[Rule of acupoint combination in acupuncture treatment of hiccup: a study based on complex network analysis]

To explore the rule of acupoint combination in acupuncture treatment of hiccups.

Original research articles on acupuncture treatment of hiccup were collected from databases of CNKI, Wanfang, VIP, and Pubmed by using key words of "hiccup", "acupuncture" "diaphragmatic spasm" "body acupuncture" "filiform needle" and "electroacupuncture". According to our inclusive and exclusive criteria, the collected data were extracted to establish an acupuncture prescription database for hiccup. Then, the regularities of acupoint combinations for hiccup were analyzed by using Gephi complex network analysis software.

;A total of 606 articles containing 634 acupoint prescriptions for acupuncture treatment of hiccups were brought into analysis. There were 133 single-acupoint prescriptions (20.98%), which was significantly lower than the multi-acupoint prescription (501, accounting for 79.02%). There were mainly acupoints in multi-acupoint prescriptions, and distal-proximal acupoint combination method were often used as the basis of acupoint selection (326, accounting for 65.07%). A total of 163 acupoints were involved, with a total frequency of 2 969. Among them, Neiguan(PC6) was used most frequently (400 times, accounting for 13.47%), followed by Zusanli (ST36), Zhongwan (CV12), Danzhong (CV17), and Taichong (LR3). The acupoints of the Conceptional Vessel(666 times, accounting for 22.43%), and Stomach Meridian, Pericardium Meridian and Liver Meridian were chiefly used. There were 67 specific acupoints, the frequency of use was 2 555 times(accounting for 86.05% of the total frequency), among which the frequency of the five Shu-points was the highest (875 times, accounting for 29.47% of the total frequency), and followed by eight confluence points.

;The core acupoints are PC6, ST36, CV12, etc. and the distal-proximal acupoint combination method found in this study are often used as the basis of acupoint selection and acupoint prescription for acupuncture treatment of hiccup.