In this post I put together a group of related ideas that I've written about on this forum in the past. In short, I think that:
- we should see the placebo effect as a friend;
- we should devise methods to increase the power of the placebo effect;
- we should measure symptoms continuously;
- we should assume that there are many types of PD;
- we should run trials on PwP as individuals, not as part of a cohort;
- we should be very careful not to needlessly do anything which diminishes peoples' expectations of the therapeutic value of their treatments.

Placebo

A placebo is something which is not expected to have any "real" impact on an illness. Nevertheless, when used in the right context, placebos can relieve both the perception and the objective measurement of the disease. The BBC reporting work done in Canada states that "when [a PwP] responds well to a placebo, it isn't the case that he's simply coping better with his symptoms, or somehow battling through them. Instead, the placebo is triggering the release of dopamine in his brain." [1]

Therebo

Why limit ourselves to placebos? There are many potential therapies which are likely to be both safe and offer the possibility of true therapeutic benefit. As an example, consider water. Dehydration is a common problem with PwP. Anything which addresses this problem goes beyond being a placebo.

To avoid confusion with standard placebos, let's introduce a new word: "therebo". A therebo is defined to mean something that may have therapeutic power or may be just a placebo (THERapy or placEBO). In the context of Parkinson's, coffee and curcumin are examples of therebos; levodopa is not a therebo, it is a therapy. A therebo doesn't have to be a drug, it's anything that can possibly affect the symptoms or progression of the disease. For instance, transcranial magnetic stimulation and the forced exercise of the arms are therebos. Even ideas can be therebos, even the concept of a therebo is a therebo. A therebo doesn't have to be static, it can be a process, e.g. the act of following this forum from day to day involves reading both good news and bad news items, and commenting on some of these, often following a study of the literature, creating a sense of empowerment.

As defined above, there are an infinite number of therebos for PD, most of these should be free or almost free. They are readily available. They could be in use in weeks. The main problem is to get the buy-in of the medical establishment.

Therebo distillation

1. A committee of PD experts is formed to recommend what therebos should be considered. This would be influenced by theoretical concerns, the results of test tube experimentation, animal trials and any human trial data that is available. As time goes by, new information will arrive (not least through the therebo distillation process itself) and this may lead to changes in the therebos.

2. People who join the scheme should:
- continuously monitor their symptoms;
- report their symptom measurements to the database;
- to start with take no therebos, so as to build a baseline of results against which to measure progress;
- once basedlined they can decide whether or not to take a therebo, whether or not to continue with a therebo, whether or not to change therebos. Any decisions are reported to the database.

3. The database stores symptom data and all the therebo choices made. Software would be written to show the effectiveness of the therebos.

The claim is made that:
- good results would enhance the placebo effect;
- people will migrate to therebos which have better results;
- therebos with true therapeutic effect will gradually rise to the top;
- therebos which in spite of the screening turn out to do harm, will fall off the bottom of the list and cease to be used;
- people will stick with therebos which are giving good results for them, even when their overall score is poor, providing patient-centric treatment.

Ethics of therebos

One of the issues that doctors have when prescribing placebos (for instance, suggesting antibiotics to treat a suspected viral infection or, more seriously, performing sham surgery as part of a clinical trial) is that there is a degree of deception. One of the nice things about therebos is that there is evidence to support the therapeutic value of the treatment. Although this evidence is not conclusive, a rational case can be made that taking a therebo is in the patient's interest. There is no advantage in deception; everything should be open.

However, without strong reasons, one must be careful not to rubbish people's therebos. Even true therapies will have a placebo component increasing their effectiveness. Lidstone et al. report [2]:
"The strength of belief of improvement can directly modulate dopamine release in patients with PD."
This benefit can be lost, and harm done to the PwP, by reporting negatively on the treatment. This is not say that negative reporting is always wrong. A balance needs to be struck taking into account all the circumstances.

I'll be grateful for your comments.

References

[1] "The medicine in our minds"
Olly Bootle, BBC, 17 Feb, 2014

[2] Arch Gen Psychiatry. 2010 Aug;67(8):857-65. doi: 10.1001/archgenpsychiatry.2010.88.
"Effects of expectation on placebo-induced dopamine release in Parkinson disease."
Lidstone SC1, Schulzer M, Dinelle K, Mak E, Sossi V, Ruth TJ, de la Fuente-Fernández R, Phillips AG, Stoessl AJ
http://www.ncbi.nlm.nih.gov/pubmed/20679593

John