Effect of Acupuncture on the Motor and Nonmotor Symptoms in Parkinson's Disease — A Review of Clinical Studies

This comprehensive review examined 15 years of clinical research on the use of acupuncture in the treatment of Parkinson's disease (PD), analyzing data from 519 patients across 14 clinical studies. Parkinson's disease is a progressive neurodegenerative disorder that affects more than 1 in 1,000 people over age 60, characterized not only by motor symptoms such as tremor and rigidity but also by a broad range of nonmotor symptoms that frequently precede the motor symptoms and have a more profound impact on patients' quality of life. The review included studies conducted in the United States, Korea, and China, using rigorous selection criteria focused on penetrating acupuncture with manual or electrical stimulation. Results revealed that acupuncture, both manual and electroacupuncture, demonstrated significant efficacy in relieving motor symptoms of PD.

Seven studies used the Unified Parkinson's Disease Rating Scale (UPDRS), with four showing moderate to marked improvement in UPDRS III motor scores. Notably, one study using functional magnetic resonance imaging demonstrated that stimulation of point GB-34 activated movement-related brain regions, including the putamen and primary motor cortex, providing neurobiological evidence of the mechanism of action of acupuncture. Nonmotor symptoms showed an even more impressive response to acupuncture treatment. Depression, one of the most common and debilitating nonmotor symptoms of PD, showed significant improvement in all studies that evaluated it, with consistent reduction in Beck Depression Inventory scores.

Sleep disturbances, which affect up to 50% of PD patients, also responded favorably, with 85% of patients reporting subjective improvement in sleep problems. Gastrointestinal symptoms, particularly constipation and nausea, showed substantial improvement without adverse effects. Bladder dysfunction, another common autonomic symptom, also showed significant improvement with acupuncture treatment. A clinically relevant finding was that when acupuncture was used as an adjunct to levodopa, it not only improved therapeutic efficacy but also allowed for reduction of dosage and decrease in medication side effects.

Some studies reported that up to 87% of patients were able to interrupt medication for two weeks after acupuncture treatment, while maintaining good symptom improvement. The most frequently used acupuncture points were GB-34 (Yanglingquan), ST-36 (Zusanli), LR-3 (Taichong), and KI-3 (Taixi), with about 40 different body points employed across the various studies. The technique called 'Seven Points at the Base of the Skull' (GV-15, bilateral BL-10, GB-20, and GB-12) showed particularly promising results. However, the review identified significant methodological limitations that restrict the reliability of the results.

Eight of the 14 studies did not present adequate diagnostic criteria, only two were single-blind controlled studies, and only one was double-blind controlled. Lack of appropriate control groups, small sample sizes, and inconsistency in outcome measures were recurrent problems. In addition, most studies did not mention adverse effects or dropouts during treatment. Duration and frequency of treatment varied considerably across studies, suggesting that standardized protocols are needed.

Despite these limitations, the data suggest that acupuncture has promising therapeutic potential for PD, especially for nonmotor symptoms that respond poorly to conventional dopaminergic treatment. Clinical implications include the possibility of using acupuncture as adjunctive therapy to improve patients' quality of life and potentially reduce dependence on medications. The authors recommend that future studies follow rigorous methodological guidelines, include adequate sample sizes based on appropriate pilot studies, use standardized outcome measures, and include follow-up assessments to determine the sustainability of therapeutic effects. Comparative-effectiveness research and high-quality placebo-controlled studies are needed to definitively establish the role of acupuncture in the management of Parkinson's disease.