Can acupuncture therapy reduce preoperative anxiety? A systematic review and meta-analysis

Preoperative anxiety is an extremely common emotional condition that affects nearly every patient who is about to undergo any type of surgery. This natural response of the body to a stressful situation can interfere not only with the patient's emotional well-being but can also directly influence surgical success, the effects of anesthesia, and postoperative recovery. Studies show that only about 7% to 8% of patients experience no anxiety before surgery, with this tension tending to peak in the preoperative holding area before the procedure. Traditionally, anxiolytic medications have been used to control this anxiety; however, they frequently cause unwanted side effects, including nausea, vomiting, and postoperative pain, which can delay recovery and reduce patient satisfaction.

Against this backdrop, interest has grown in non-pharmacologic therapeutic alternatives, particularly acupuncture, which has shown potential to reduce preoperative anxiety without the adverse effects of conventional medications.

The primary objective of this study was to evaluate rigorously and systematically whether acupuncture can actually reduce anxiety in patients before surgery, analyzing both its efficacy and safety. To this end, the researchers conducted a meta-analysis, a type of study that combines and analyzes the results of multiple prior studies on the same topic, allowing more robust and reliable conclusions to be drawn. The methodology involved a comprehensive search of seven major scientific databases, including Chinese and Western databases, from their inception through February 2020. Keywords related to acupuncture, preoperative procedures, and anxiety were used.

Inclusion criteria were strict: only randomized controlled trials involving adult patients with preoperative anxiety, comparing various forms of acupuncture with control groups that received sham acupuncture or routine care. Acupuncture techniques considered included traditional acupuncture, electroacupuncture, auricular acupuncture, and electrical stimulation at specific points. The researchers assessed the quality of the studies and analyzed the data using specialized software, also applying the GRADE system to assess the quality of scientific evidence.

The final analysis included twelve studies conducted in six different countries, involving a total of 916 patients, with 460 in the group that received acupuncture and 456 in the control group. The types of surgery varied widely, including neurologic, gynecologic, orthopedic, cardiac, and other procedures. The results showed that acupuncture was effective at significantly reducing anxiety as measured by two specific scales: the State-Trait Anxiety Inventory and the Visual Analog Scale. On the first scale, patients who received acupuncture had a mean reduction of 9.07 points compared with the control group, while on the second scale the reduction was 1.37 points.

These results indicate a clinically relevant improvement in patient anxiety. By contrast, when anxiety was measured with the Hamilton Anxiety Scale, there was no statistically significant difference between groups. As for side effects, acupuncture was found to be very safe: four of the five studies reporting adverse events found no untoward reactions, and in one study the acupuncture group had less postoperative nausea and vomiting compared with the control group.

For patients facing the prospect of surgery, these results are encouraging, suggesting that acupuncture may be a safe and effective option for reducing preoperative anxiety, without the risks associated with medications. For healthcare professionals, the study offers scientific evidence that can guide clinical decisions, particularly in situations where one wishes to avoid the use of sedative medications or when patients prefer more natural approaches. Acupuncture can be readily integrated into preoperative preparation protocols, being administered by qualified clinicians within the hospital setting itself. The results also suggest that different acupuncture techniques may be effective, offering flexibility in choosing the most appropriate treatment for each specific situation.

In addition, the fact that acupuncture does not interfere with anesthetic medications or other medical procedures makes it a viable complementary option.

However, it is important to acknowledge the limitations of this study. The quality of the scientific evidence was rated only moderate for one of the anxiety scales and low for another, indicating that more rigorous research is still needed. The studies analyzed showed considerable variation in the acupuncture techniques used, the points selected for needling, and the duration of treatments, which makes it difficult to determine which approach is most effective. Many of the included studies did not adequately describe their methods of randomization and blinding, aspects that are fundamental to ensuring the reliability of the results.

In addition, the number of participants in each individual study was relatively small, and the variety of surgery types included may have influenced the results. The authors emphasize that, although the results are promising, more research with more rigorous methodological designs and larger numbers of participants is needed to definitively confirm the efficacy of acupuncture in treating preoperative anxiety.