Inspired by Jang et al 2020.
PD – Parkinson’s diseasekey to acronyms
fNIRS – functional near infrared spectroscopy
STRICTA – Standards for Reporting Interventions in Clinical Trials of Acupuncture
There is a lot of research published on acupuncture in PD, and I generally ignore it. So why did this paper catch my attention? Well the journal is published by SAGE and I did not recognise the title, so I check its IF (impact factor) and it is 4.17 – that’s a lot higher than most journals publishing acupuncture research.
I remember a paper on acupuncture in PD from nearly 20 years ago in a high impact journal (7.18) that reported improvements in sleep and patient reported outcomes, but not objective motor improvements. I have carried in my mind the idea that acupuncture can influence the sensory side of the nervous system, but not the motor side ever since.
This paper by Jang et al, and one prior paper by Lei et al, may have managed to change my opinion to a degree. They both use quite sophisticated analysis of movement to demonstrate the possible effects of acupuncture in PD. Jang et al used GAITRite to measure gait parameters. This is effectively a fancy long mat with lots of sensors in it that is plugged into a computer. Patients walk along the mat and the data is collected and analysed digitally. They also measured haemodynamic changes in the cerebral cortex using functional near infrared spectroscopy (fNIRS). This involves wearing a neoprene-like hood with lots of probes attached and wires coming out of them. I used to wear a neoprene hood for surfing when the sea temperature was below 10ºC to avoid what was called ‘ice cream head’. It felt more like your head was in a vice than the sensation of eating ice cream too fast, but I did not argue, I just bought a hood!
Jang et al randomised patients with PD to either acupuncture or a routine care control, and the acupuncture group received 2 sessions of acupuncture per week for 4 weeks. The only thing we are told about the acupuncture is that it was applied to the ‘dorsal side’ – that is the side that the central fin comes out on dolphins and orcas. That lack of information does not really bother me, since it rarely makes much difference in trials, but I was intrigued to see that the authors stated that they followed the STRICTA recommendations,[4,5] but then failed to report anything of note in the paper. The whole point of STRICTA was to improve the reporting of interventions in acupuncture trials.
The trial did not pick out any primary outcomes, and there were 12 measures reported for gait assessment before and after the intervention. Eight of these were generated by the fancy mat (GAITRite), and 4 of them showed highly (p<0.01) or very highly (p<0.001) significant differences between groups in favour of the acupuncture intervention. The reason for mentioning these p values is to note that some of them were so small as to negate the potential criticism of a lack of a correction for multiple statistical tests.
In particular acupuncture appeared to improve the hypometric gait of PD patients (high cadence, short steps), with an increase in stride, swing time and single [leg] support times. Furthermore, fNIRS outcomes demonstrate significant increases in oxyhaemoglobin levels in the prefrontal cortex of acupuncture treated PD patients when walking on a treadmill.
Whilst this is quite convincing data, and most of the outcome measures can be considered objective, I cannot help remembering the rather dramatic responses to placebo in PD patients, and the fact that this trial was not sham controlled.
Benedetti and colleagues comment that the psychosocial context, for example a therapeutic ritual, can change both the chemistry and circuitry of the patient’s brain. However, in a more recent paper on bradykinesia in PD patients they found that significant placebo effects could only be generated following conditioning with an active substance, and placebo injection alone had no particular effect.
Repeated sessions of acupuncture, of course, could condition placebo responses, but this last paper suggests that there must be some real effect in the first place.
1 Jang J, Park S, An J, et al. Gait Disturbance Improvement and Cerebral Cortex Rearrangement by Acupuncture in Parkinson’s Disease: A Pilot Assessor-Blinded, Randomized, Controlled, Parallel-Group Trial. Neurorehabil Neural Repair Published Online First: 16 November 2020. doi:10.1177/1545968320969942
2 Shulman LM, Wen X, Weiner WJ, et al. Acupuncture therapy for the symptoms of Parkinson’s disease. Mov Disord 2002;17:799–802. doi:10.1002/mds.10134
3 Lei H, Toosizadeh N, Schwenk M, et al. A Pilot Clinical Trial to Objectively Assess the Efficacy of Electroacupuncture on Gait in Patients with Parkinson’s Disease Using Body Worn Sensors. PLoS One 2016;11:e0155613. doi:10.1371/journal.pone.0155613
4 MacPherson H, Altman DG, Hammerschlag R, et al. Revised STandards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA): Extending the CONSORT Statement. J Evid Based Med 2010;3:140–55. doi:10.1111/j.1756-5391.2010.01086.x
5 MacPherson H, White A, Cummings M, et al. Standards for Reporting Interventions in Controlled Trials of Acupuncture: The Stricta Recommendations. Acupunct Med 2002;20:22–5. doi:10.1136/aim.20.1.22
6 Benedetti F, Carlino E, Pollo A. How Placebos Change the Patient’s Brain. Neuropsychopharmacology 2011;36:339–54. doi:10.1038/npp.2010.81
7 Frisaldi E, Carlino E, Zibetti M, et al. The placebo effect on bradykinesia in Parkinson’s disease with and without prior drug conditioning. Mov Disord 2017;32:1474–8. doi:10.1002/mds.27142