Correlation of electrical conductance in meridian and autonomic nervous activity after auricular acupressure in middle-aged women

Background: This study aimed to examine the correlation of heart rate variability (HRV) and meridian electrical conductance among middle-aged women during an 8-week period of auricular acupressure (AA) treatment for weight reduction. Methods: Sixty (60) subjects were randomized either to a control group (n=30) or to a treatment group with AA (n=30). Anthropometric parameters, HRV indices, and meridian levels were measured before treatment, at the 5th week, and 1 week after the 8-week treatment period. Results: Although no significant changes were observed in body weight (BW) and body-mass index (BMI) from baseline to 1 week after AA treatment, a significant decrease in Waist Circumference (WC) was observed in the acupressure group. In contrast, the subjects' BW, BMI, and WC were significantly increased from baseline to the 9th week in the control group. With adjustment for baseline low frequencies (LF) of HRV, the LF at the 5th and 9th weeks in the acupressure groups was generally lower than that in the control group, with a p-value=0.027 using the mixed linear model. The meridian levels for Spleen, Bladder, and Gallbladder were significantly lower in the group subjected to acupressure than in the control group at the 5th week. Conclusions: The results of the present study indicate that AA tends to inactivate the sympathetic nervous activity demonstrated by both HRV and meridian electrical conductance changes. As a result, AA may modulate the autonomic nervous system to exert its physiological effect through the pathway of the meridian system.