Electro-acupuncture resulted in significant improvement in pain and function, compared with sham acupuncture, in a randomized trial of more than 400 adults with knee OA.
The socioeconomic burden of knee OA (KOA) remains high, and will likely increase with the aging population and rising rates of obesity, wrote first author Jian-Feng Tu, MD, PhD, of Beijing University of Chinese Medicine and colleagues. “Since no disease-modifying pharmaceutical agents have been approved, current KOA treatments are mainly symptomatic,” and identifying new therapies in addition to pharmacological agents or surgery is a research priority, they added. The research on acupuncture as a treatment for KOA has increased, but remains controversial as researchers attempt to determine the number of sessions needed for effectiveness.
In a study published in Arthritis & Rheumatology, the researchers recruited 480 adults aged 45-75 years with confirmed KOA who reported knee pain for longer than 6 months. Participants were randomized to three groups: electroacupuncture (EA), manual acupuncture (MA), or sham acupuncture (SA). Each group received three treatment sessions per week. In all groups, electrodes were attached to selected acupuncture needles, but the current was turned on only in the EA treatment group.
The primary outcome was the response rate after 8 weeks of treatment, defined as patients who achieved the minimal clinically important improvement (MCII) on both the Numeric Rating Scale and the Western Ontario and McMaster Universities Osteoarthritis Index function subscale.
Overall, response rates at 8 weeks were 60.3%, 58.6%, and 47.3% for the EA, MA, and SA groups, respectively.
Between-group differences were statistically significant for EA versus SA (13%, P = .0234) but not for MA versus SA (11.3%, P = .0507) at 8 weeks; however, both EA and MA groups showed significantly higher response rates, compared with the SA group at 16 and 26 weeks. “Although a clinically meaningful response rate for KOA is not available in the literature, the difference of 11.3%, which indicates the number needed to treat of 9, is acceptable in clinical practices,” the researchers noted.
Adverse events occurred in 11.5% of the EA group, 14.2% of the MA group, and 10.8% of the SA group, and included subcutaneous hematoma, post-needling pain, and pantalgia. All adverse events related to acupuncture resolved within a week and none were serious, the researchers wrote.
The study findings were limited by several factors, including the potential burden on patients of three sessions per week, the limited study population of patients with radiologic grades of II or III only, the use of self-reports, and the lack of blinding for outcome assessors, the researchers noted.
However, the results show persistent effects in reducing pain and improving function with EA or MA, compared with SA, the researchers wrote. The findings were strengthened by “adequate dosage of acupuncture, the use of the primary outcome at an individual level, and the rigorous methodology.” The use of the MCII in the primary outcome “can provide patients and policy makers with more straightforward information to decide whether a treatment should be used.”
Optimal Dosing Questions Remain
Current options for managing KOA are limited by factors that include low efficacy and unwanted side effects, while joint replacements increase the burden on health care systems, wrote David J. Hunter, MBBS, PhD, of the University of Sydney, and Richard E. Harris, PhD, of the University of Michigan, Ann Arbor, in an accompanying editorial. “In this context, development of new treatments or identification of efficacy of existing therapies to address the huge unmet need of pain are strongly desired.” Acupuncture continues to gain popularity in North and South America, but its efficacy for pain and KOA remain controversial.
The question of dose is challenging when assessing acupuncture because the optimal dose and how to classify it remains unknown. “In this study, the authors used three treatments a week, which is more frequent than typical studies done in the West and potentially may not be feasible in some health care settings. A recent systematic review suggests that treatment frequency matters and a dose of three sessions per week may be superior to less frequent treatment,” they emphasized. Acupuncture is generally considered to be safe, but many health systems do not reimburse for it. Patients may have large out-of-pocket expenses because of the number of visits required, which may be a barrier to further implementation in practice.
“Acupuncture is already widely practiced and readily available in many countries and health care systems,” the editorialists said. However, “more research is needed in the areas of dose-response relationships, effects of blinding the acupuncturist, feasibility of three times weekly regimens, and clarifying the mechanism of effect, particularly given the persistence of benefit.”
The study was funded by Beijing Municipal Science & Technology Commission and Beijing Municipal Administration of Hospitals. The researchers had no financial conflicts to disclose. Hunter disclosed support from a National Health and Medical Research Council Investigator Grant and providing consulting advice for Merck Serono, TLC Bio, Tissuegene, Lilly, and Pfizer.
SOURCE: Tu J-F et al. Arthritis Rheumatol. 2020 Nov 10. doi: 10.1002/art.41584.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.