Part 1: This study will include 40 patients with MDD and 40 healthy control participants. Infrared thermography (IRT), laser doppler flowmetry (LDF), functional near-infrared spectroscopy (FNIS), and digital pressure pain gauge (PPG), respectively, will be adopted to assess 4 kinds of biological specificity of MDD related acupoints, namely, the thermal transport specificity, the microcirculatory specificity, the metabolic specificity, and the pain sensitivity specificity. Based on the results of this study, we will select acupoints with statistical differences between the two groups as the strong reaction acupoints and the remaining acupoints as the weak reaction acupoints.~Part 2: A total of 120 participants with MDD who meet the inclusion criteria will be included in the study. All participants will receive basic treatment of selective serotonin reuptake inhibitors (SSRIs) antidepressants. They will be randomly divided into the acupuncture (strong reaction acupoints) group, acupuncture (weak reaction acupoints) group, and sham acupuncture group. We will evaluate the therapeutic effect and safety of acupuncture for MDD, furthermore, to demonstrate whether stimulating strong reaction acupoints has more advantages in the treatment of MDD than weak reaction acupoints.
Acupoints are the stimulus points and reactive points for acupuncture to treat the diseases. Therefore, this study is designed to detect the biological specificity of acupoints in healthy participants and major depressive disorder (MDD) participants by using multiple objective assessment tools. And then acupoints that are statistically different between the two groups will be defined as strong reaction points, and other acupoints without statistically different will be defined as weak response points. In addition, this clinical trial will be conducted to explore whether the efficacy of stimulating strong reaction acupoints is more effective than weak reaction points, thereby confirming the specificity of the acupoint.