A Case-control Study On Acupoint Hyperalgesia In Patients With Chronic Stable Angina Pectoris

Objective:By comparing the acupoint tenderness threshold of patients with chronic stable angina pectoris(CSAP)and healthy people,to explore the characteristics and distribution pattern of acupoint tenderness sensitization in CSAP,to discuss the relevance between the tenderness sensitization and CSAP,and to provide the reference to the acupuncture treatment for CSAP with sensitized acupoints.Method:In this trial,a case-control study method of clinical epidemiology was used to examine the meridian points and sensitive points of 323 eligible participants including 197 CSAP patients and 126 healthy subjects in Chengdu,and manual pressure and pressure pain threshold(PPT)was detected using the WANGNER tenderness instrument.13 CSAP related acupoints,such as PC6,HT7,etc.,was selected,and sensitive points were detected in hand,chest and back.Count the number of sensitive points and analyze the measured values of PPT to observe the change characteristics of CSAP patients compared with healthy subjects;Use ROC curve method to calculate the tenderness sensitization rate of each meridian point to determine whether the acupoints are sensitized,and to summarize whether the tenderness sensitization of CSAP patients is universal.Explore the spatial distribution characteristics by integrating and calculating average measurement value of acupoints in different meridians and locations.And logistic regression was used to analyze the correlation of tender sensitization with age,gender and VAS score during angina.Result:1.Comparison of CSAP patients and healthy subjects with acupoint manual pressure.All the rates of acupoints manual pressure sensitivity in CSAP patients are higher than healthy subjects.The top three points with manual pressure sensitive difference rate were PC6(34.06%),BL15-L(32.83%),BL15-R(29.80%).2.Analysis of acupoint PPT of CSAP patients and healthy subjects.(1)The PPT of all acupoints in CSAP patients was lower than that in healthy subjects(p<0.001),which indicated that CSAP patients are characterized by a decrease in pressure pain threshold.(2)The result of analyzing cut-off value to determine diagnostic acupoint sensitization by the approach of ROC curve showed that the cut-off values of PC3,PC6,HT3,HT6,PC4,CV14,HT1,BL15-R and BL14-R were better,AUC>0.7,and Youden index >0.32.(3)The tenderness sensitization rate of all acupoints in CSAP patients was higher than that in healthy subjects(p<0.001).The tenderness sensitization rate of CSAP patients is 50%-90%,and the top five are HT1,HT3,PC6,HT6,HT7.The tenderness sensitization difference rate of most acupoints is more than 30%,and the top three are PC6,HT6,HT3.3.The spatial distribution characteristics of tenderness sensitization with CSAP patients.(1)The tenderness sensitization rate of different parts of the body was the highest in upper arm,up to 81.63%,and the lowest in back was 53.57%.The sensitization difference rate was the highest in upper arm,up to 41.15%,and the lowest in back was 28.17%.(2)The tenderness sensitization rate of different meridians was the highest in Shaoyin Heart Meridian of Hand,up to 85.20%,and the lowest in Taiyang Bladder Meridian of Foot was 53.57%.The sensitization difference rate was the highest in Jueyin Pericardium Meridian of Hand,up to 47.33%,and the lowest in Taiyang Bladder Meridian of Foot was 28.17%.(3)Distribution characteristics of sensitive points in different regions: The PPT of the sensitive points on the back is higher than that on the hand and chest.Arm is characterized with the most sensitive points in upper arm,accounting for 64.35%.Chest is characterized that sensitive points in upper part of horizontal line of nipple is higher than that in lower part,accounting for 74.79%.And back is a character with the distribution of more sensitive points between the both sides of the T1-T3 scapula and between the horizontal line of the T3-T5 spinous.It shows a “? type" regional distribution,and the total proportion of 61.50%.The tenderness sensitization rate is ranked from high to bottom as: upper arm >forearm >back > chest;the arm ulnar side > radial side.4.Analysis of relevant factors affecting tenderness sensitization of acupoints.The age,gender and VAS score were included in the logistic regression to analyze the correlation between tenderness sensitization and related factors.Sex is the factors influencing the sensitization of PC4(OR=0.388,P=0.017),PC3(OR=0.420,P=0.023),CV17(OR=0.370,P=0.010)and CV14(OR=0.447,P=0.014),and the sensitization rate of female is higher than male.VAS score is the factors influencing the sensitization of PC4(OR=0.834,P=0.031)and PC3(OR=0.834,P=0.028),and patients with the lower score has a higher sensitization rate.Conclusion:1.Compared with healthy subjects,all acupoints of CSAP patients show an increased manual pressure sensitivity,a decreased pressure pain threshold and an increased tenderness sensitization rate,which indicated that acupoint tenderness sensitization was universal.2.PC6 shows a both highest manual pressure sensitive difference rate and tenderness sensitization difference rate,indicating that there is a most specific relationship between CSAP tenderness sensitization and PC6,so PC6 may be the dominant sensitizing acupoint of CSAP.3.The spatial distribution characteristics of tenderness sensitization with CSAP patients is related to the meridian it belongs and location of acupoint.The Heart Meridian and Pericardial Meridian are more prone to tenderness sensitization than Conception Vessel and Bladder Meridian.The arm is more prone to tenderness sensitization than chest and back.The ulnar side of the arm is more prone to tenderness sensitization than the radial side.And the "? type" area between T1-T5 spinous process on the back is more prone to tenderness sensitization.4.The acupoint tenderness sensitization in CSAP patients may be related to gender and VAS score during angina.Female and patients with a lower VAS score are more susceptible to sensitization.