EA in FD 2022

Inspired by Wu et al, Yang et al, & Li et al 2022.[1–3]

EA – electroacupuncture
FD – functional dyspepsia or functional diarrhoea
FDys – functional dyspepsia (in this blog)
FDr – functional diarrhoea (in this blog)
IBS – irritable bowel syndrome
tid – ter in die (3 times a day)
tds – ter die sumendus (to be eaten 3 times a day)
MA – manual acupuncture
HADS – Hospital Anxiety and Depression Scale 

key to acronyms

These 3 papers are all from the journal eCAM. It is an open access journal using an author pays model, that is there is a fee to pay when you submit your paper as an author. The ‘article processing charge’ (APC) for eCAM is $2550, and in 2021 eCAM published a total of 1635 papers. That makes an estimated total revenue from APCs of over $4 million.

…an estimated total revenue of over $4 million

When you have the potential to make that much money per year and there is no paper version of the journal to print, there is a clear financial incentive to publish. Because of this we must be more careful as consumers of the information.

These 3 papers hang together quite well, and there are no outrageous claims, but I will reframe some of the findings for you. All three papers are on functional disorders of the bowel, and 2 out of the 3 use EA.

The first paper caught my eye because the title teases the practitioner reader into thinking they are going to get a steer on the optimal intensity of EA to use when treating FDr. Unfortunately, this 3-arm trial did not show any differences between interventions in the primary outcome, and it was not powered for either equivalence or non-inferiority; nor did it achieve its own calculated power, which appears to have been based on a pharmaceutical trial in IBS. Now do you get a sense of the lure of the 4 mil?

Two of the three arms received EA applied to ST25 and BL25 bilaterally, and the third arm received the drug loperamide 2mg tid for 4 weeks.[4] The EA was applied 5 times a week for 2 weeks then 3 times a week for 2 weeks, so that is a total of 16 sessions in 4 weeks. Each session was 30 minutes at 2/50Hz and either 0.1 to 0.8mA (low intensity) or 1.0 to 1.8mA (high[er] intensity). They used what was referred to as an auxiliary needle, placed 2mm away from each point, and inserted 2mm, to create a pair of needles at each point. The main points were needled with 0.30x50mm needles and the auxiliary points with 0.18x13mm needles. I have seen this before, and whilst it allows separate control of intensity at each site, which is good, the superficial placement of the shorter finer auxiliary needle means that the main electrical stimulation may occur in the skin where there are lots of large, electrically sensitive nerves fibres. This is not so good, so personally, whilst I often use pairs of needles close together, I always place both needles into the target tissue, usually muscle.

The primary outcome was the proportion of patients with normal defaecation based on stool frequency and consistency. There was no difference between groups and all groups improved significantly with a trend in favour of the low intensity EA group.

The last of the secondary outcomes were Zung’s self-rating scales for anxiety and depression,[5,6] and both of these showed the most improvement in the low intensity EA group, with a significant between group difference when compared with the loperamide group.

I guess this trial gives us clinicians a hint to go easy on the EA stimulation to the trunk in FDr.

Staying on the subject of anxiety and depression in FD, the second paper is a subgroup analysis of a large study I highlighted on the blog in May 2020: Functional dyspepsia 2020. The original study was a large (n=278) sham-controlled trial of MA in post prandial distress syndrome (the largest subcategory of FDys). This subgroup analysis just looked at those patients who received real MA (n=138) and divided them into groups based on anxiety and depression. They used a different scale to measure anxiety and depression (HADS).[7]

The treatment in this trial was 12 sessions over 4 weeks and follow-up continued for a further 3 months. In terms of response rates, the non-anxious and non-depressed patients did significantly better at 1 month follow-up, but by 3 months there was no difference between the subgroups. The primary outcomes of the original trial were at the end of treatment (4 weeks). At this time point there was no difference between either subgroup in response rate, but the anxiety group was worse in terms of elimination rate (essentially the symptomatic cure rate). Having said that, this subgroup caught up over the 3 months follow-up and by week 16 the elimination rate was just under 30% in both subgroups.

I’m not sure what we can learn from this apart from reassuring our anxious and depressed patient with FD that they will eventually respond as well as their non-anxious or non-depressed peers.

The final paper is a laboratory study on a rat model of FDys created with daily gavage of 0.1% iodoacetamide for 6 days at the start of the experiment. Yes, that is gavage and not lavage – I had to look it up recently for a paper in our journal. Gavage is effectively lavage of the stomach.

Eight weeks after the model was initiated EA was applied daily for 10 days to a single pair of acupuncture points on the abdomen or lower limb. Points used were ST36 (cheering), ST37, ST39, ST25, CV4, CV12. The latter two were paired with a second needle very close by. EA was applied at 100Hz and 1.0mA for 30 minutes. I would have gone for a mixed low and intermediate frequency.

The outcomes were a measure of gastric emptying and a series of markers in the duodenum assessed by immunofluorescence and Western blot analysis.

…in particular ST36 of course

The leg points came out best on most measures, in particular ST36 of course. EA to these points tended to reduce inflammation and restore tight junctions in the duodenum. I would not have expected to see much difference between three points in tibialis anterior, but there were one or two surprises.

I’ll give you all the in-depth results on Wednesday.

References

1          Xu X, Zhang M, Wu X, et al. The Effect of Electroacupuncture Treatment with Different Intensities for Functional Diarrhea: A Randomized Controlled Trial. Evid-Based Complement Altern Med ECAM 2022;2022:2564979. doi:10.1155/2022/2564979

2          Yang N-N, Yang J-W, Tan C-X, et al. The Influence of Psychological Status on Acupuncture for Postprandial Distress Syndrome: A Subgroup Analysis of a Multicenter, Randomized Controlled Trial. Evid-Based Complement Altern Med ECAM 2022;2022:1614648. doi:10.1155/2022/1614648

3          Li Y-J, Yang N-N, Huang J, et al. Effects of Electroacupuncture at Different Acupoints on Functional Dyspepsia Rats. Evid-Based Complement Altern Med ECAM 2022;2022:6548623. doi:10.1155/2022/6548623

4          Ellis C. Ter die sumendus. BMJ 2006;332:1378–1378.

5          Zung WW. A rating instrument for anxiety disorders. Psychosomatics 1971;12:371–9. doi:10.1016/S0033-3182(71)71479-0

6          Zung WW. A self-rating depression scale. Arch Gen Psychiatry 1965;12:63–70. doi:10.1001/archpsyc.1965.01720310065008

7          Zigmond AS, Snaith RP. The hospital anxiety and depression scale. Acta Psychiatr Scand 1983;67:361–70. doi:10.1111/j.1600-0447.1983.tb09716.x