A Pilot Randomized, Single Blind, Placebo-Controlled Trial of Traditional Acupuncture for Vasomotor Symptoms and Mechanistic Pathways of Menopause

This pilot randomized controlled trial investigated the effects of traditional acupuncture on menopausal vasomotor symptoms and possible mechanisms of action through the hypothalamic-pituitary-adrenal axis. The research context arises from the need for non-hormonal alternatives to treat menopausal symptoms, particularly after the Women's Health Initiative findings raised concerns about the risks of hormone therapy. Vasomotor symptoms, experienced by 68-82% of women during the menopausal transition, are the primary reason for seeking treatment, but available pharmacological options have limited efficacy and undesirable side effects. The methodology involved 33 peri- and postmenopausal women with at least 7 daily hot flashes, equally randomized into three groups: traditional acupuncture, sham acupuncture, and wait-list control.

The intervention period was 12 weeks, with participants in the acupuncture groups receiving treatment three times per week, totaling up to 36 sessions. The traditional acupuncture group used a standardized protocol with 11 frontal points and 7 dorsal points, alternated between sessions, with needling depth of 0.5 to 1.5 inches and manual stimulation to achieve the 'de-qi' (得气) sensation. Sham acupuncture used adjacent points considered inactive, with manipulation but without skin penetration. Primary outcomes included 7-day hot flash diaries, the MENQOL quality of life questionnaire, and psychosocial measures such as anxiety, depression, and sleep quality.

Innovatively, the study investigated the hypothalamic-pituitary-adrenal axis through 24-hour urine collection and an ACTH stimulation test. Findings revealed that both traditional and sham acupuncture demonstrated trends of improvement in vasomotor symptoms compared with the wait-list control, with frequency reductions of -3.5 ± 3.00 vs. -4.1 ± 3.79 vs. -1.2 ± 2.4, respectively.

Significantly, both acupuncture groups showed improvement in MENQOL vasomotor scores (p=0.04). There were no between-group differences in psychosocial measures. However, the most intriguing results emerged from the hypothalamic-pituitary-adrenal axis analyses. The traditional acupuncture group had significantly lower levels of total urinary cortisol metabolites (p=0.03) and DHEA (p=0.05) compared with the other groups.

In addition, a correlation was observed between improvement in urinary cortisol levels and reduction in hot flash frequency only in the traditional acupuncture group (r=0.62, p=0.043). The clinical implications are multifaceted. Although both real and sham acupuncture improved subjective symptoms, suggesting a placebo component, only traditional acupuncture affected objective markers of the hypothalamic-pituitary-adrenal axis. This suggests that traditional acupuncture may operate through specific physiological mechanisms beyond psychological effects.

The identification of the HPA axis as a potential mechanistic pathway opens new therapeutic perspectives, including potential use of selective serotonin reuptake inhibitors or other cortisol modulators. Limitations include the small sample size characteristic of pilot studies, heterogeneity of the studied population, reliance on subjective measures of vasomotor symptoms, and high dropout rate. The lack of objective hot flash measures, such as skin conductance monitoring, represents an important limitation that should be addressed in future studies. The authors acknowledge that the findings should be considered preliminary and hypothesis-generating, requiring confirmation in larger and more rigorous clinical trials.