A single-nucleotide polymorphism in SCN9A may decrease postoperative pain sensitivity in the general population.
BACKGROUND
This study aimed to explore the role of a nonsynonymous single-nucleotide polymorphism, 3312G>T, in SCN9A, which was identified in probands with congenital indifference to pain, but which is also present in normal controls, in the prediction of individual baseline pain perception, and postoperative pain sensitivity in the general population.


METHODS
Preoperative pressure pain thresholds and tolerance were measured in 200 patients undergoing pancreatectomy, and the postoperative pain sensitivity and analgesic demand were recorded. These variables were compared according to the SCN9A 3312G>T alleles. Logistic regression analysis was used to test the role of preoperative variables in the prediction of postoperative inadequate analgesia.


RESULTS
The 3312Tallele was present in 22 individuals, and the 3312Tallele frequency was 5.5% (22/200). The average patient-controlled analgesia pressing frequency and opioid consumption in 3312G patients was significantly higher than those in 3312T patients (2.70 [SD: 0.84] vs. 2.05 [SD: 0.43], P < 0.001; 100.8 [SD: 40.7] vs. 74.8 [SD: 20.8] ml, P = 0.006). The incidence of inadequate analgesia in 3312G patients was significantly higher than that of patients carrying the 3312Tallele (29.2% vs. 4.5%; P = 0.013). Carrying the 3312Tallele and having a higher pressure pain threshold predicted a lower risk of postoperative inadequate analgesia, with an odds ratio of 0.10 (95% CI: 0.01 to 0.76, P = 0.026) and 0.32 (95% CI: 0.13 to 0.82, P = 0.018), respectively.


CONCLUSIONS
Patients carrying the SCN9A 3312Tallele presented with lower postoperative pain sensitivity in the presence of a similar surgical pain stimulus, and had a lower likelihood of developing inadequate analgesia than those carrying the 3312Gallele.
Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Guangyou
G
Duan
Guifang
G
Xiang
Xianwei
X
Zhang
Ruimei
R
Yuan
Huiming
H
Zhan
Dongmei
D
Qi
D000328:Adult; D000367:Age Factors; D000368:Aged; D000698:Analgesia; D000758:Anesthesia; D005260:Female; D005787:Gene Frequency; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D062556:NAV1.7 Voltage-Gated Sodium Channel / Q000235:genetics*; D000699:Pain Insensitivity, Congenital / Q000235:genetics*; D010147:Pain Measurement; D058748:Pain Perception / Q000502:physiology; D017288:Pain Threshold / Q000502:physiology; D010149:Postoperative Pain / Q000453:epidemiology / Q000235:genetics*; D010180:Pancreatectomy; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011300:Preoperative Care; D011312:Pressure; D055815:Young Adult
D062556:NAV1.7 Voltage-Gated Sodium Channel; C486866:SCN9A protein, human