Risk of T2DM in RA

Inspired by Chen et al 2021.[1]

Tea fields, Alishan Township, Chiayi County, Taiwan. Photo by Alexa Soh on Unsplash.

T2DM – type 2 diabetes mellitus
RA – rheumatoid arthritis
CHD – coronary heart disease
aHR – adjusted hazard ratio
MA – manual acupuncture
EA – electroacupuncture
TNFα – tumour necrosis factor alpha (a potent inflammatory cytokine)
LHID – longitudinal health insurance database (Taiwan)
NHIRD – national health insurance research database (Taiwan)
CCI – Charlson comorbidity index (see Can acupuncture prevent neck surgery?)

key to acronyms

This is another of the large retrospective cohorts from Taiwan, which I have featured regularly on this blog: Retrospective cohorts.

The first of these papers I noticed was also in RA.[2] It looked at the risk reduction in CHD associated with acupuncture use in patients with RA: CHD incidence in RA and acupuncture. The best aHR was for MA plus EA (0.36) and this appeared better than for either statins (0.69) or TNFα inhibitors (0.48).

In this paper they used the LHID, which is a representative sample of 1 million patients from the NHIRD that are followed up for 10 years. The NHIRD contains around 23 million patient and represents the vast majority of the population of Taiwan.

5581 patients between 20 and 70 years of age with newly diagnosed RA between 1999 and 2008 were found in the LHID. 416 were excluded because they already had T2DM before RA was first diagnosed. 224 died or withdrew from the NHI program within 6 months of developing RA, so they were also excluded. Of the remaining, 2237 were acupuncture users and 2704 were not. An acupuncture user was identified if they had received at least 1 course of acupuncture for RA, and a course was 6 treatments delivered consecutively with 1 month.

Unsurprisingly, the two groups were significantly dissimilar so adjustments were made for age, sex, urbanisation level, monthly income and CCI.

I have mentioned the CCI before: Can acupuncture prevent neck surgery?

If you want to measure you own CCI click here.

aHR of 0.73 equates to a 27% observed reduction in T2DM associated with acupuncture use

The aHR came out at 0.73, which doesn’t seem as dramatic as the figures I quoted at the start of this piece, but tucked away at the end of the paper they have listed the results according to the number of courses of acupuncture (they use the term package rather than course). This is a bit like a dose response relationship, apart from the fact that it is an association only, so we cannot call it a response. Anyway those patients who received 5 or more courses of acupuncture within the 15 year period of study had an aHR of 0.48 ie less than half the risk of developing T2DM.

men over 50 have a >50% risk reduction

It is interesting to note that the risk reduction appears to be more prominent in men than women, and in particular men over 50 (aHR 0.45). I guess this is the population with the greatest risk associated with chronic inflammation.

It really encourages me to promote the idea of patients with RA performing their own EA twice a week for prophylaxis of acute inflammatory flares (see this blog for the protocol I teach: CHD incidence in RA and acupuncture). If the anti-inflammatory effect of this type of stimulation mediates the reduced risk of T2DM and CHD observed in these large cohorts, that is even stronger motivation to encourage this treatment.

We desperately need good prospective research in this area…

References

1          Chen W-J, Livneh H, Chen C-H, et al. Does Use of Acupuncture Reduce the Risk of Type 2 Diabetes Mellitus in Patients With Rheumatoid Arthritis? Evidence From a Universal Coverage Health Care System. Front Med 2021;8:752556. doi:10.3389/fmed.2021.752556

2          Wu M-Y, Huang M-C, Liao H-H, et al. Acupuncture decreased the risk of coronary heart disease in patients with rheumatoid arthritis in Taiwan: a Nationwide propensity score-matched study. BMC Complement Altern Med 2018;18:341. doi:10.1186/s12906-018-2384-5


Declaration of interests MC