3.1.3 Trial Acupuncture Protocols
The studies tested the effects a variety of different types of acupuncture on hypertension. Two-thirds of the trials (n=4, 66.7%) tested traditional Chinese acupuncture, though Kim et al. (2012) tested traditional Korean acupuncture and Yin et al. (2007) tested modern Korean acupuncture. The studies involved accessing a variety of acupoints – from a single acupoint (Zheng et al., 2016: acupoint LR3) to up to thirty-two acupoints (Macklin et al., 2006: acupoints not specified). In half of the trials (n=3, 50.0%) of the trials, individualised acupoints were selected for a patient after a diagnosis considering their unique physiology, underlying diagnoses and/or current physical wellbeing (Macklin et al., 2006; Flachskampf et al., 2007; Yin Zheng et al., 2018).
The trials used a variety of different acupuncture protocols. The intervention period, throughout which patients received acupuncture, ranged from 2 weeks (Zheng et al., 2016) to 8 weeks (Macklin et al., 2006; Yin et al., 2007; Kim et al., 2012). In the intervention period, patients received between 10 acupuncture sessions (Zheng et al., 2016: 5 sessions per week) and 22 acupuncture sessions (Flachskampf et al., 2007: 3 to 4 sessions per week). In most of the trials (n=5, 83.3%), the acupuncture sessions were 30 minutes’ duration (Macklin et al., 2006; Flachskampf et al., 2007; Yin et al., 2007; Zheng et al., 2016; Zheng et al., 2018), though in Kim et al.’s (2012) trial the acupuncture sessions were limited to 20 minutes’ duration. The participants were followed-up for an average of 19.3 weeks, ranging from 8 weeks (Yin et al., 2007; Kim et al., 2012: no follow-up beyond trial period) and 12 months (Zheng et al., 2016).
3.2 Findings – Effects of Acupuncture on Hypertension
Overall, there was a lack of consensus among the studies about whether acupuncture, in comparison to sham acupuncture, is effective at reducing systolic and/or diastolic blood pressure. Some of the trials selected for inclusion suggested acupuncture is more effective than sham acupuncture. Others suggested it might be more effective, and another found that it was not more effective. These findings are outlined in greater detail in the following section:
3.2.1 Acupuncture IS Effective at Reducing Hypertension
Half of the studies (n=3, 50.0%) concluded that active acupuncture is more effective than sham acupuncture for reducing blood pressure in people with hypertension. For example: in the trial conducted by Flachskampf et al. (2007), there was a mean reduction in participants’ blood pressure of 6.4mmHg (systolic) and 3.7mmHg (diastolic), while there was no reduction in the sham acupuncture group (p<0.001). In Yin et al.’s (2007) trial, the mean blood pressure for the group receiving acupuncture decreased from 136.8/83.7mmHg to 122.1/76.8mmHg, while again there was no change in the mean blood pressure for the control group (p<0.01). Similarly, in Zheng et al.’s (2018) trial, acupuncture resulted in an average decrease in participants’ overall blood pressure of 3.3mmHg, which was significant in comparison to the control group.
3.2.2 Acupuncture MAY BE Effective at Reducing Hypertension
One third of the studies (n=2, 33.3%) concluded that active acupuncture may be more effective than sham acupuncture for reducing blood pressure in people with hypertension. For example: the trial conducted by Kim et al. (2012) found that there were no significant changes in the blood pressure of patients receiving acupuncture except in relation to nighttime diastolic blood pressure, where there was a decrease of 2.5mmHg (p=0.041). Similarly, in Zheng et al.’s (2016) trial, the only significant change in the blood pressure of patients receiving acupuncture was in relation to systolic blood pressure, where there was a decrease of 5.2mmHg (p=0.006).
3.2.3 Acupuncture IS NOT Effective at Reducing Hypertension
The final study (n=