The paradigm of placebo

Is placebo a dirty word? Is it unethical?

David Barrow

Rehab Guru Co-Founder

Is place­bo a dirty word?

Is place­bo unethical?

I have heard it described as both and I want to chal­lenge this a lit­tle further.

WHAT IS A PLACEBO EFFECT?

In 1955, Hen­ry Beech­ers pub­lished ​‘The pow­er­ful Place­bo’ in the Jour­nal of Amer­i­can Med­ical Asso­ci­a­tion and he out­lined the dif­fer­ence between place­bo and a ​‘dum­my’. He described a ​‘dum­my’ as the pre­scrip­tion of a medicine/​procedure/​therapy which is intend­ed to have no effect. He quotes the Oxford dictionary’s descrip­tion of place­bo quite lit­er­al­ly as a med­i­cine giv­en to please more than to benefit.

These may seem to be the same thing when per­ceived from a phys­i­cal per­spec­tive, but his arti­cle is enlight­en­ing when we delve fur­ther into the research sur­round­ing this phe­nom­e­non. A sug­ar lump that is giv­en with the inten­tion of pleas­ing rather than ben­e­fit may seem uneth­i­cal. But what if it’s as effec­tive as the a real drug or ther­a­py intend­ed for that purpose?

Raul de la Fuente-Fer­nan­dez et al pub­lished a paper in 2002 from The Uni­ver­si­ty of British Colum­bia (1). This was a Ran­domised con­trolled tri­al involv­ing patients with Parkinson’s dis­ease (PD). Half the patients were offered an injec­tion with an active ingre­di­ent and the oth­er half, a ​‘con­trol’ injec­tion of saline. This was repeat­ed twice, the first time the patients were not told which they received and as the sec­ond injec­tion was admin­is­tered the sub­jects were told which they were giv­en. Positron emis­sion tomog­ra­phy (PET) was used to study the brain dur­ing and after the injec­tions to mea­sure the amount of dopamine released by the brains.

Humanity’s need to explain all of the ther­a­pies down to a phys­i­cal source has for­got­ten that pain goes beyond the phys­i­cal realm of understanding.

Peo­ple with PD have an impaired abil­i­ty to pro­duce dopamine, so accord­ing to the Oxford dic­tio­nary def­i­n­i­tion of place­bo there should be no dopamine release with saline injec­tions. Intrigu­ing­ly, patients who received place­bo injec­tions exhib­it­ed sig­nif­i­cant dopamine releas­es. The authors con­clude that dopamine release ​“is linked to expec­ta­tion of a reward in this case, the antic­i­pa­tion of ther­a­peu­tic ben­e­fit.” In oth­er words, the expec­ta­tion of the reward is as pow­er­ful as the reward itself.

Could you imag­ine the poten­tial of cre­at­ing heal­ing with­out the need for nasty side effects? Which would be more ethical?

This brings into ques­tion whether it is uneth­i­cal to refuse a treat­ment when there is anec­do­tal ben­e­fit despite a lack of evi­dence (per­ceived non-ben­e­fit) There is well estab­lished evi­dence to show no cor­re­la­tion between tis­sue dam­age and pain or even bio­me­chan­ics and pain, so what do we think is actu­al­ly hap­pen­ing when we deliv­er rehab, exer­cise or a pro­ce­dure in line with cur­rent guide­lines? Are we naïve enough to reduce an expla­na­tion down to sim­ply a phys­i­cal rea­son­ing? Is there place­bo in every­thing we do?

This also opens a ques­tion of con­trol groups used with­in research. It has long been believed that the admin­is­tra­tion of a pro­ce­dure with no ben­e­fit can be com­pared to an active treat­ment to mea­sure effect. If the above men­tioned research shows that control/​placebo ther­a­py might actu­al­ly have a sim­i­lar heal­ing effect as the active treat­ment, we ought not to com­pare treat­ments to a control/​sham treat­ment and instead rely more of the anec­do­tal evidence.

the expec­ta­tion of the reward is as pow­er­ful as the reward itself

Per­haps this is also why the Cochrane reviews reveal such a lack of high qual­i­ty evi­dence with rehab and med­i­cine for heal­ing. The research does not always cap­ture the behav­iour seen clinically.

If we con­sid­er the his­to­ry of med­i­cine, rehab and sport, we may all remem­ber the fre­quent use and anec­do­tal suc­cess of ultra­sound machine, ankle strap­ping and the mag­ic sponge. Despite the ultra­sound machine not being turned on, the tape being inef­fec­tive after 10 min­utes and a sponge not seem­ing to do any­thing on a sci­en­tif­ic lev­el, they all had some suc­cess in help­ing peo­ple to over­come pain. Humanity’s need to explain all of the ther­a­pies down to a phys­i­cal source has for­got­ten that pain goes beyond the phys­i­cal realm of understanding.

With­in the sci­ence of chron­ic pain, the under­stand­ing of Cor­ti­col remap­ping shows us that the pain expe­ri­ence may reside with­in the brain and not with­in struc­tur­al deformity.

Giv­en this, I won­der whether place­bo treat­ment might have inter­est­ing effects on the brain that we saw with­in the British Colum­bia study for peo­ple with mus­cu­loskele­tal or chron­ic pain?

Sure­ly there is place­bo in every­thing we do?

Per­haps expand­ing on the British Colum­bia paper allows us an insight into the poten­tial we all have for heal­ing when we look beyond the phys­i­cal. Per­haps our suc­cess in cre­at­ing a heal­ing envi­ron­ment has a lot to do with the con­fi­dence, com­pas­sion and kind­ness we take into the exchanges we have with clients and patients. A research arti­cle from The Pain Clin­ic in 2000 revealed stereo­types held by med­ical pro­fes­sion­als towards patients expe­ri­enc­ing a painful med­ical procedure(2).

It revealed that the major­i­ty of med­ical pro­fes­sion­als per­ceived old­er and less attrac­tive patients to expe­ri­ence less pain than those who were younger and more attrac­tive. What sort of com­pas­sion and kind­ness might a med­ical or exer­cise pro­fes­sion­al dis­play towards patients that they per­ceive as old­er or less attrac­tive? If we con­sid­er the 2002British Colum­bia paper, which teach­es that the expec­ta­tion of the reward is equal­ly pow­er­ful as the reward itself, it may be worth invest­ing in the meta aspects of heal­ing rather than pure­ly the physical.

REFERENCES

1. Fuente-Ferna´ndez R.D.L, Phillips A.G, Zam­burli­ni M, Calne D.B„ Ruth T.J, Stoessl A.J. (2002). Dopamine release in human ven­tral stria­tum and expec­ta­tion of reward. Behav­iour­al Brain Research 136: 359⁄363

2. Thomas Had­jis­tavropou­los, Diane LaChapelle, Car­la Hale & Far­ley K. MacLeod (2000). Age- and appear­ance-relat­ed stereo­types about patients under­go­ing a painful med­ical pro­ce­dure. The Pain clin­ic: 12(1).

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David Barrow

David is a Physiotherapist who has been involved in Professional Sport, battlefield trauma, chronic pain and the NHS. He continues to work clinically alongside his development role in Rehab Guru. David is passionate about Health tech to transform outcomes for patient

David Barrow

Rehab Guru Co-Founder