific causative agent or causal mechanism.

Not so in TCM. Instead, as the 2007 WHO book admits: 'The philosophical background of this suite of standard (TCM) terminology is Taoism.' And this is how Taoist ideas work out in Neijing Suwen, the Chinese medical classic: TCM's organising idea has the human body working through zang-fu organs.

But these are less anatomical entities and more functional concepts. The zang organs (heart, liver, spleen, lung, kidney) are solid and 'yin', or feminine.

The fu organs (small intestine, large intestine, gall bladder, urinary bladder, stomach and sanjiao) are hollow and 'yang', or masculine. (Sanjiao are the trunk's lower, middle and upper cavities.)

Each zang has a specific fu counterpart and each zang-fu pair is assigned to one of the five elements (wood, fire, earth, metal and water). The TCM diagnostician must attend to all these parameters.

Moreover, the zang-fu pairs are connected to 12 standard channels for qi, or the life force, to flow around. When the flow is good and the zang-fu pairs - thus yin and yang - are in equipoise, one is healthy. In the opposite case, one falls ill. Rechannelling qi to the 'correct' zang-fu pairs using, say, acupuncture or herbs should restore health.

Note zang-fu are not primarily anatomical entities. They refer more to bodily functions as conceived metaphysically in Taoist thought. If you find this hard to wrap your head around, that is the point.

TCM's central organising concept is incomprehensible apart from metaphysics. But bodily functions conceived metaphysically cannot be mapped onto physical bodily processes that are now understood at the molecular level in science.

A metaphysical category, zang-fu, which is TCM's centrepiece, cannot be verified or disproved experimentally. Proponents say comparing Chinese and 'Western' medicine is like comparing apples and oranges, so science is not applicable to TCM.

Yet, as the 2007 WHO work asserts, 'both... aim at maintaining health and treating diseases, so there must be some overlap between the two systems'. In fact, TCM claims to be a parallel system for understanding and treating disease. If so, it either maps onto reality or not.

The periodic table is a taxonomy of all the elements (based on their number of protons). If you threw into it some alchemistry concepts, the table would no longer mirror reality. Such a bicultural table can make no sense of, say, radioactivity.

Likewise, a nosology not based on bioscientific facts cannot reflect the reality of bodily disease processes. Thus, assigning ICD codes to TCM categories serves only to legitimise an erroneous nosology.

Doctors should lead in rejecting the WHO's politically correct salad bowl of science and pre-science categories.

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