Laser acupuncture protocol for essential systemic arterial hypertension: randomized clinical trial 1

ABSTRACT Objectives: to evaluate the efficacy of a laser acupuncture protocol developed and applied by nurses in arterial hypertension patients. Method: randomized, multicenter, triple-blind and two-armed clinical trial. The sample consisted of 102 participants, 51 per arm, both sexes, aged between 30 and 75 years, undergoing drug therapy for a year or more, with difficulty to control blood pressure, maintaining regular measures >140x90 mmHg. Participants underwent six standard or simulated laser-acupuncture sessions, for 24 minutes, within a period of six weeks. Descriptive analyzes expressed as frequencies of occurrences, means and medians were used, and analysis of the association between variables was performed using Student’s t-test and Anova, using Statistica® software, version 12.0. The significance level was set at 5% (alpha=0.05). The comparison between blood pressure measurements was performed using Student’s t-test for paired samples and Anova for repeated measures. Results: a significant reduction in systolic (p<0.001) and diastolic (p<0.001) blood pressure was observed among participants in the intervention arm, which was not observed in the simulation arm. Conclusion: the results have demonstrated the efficacy of the protocol. Reduction and control of blood pressure have been demonstrated, indicating the possibility of using this technology for the care of patientes with essential systemic arterial hypertension. Brazilian Registry of Clinical Trials. UTN: U1111-1177-1811. Clinical Trials NCT02530853.


Introduction
Essential Systemic Arterial Hypertension (SAH) is an important risk factor, precursor and potential factor for the progression of Cardiovascular Diseases (CVD) and their complications (1)(2)(3) . A multifactorial condition characterized by a sustained increase in arterial blood pressure levels ≥140 and/or 90 mmHg (2) .
Blood Pressure (BP) control at levels below 140 mmHg for Systolic Blood Pressure (SBP) and 90 mmHg for Diastolic Blood Pressure (DBP) in patients with stages 1 and 2 hypertension, with low and moderate Cardiovascular (CV) risk, as well as those with stage 3 hypertension, has been strongly recommended as a therapeutic goal (2) . For those with stages 1 and 2, however, with a high CV risk, the recommendation differs, and the maintenance of blood pressure levels below 130x80 mmHg is indicated (2) .
The attainment of such results is influenced by several factors such as adherence to medication treatment, availability of the medication in the public health system, health professional/patient relationship, besides those related to the occurrence of adverse or undesirable events, intake of beverages and foods not recommended, smoking and sedentary lifestyle (1)(2)(3) .
The treatment has a multidisciplinary nature and is based on drug and non-drug strategies, and the latter are managed and supported by nurses, especially in the area of basic health care (1)(2)(3) . Several authors have pointed out AP as a complementary therapy in the control of SAH. The results indicate the possibility of its use for an effective control of blood pressure levels, which can be associated to different modalities of drug therapy and performed in several health care settings (6)(7) .
AP is a therapeutic modality of TCM that, through the stimulation of specific points in the body, called acupoints, promotes organic self-regulation to fight several health conditions/diseases (8) .
In SAH, this mechanism of self-regulation is related to the balance of the activity of the renin-angiotensinaldosterone system, in addition to involving plasma alterations of catecholamines and neurotransmitters, such as noradrenaline, serotonin and endorphin (9) . This technique can be applied through a noninvasive method, without the use of needles (laseracupuncture), through a minimally invasive method, with the use of extremely thin needles (traditional acupuncture), or through the association of needle use with electrical stimulation (electroacupuncture ), with these two modalities most often found in clinical studies for the demonstration of its safety and efficacy (5)(6) .
Laser-Acupuncture (LA) method also shows good safety and efficacy, however, studies on this modality are still incipient, as well as those involving the use of this technology in nursing care (5,(9)(10) .
The objective of this study was to evaluate the efficacy of a LA protocol, developed and applied by nurses in patients with SAH. This study was based on the hypothesis that the application of AP as a technology for nursing care promotes a significant decrease in blood pressure levels in hypertensive patients undergoing drug treatment and who find difficulties for the effective control of blood pressure.

Methodology
A randomized, multicenter, controlled, triple-blind and two-armed clinical trial with a random assignment rate set at 50% per arm. This study was performed at The random assignment was performed by block in a ratio of 1:1, using an outsourced service for the random assignment through the internet (http://www. sealedenvelope.com).
The number assigned to the participants was entered into the system that automatically generated their assignment in one of the study arms, without the interference of participants, ensuring equal and independent inclusion chances, that is, both in Arm A -Intervention (acupuncture) and in Arm B -Control

Results
In total, each arm consisted of 51 participants,  There was a higher reduction of the sample among women in arm B (simulation), which had a reduction of 33.3% (n=12) when compared to the same gender in arm A (intervention), whose reduction was 14.7 % (n=5).
In the period from August to September 2015, an interim analysis was performed considering 79 participants in total. On that occasion, 23 losses were observed in total, which did not compromise the    Table 2.
By comparing the moments between 1 and 6, it was observed a significantly higher variation in BP reduction in arm A than that observed in arm B. These results are shown in Table 3.
No undesirable effects or adverse events that required the need to exchange participants between groups or compromised the quality of the study were identified or reported.

Discussion
This study confirmed the hypothesis that AP, combined with drug treatment, has efficacy in the acute control of BP in patients with difficulty controlling their blood pressure levels. In the intervention arm, blood pressure dropped to levels below 140x90 mmHg, which may contribute significantly to the non-aggravation of the disease, as demonstrated in studies using other therapies for BP control (7,(11)(12)(13) .
The technique proposed in this study, combined with drug treatment strategies, complemented the conventional treatment, confirming the potential of AP as an integrative and complementary health therapy, not as a substitute or alternative method to the current treatment models.
It is considered that nurses specialized in AP, by incorporating it as a nursing care technology, may help hypertensive patients to effectively control their BP, since its use helps to achieve the therapeutic goal for BP.
This favors the minimization of risks and comorbidities, since the effective control of BP levels helps reducing cardiovascular risk, especially in non-diabetic hypertensive patients without renal disease (13)(14)(15) .
The observed decrease in both SBP and DBP was significant from a statistical point of view. Studies using other protocols and traditional AP techniques have shown better results in the reduction of SBP, although DBP was also benefited (7,(15)(16) .
Results showing an improvement in BP values, but with a very small reduction in its levels, as observed in Arm B (Table 2), were also noticed in control groups of other studies in which AP was used (14)(15) . It is believed that this may be related to the posture adopted by the participants during the course It should be noted that longitudinal effects, after discontinuation of therapy, have not yet been addressed, which is a limiting factor of this research for generalizing the results, a similar situation also found in other studies on the efficacy of the method (14)(15) . given the need to prove the efficacy of these techniques.
In this context, in order to overcome the aforementioned limitation and, at the same time, contemplate the fundamental characteristics of the RTC When participants with physical activity habits and on programmed diets for weight loss were considered as exclusion criteria, a possible bias in the reduction of BP produced by physical activity habits and weight loss was avoided. Similar strategies were observed in clinical trials analyzed in systematic review studies that investigated the use of AP for the treatment of SAH (6,15) .
Participants' body weight and body mass index were investigated at initial and final nursing consultations and no significant changes were observed that could contribute to BP alterations. The same reasoning was used for the exclusion of smokers and alcoholics, considering that possible interruption of smoking and alcohol consumption could interfere in the reduction of blood pressure levels.
The exclusion of the use of other CIP by participants during the intervention phase was also considered in order to avoid possible bias, as the use of other CIP, concomitant with drug treatment, may also influence the BP levels, just like LA (17)(18) . This was not observed in the participants of both arms who used the proposed therapy as the only CIP.
The limitations of this study include the difficulty in controlling participants' lifestyles, the sample losses that occurred throughout the study related to personal issues of participants, the non-measurement of responses to therapy in a longer time interval and/or less regularity in the performance of the interventions, and the effectiveness of the results achieved after therapy discontinuation.
However, these limitations did not compromise the quality of the study and the obtained results.
Therefore, it is considered that the results observed

Conclusion
Based on the results, it was possible to confirm the efficacy of the protocol. There was an acute reduction and a significant BP control in all participants of arm A during the intervention period, indicating the possibility of using this technology in the care of hypertensive patients.
In order to further deepen and better understand the results of the protocol in a long term, as well as the improvement of BP levels after its discontinuation and other clinical benefits, it is recommended that further studies be conducted.