Author: Pixelkicks

Acupuncture Controls Hypertension In Groundbreaking Trial

Researchers find acupuncture effective for the treatment of hypertension in middle-aged adults. In a groundbreaking eight week acupuncture trial, an international research team documents that acupuncture causes significant improvements in both brachial blood pressure and central aortic blood pressure in hypertensive middle-aged adults. [1] The scientific investigation was a collaboration between researchers from Larkin Community Hospital (Miami, Florida), Marymount University (Arlington, Virginia), Nosov Magnitogorsk State Technical University (Russia), and Moscow Financial and Law University (Russia).

The researchers note that prior investigations find acupuncture effective for the treatment of hypertension. [2,3] However, they add that this investigation is the first study to measure acupuncture’s effects on resting aortic hemodynamics and stiffness. The researchers note, “We found that 8 weeks of ACU [acupuncture] therapy resulted in beneficial reductions of aortic hemodynamics and arterial stiffness. Our results indicate that ACU improves resting aortic vascular function in hypertensive middle-aged individuals.” [4]
The researchers note that their finding of acupuncture’s effectiveness in improving pulse wave reflection (Alx) confirms findings by Satoh et al. in their investigation of the effects of acupuncture point GV20 (Baihui). The international team measured Alx “as the difference between the late and early systolic peak relative to aortic pulse pressure.” [6] The findings of both Alx studies confirm that acupuncture effectively downregulates Alx, indicating decreased aortic stiffness. This is medically significant given that a 10% increase in Alx increases pathological cardiovascular event risks by 31.8%. [7] As a result, the researchers suggest that acupuncture’s ability to downregulate Alx indicates that it reduces cardiovascular risks.

The study finds eight weeks of acupuncture effective in lowering aortic systolic blood pressure by approximately 10 mm Hg on average. Acupuncture lowered brachial systolic blood pressure by 10 mm Hg and 6 mm Hg for diastolic blood pressure on average. This is consistent with prior research. [8–10]

A strict protocolized acupuncture point prescription was used for all patients, with no variation for individual diagnostic considerations. The experimental design was randomized, controlled, and parallel. All needles were 0.20 mm in diameter and of 30 mm length. All needles were manually stimulated to elicit a deqi response and were subsequently retained for 20 minutes. The acupuncture points applied to all subjects (3 times per week for 8 weeks) were the following:
• ST36 (Zusanli)
• ST37 (Shangjuxu)
• PC5 (Jianshi)
• PC6 (Neiguan)
• LV3 (Taichong)
• SP4 (Gongsun)
• LI11 (Quchi)

The researchers upheld the finest ethical standards. The control group did not receive any intervention during the study or at any data points. Once the entire study was finalized, the control group was offered eight weeks of acupuncture therapy. In this way, the researchers were able to provide the same medical therapeutic options to the control group as was received by the acupuncture intervention group. This is a refreshing and important addition to the study design. The quest for knowledge was combined with humanitarian concerns.

The scientific data in this study is valid for a variety of reasons including randomization, strict controls, and a multiplicity of hemodynamic measurements including aortic blood pressure. This study is groundbreaking in that the measurements are not limited to brachial pressure readings taken by sphygmomanometric and oscillometric devices. While valuable, brachial pressures only measure the “peak and trough of the peripheral arterial pulse waveform.” [11] The international team agrees with Mayo Clinic (Scottsdale, Arizona) findings, that “aortic pressure is a better predictor of cardiovascular outcome than peripheral pressure.” [12] The pressure amplification effect also creates a discrepancy between aortic and brachial blood pressure readings, making aortic pressure a more accurate measurement. In addition, “antihypertensive medications have differing effects on central pressures despite similar reductions in brachial blood pressure.” [13]

The international team conducted their experiment using tonometry and waveform analysis, thereby making the blood pressure readings precise. This agrees with Mayo Clinic findings, “Applanation tonometry can overcome the limitations of peripheral pressure by determining the shape of the aortic waveform from the radial artery. Waveform analysis not only indicates central systolic and diastolic pressure but also determines the influence of pulse wave reflection on the central pressure waveform.” [14]

The research team cited prior investigations as to the possible mechanisms responsible for acupuncture’s antihypertensive therapeutic actions. Acupuncture exerts a homeostatic regulatory effect on “plasma nitric oxide (NO) levels, a potent vasodilator.” [15–16] Acupuncture also regulates plasma levels of potent vasoconstrictors (endothelin-1, angiotensin II). [17–18] Additional research was cited finding acupuncture effective in regulating sympathetic nervous system outflows, particularly when applied with electroacupuncture to acupoints PC5–PC6 and ST36–ST37. [19–21]

The findings indicate that acupuncture is an important treatment option for middle-aged patients with hypertension. Access to care becomes a concern given that there are a limited number of acupuncturists in many geographic regions. Many patients are underinsured, making cost a significant barrier to care. Finally, educating medical professionals on the importance of acupuncture as a treatment option for hypertension will help to improve appropriate referrals to licensed acupuncturists.

1. Terenteva, Nina, Oksana Chernykh, Marcos A. Sanchez-Gonzalez, and Alexei Wong. “Acupuncture therapy improves vascular hemodynamics and stiffness in middle-age hypertensive individuals.” Complementary Therapies in Clinical Practice (2017).
2. D.Z. Li, Y. Zhou, Y.N. Yang, Y.T. Ma, X.M. Li, J. Yu, Y. Zhao, H. Zhai, L. Lao, Acupuncture for essential hypertension: a meta-analysis of randomized sham-controlled clinical trials, Evidence-Based Complement. Altern. Med. 2014 (2014).
3. J. Wang, X. Xiong, W. Liu, Acupuncture for essential hypertension, Int. J. Cardiol. 169 (2013) 317e326.
4. Terenteva, Nina, Oksana Chernykh, Marcos A. Sanchez-Gonzalez, and Alexei Wong. “Acupuncture therapy improves vascular hemodynamics and stiffness in middle-age hypertensive individuals.” Complementary Therapies in Clinical Practice (2017), pg. 16.
5. H. Satoh, Acute effects of acupuncture treatment with baihui (GV20) on human arterial stiffness and wave reflection, J. Acupunct. Meridian Stud. 2 (2009) 130e134.
6. Terenteva, Nina, Oksana Chernykh, Marcos A. Sanchez-Gonzalez, and Alexei Wong. “Acupuncture therapy improves vascular hemodynamics and stiffness in middle-age hypertensive individuals.” Complementary Therapies in Clinical Practice (2017), pg. 17.
7. Ibid.
8. Y. Liu, J.-E. Park, K.-M. Shin, M. Lee, H.J. Jung, A.-R. Kim, S.-Y. Jung, H.R. Yoo, K.O. Sang, S.-M. Choi, Acupuncture lowers blood pressure in mild hyperten- sion patients: a randomized, controlled, assessor-blinded pilot trial, Com- plement. Ther. Med. 23 (2015) 658e665.
9. C. Yin, B. Seo, H.-J. Park, M. Cho, W. Jung, R. Choue, C. Kim, H.-K. Park, H. Lee, H. Koh, Acupuncture, a promising adjunctive therapy for essential hyper- tension: a double-blind, randomized, controlled trial, Neurol. Res. 29 (Suppl 1) (2007) S98eS103.
10. P. Li, S.C. Tjen-A-Looi, L. Cheng, D. Liu, J. Painovich, S. Vinjamury, J.C. Longhurst, Long-lasting reduction of blood pressure by electro- acupuncture in patients with hypertension: randomized controlled trial, Med. Acupunct. 27 (2015) 253e266.
11. Nelson, Matthew R., Jan Stepanek, Michael Cevette, Michael Covalciuc, R. Todd Hurst, and A. Jamil Tajik. “Noninvasive measurement of central vascular pressures with arterial tonometry: clinical revival of the pulse pressure waveform?.” In Mayo Clinic Proceedings, vol. 85, no. 5, pp. 460-472. Elsevier, 2010.
12. Ibid.
13. Ibid.
14. Ibid.
15. D.D. Kim, A.M. Pica, R.G. Dur an, W.N. Dura n, Acupuncture reduces experi- mental renovascular hypertension through mechanisms involving nitric oxide synthases, Microcirculation 13 (2006) 577e585.
16. H.S. Hwang, Y.S. Kim, Y.H. Ryu, J.E. Lee, Y.S. Lee, E.J. Yang, S.M. Choi, Electro- acupuncture delays hypertension development through enhancing NO/NOS activity in spontaneously hypertensive rats, Evidence-Based Complement. Altern. Med. 2011 (2011) 1e7.
17. Z. Huo, D. Li, J. Guo, S. Li, N. Ding, Z. Li, Effect of electroacupuncture stimulation on expression of angiotensinogen, angiotensin II type 1 receptor, endothelin-1, and endothelin a receptor mRNA in spontaneously hypertensive rat aorta, Chin. J. Integr. Med. 22 (2016) 778e782.
18. P. Pan, X. Zhang, H. Qian, W. Shi, J. Wang, Y. Bo, W. Li, Effects of electro- acupuncture on endothelium-derived endothelin-1 and endothelial nitric oxide synthase of rats with hypoxia-induced pulmonary hypertension, Exp. Biol. Med. (Maywood) 235 (2010) 642e648.
19. D.Y. Zhang, A.S. Anderson, The sympathetic nervous system and heart failure, Cardiol. Clin. 32 (2014) 33e45.
20. S. Uchida, F. Kagitani, H. Hotta, Neural mechanisms of reflex inhibition of heart rate elicited by acupuncture-like stimulation in anesthetized rats, Auton. Neurosci. Basic Clin. 157 (2008) 18e23.
21. S.C. Tjen-A-Looi, P. Li, J.C. Longhurst, Prolonged inhibition of rostral ventral lateral medullary premotor sympathetic neurons by electroacupuncture in cats, Auton. Neurosci. Basic Clin. 106 (2003) 119e131.

Pains and needles: brain scans point to hidden effects of acupuncture

Doctors in China have been pushing needles into patients’ skin, supposedly to restore the flow of healing “qi energy”, for more than 4,000 years. Sometimes it feels as though researchers in the west have been arguing about the practice for almost as long. After more than 3,000 clinical trials of acupuncture, many scientists are convinced that despite the benefits that patients might think they experience, the whole thing is simply a highly convincing placebo (pdf).

But are the sceptics missing something? A steady trickle of neuroscience studies suggests that relying on patients’ pain ratings in acupuncture trials might be hiding important changes in the brain.

Just as they do with drugs, scientists test whether acupuncture works against a placebo – a convincing but sham alternative. Methods vary but this often involves placing needles at non-acupuncture points, and using retractable needles that don’t penetrate the skin. The aim is to control for the effects of patients’ positive belief in a therapy: simply thinking that your pain is about to decline can trigger the brain to release natural pain-relieving molecules called endorphins (a type of opioid, chemically similar to painkillers such as morphine). The central assumption is that such effects occur equally whether patients get a placebo or an actual treatment.

The key test, then, is the difference between the two: if both groups report the same level of pain relief, scientists conclude that the treatment being tested doesn’t work. When acupuncture is subjected to trials like this, there is only a small effect above placebo, and often no difference at all.

Wei Shengchu, an acupuncture doctor demonstrates his craft by placing more than 1,000 needles in his head in front of a crowd in Nanning, southern China. Acupuncture treatments usually only require a small number of needles.

Neuroscientists have been studying how acupuncture affects the brain. It’s clear from many imaging studies that causing pain by inserting needles into the skin does influence brain activity, presumably by activating nerves close to the acupuncture point. Intriguingly, being pricked with needles seems to reduce activity in areas of the brain normally associated with pain, dubbed “the pain matrix”, says Hugh MacPherson, an acupuncture researcher at the University of York. “Rather than activating the pain matrix, it actually de-activates it.”

Sceptics argue that because of the lack of effect in clinical trials, such results are irrelevant. “It wouldn’t be at all surprising if being impaled with needles produced a signal in the brain,” says David Colquhoun, a pharmacologist at University College London and a prominent sceptic of alternative medicine. “It doesn’t tell you anything about how useful the needles are to patients.”

But a new generation of brain imaging studies is suggesting that perhaps researchers should refine their testing methods. There are now several trials showing that even when patients in acupuncture and placebo groups report similar drops in pain, the physical effects of treatment can be very different.

For example, Richard Harris, a neuroscientist at the University of Michigan, Ann Arbor, and colleagues used brain scans to investigate whether acupuncture triggers an endorphin hit in the same way that placebos do. They gave fibromyalgia patients – a condition characterised by chronic, widespread pain – either real or placebo acupuncture (using retractable needles at non-acupuncture points) then scanned their brains using positron emission tomography (PET) imaging. PET scans can’t see endorphins directly, but can detect the opioid receptors that these molecules target. Opioid receptors are present on the surface of nerve cells in the brain. When “locked” by endorphins (or other opioid molecules such as morphine), they prevent the cell from sending pain signals. In Harris’s experiment, a drop in the number of free, or unlocked, receptors in the patients’ brains would show that endorphins had been released.

After a single acupuncture session, as well as over a month-long course of treatment, both groups of patients reported a similar reduction in pain. In the placebo group, the PET scans did indeed show fewer free opioid receptors in areas of the brain associated with the regulation of pain, suggesting their pain relief was caused by endorphins. Harris assumed that in the real acupuncture group, he’d see something similar. “I expected that we would probably see the exact same thing between real and sham acupuncture, or that acupuncture might do it better,” he says. Instead, he saw the opposite. Within 45 minutes of the needling session, the number of free opioid receptors in the patients’ brains didn’t fall; it surged. “I was completely floored,” he says. Whatever the acupuncture was doing, it wasn’t working as a placebo.

It was the first hint, says Harris, that the central tenet of placebo-controlled trials – that placebo effects are always the same regardless of whether patients receive a real or fake treatment – might be wrong. “It has been assumed by the pain community that the placebo effect should be embedded in the active treatment group,” he says. “But it looks like actually placebos just do something completely different from the actual treatment … Both things are not necessarily operating together.”

Harris thinks that rather than representing a drop in endorphin levels, his results reveal an increase in the overall number of receptors. Other researchers have found that stimulating isolated neurons (nerve cells) directly causes extra opioid receptors to be expressed on the surface of those cells. Harris speculates that stimulating patients’ nerves with acupuncture needles might have a similar effect.

If he’s right, it’s tantalising evidence that while placebo acupuncture eases short-term symptoms by triggering pain-relieving endorphins, the real thing might actually help to reverse the underlying pathology of a disease. For example, fibromyalgia patients have fewer opioid receptors than healthy volunteers, leaving them less responsive to endorphins and overly sensitive to pain, but in Harris’s study, acupuncture “seemed to normalise the values back to healthy control levels,” he says. The larger that change, the more patients’ pain fell.

Harris is seeking funding to follow up on his results, including testing whether fibromyalgia patients who receive true acupuncture do better long-term.

More recently, research from Harvard Medical School has raised similar questions. A series of studies led by Vitaly Napadow, a neuroscientist at the Martinos Center for Biomedical Imaging at Massachusetts general hospital and Harvard Medical School, also concluded that patients’ initial pain ratings can hide important differences. He tested a therapy called electro-acupuncture, in which a mild electric current is passed through the needles.

Napadow focused on carpal tunnel syndrome, in which a squeezed nerve at the wrist causes numbness and pain. Unlike many chronic pain disorders, carpal tunnel syndrome is associated with physiological changes that can be measured objectively – nerve impulses at the wrist travel more slowly, for example.

In a randomised controlled trial published in March, 80 patients received either real electro-acupuncture or a fake version (in which retractable needles were placed at non-acupuncture points, with no electric current), in 16 sessions over eight weeks. Immediately after the treatment, all the patients reported similar reductions in their symptoms. Scientists would normally conclude from this result that the acupuncture didn’t work. But as in Harris’s trials, the underlying physiological effects were very different. The true acupuncture groups showed measurable improvements in the speed of nerve transmission and in the somatosensory cortex that weren’t seen in the placebo group. And only the true acupuncture groups still had reduced pain after three months. The larger the physiological changes measured by the team immediately after treatment, the better the patients felt three months later.

For MacPherson, the acupuncture advocate from the University of York, that’s a compelling result. “He’s showing changes in the brain in response to acupuncture that are clearly linked to the person’s improving clinical symptoms,” he says. MacPherson cautions that decisions regarding whether acupuncture should be prescribed to patients must always be based on clinical improvements in trials, not mechanistic studies, but he describes Harris and Napadow as “pioneers”, arguing that research like this is important for understanding how acupuncture might work, and suggesting how clinical trials could be better designed to pick up its effects.

These are single studies, however, and not everyone is convinced. “I think there is nothing that can’t be explained by bad statistical practice and cherry picking of evidence,” says Colquhoun. He describes Harris and Napadow’s research as the sort of thing that merits the hashtag neurobabble (or even neurobollocks). “Looking for explanations of a phenomenon before there’s any proven phenomenon to investigate is a waste of time,” he insists.

But Harris is unfazed, arguing that regardless of the sceptics, wider opinion is moving towards an acceptance of acupuncture. “Some people are not willing to change, despite the evidence,” he says. “But gradually, we are seeing a shift.”