[Effect of umbilical moxibustion on intestinal flora in patients with subthreshold depression]

To observe the clinical efficacy of umbilical moxibustion for subthreshold depression (SD) and its effect on intestinal flora, and to explore its mechanism.

Thirty-six SD patients were recruited as the SD group (1 case dropped out, 2 cases excluded), and 36 healthy subjects were recruited as the healthy control group (1 case excluded). The SD group was treated with umbilical moxibustion, once a week, a total of 8 times were required. The healthy control group did not receive any intervention. Hamilton depression scale 17-item (HAMD-17) and Center for Epidemiologic Studies depression scale (CES-D) scores were observed in the SD group before and after treatment, and the clinical efficacy was evaluated. Fecal samples were collected in the SD group before and after treatment and in the healthy control group when enrolled, the intestinal flora was analyzed by 16S rRNA sequencing technology.

The HAMD-17 and CES-D scores after treatment in the SD group were reduced compared with those before treatment (P<0.05), and the total effective rate was 90.9% (30/33). Compared with the healthy control group, Sobs index, Shannon index and Ace index were reduced in the SD group before treatment (P<0.05), Simpson index was increased (P<0.05), the relative abundance of Escherichia-Shigella was increased (P<0.01), the relative abundance of Eubacterium_hallii_group, Ruminococcus, Christensenellaceae_R-7_ group, Paraprevotella was decreased (P<0.05, P<0.01). Compared before treatment, the relative abundance of Escherichia- Shigella after treatment in the SD group was decreased (P<0.01), the relative abundance of Ruminococcus, Christensenaceae_R-7_group, Paraprevotella was increased (P<0.01, P<0.05). Christensenellaceae_R-7_group and Paraprevotella were negatively correlated with the CES-D score (P<0.01, P<0.05). Escherichia-Shigella was positively correlated with the HAMD-17 score (P<0.05). Christensenellaceae_R-7_group was negatively correlated with the HAMD-17 score (P<0.01).

Patients with subthreshold depression have dysbiosis of intestinal flora, and umbilical moxibustion may exert therapeutic effect by regulating the abundance and diversity of intestinal flora, increasing beneficial bacteria, and reducing harmful bacteria.