J Orofac Pain 30 (2016), No. 4 28. Oct. 2016
J Orofac Pain 30 (2016), No. 4 (28.10.2016)
Genetic Polymorphisms of Catechol-O-Methyltransferase: Association with Temporomandibular Disorders and Postoperative Pain
Mladenovic, Irena / Supic, Gordana / Kozomara, Ruzica / Dodic, Slobodan / Ivkovic, Nedeljka / Milicevic, Bojana / Simic, Ivana / Magic, Zvonko
Aims: To evaluate the association between catechol-O-methyltransferase (COMT) gene polymorphisms and temporomandibular disorders (TMD), TMD pain, psychosocial impairment related to TMD, and postoperative pain.
Methods: A total of 90 patients with a diagnosis of painful TMD and 92 matched controls were investigated for the presence of TMD, TMD pain, and psychosocial variables by the Research Diagnostic Criteria for TMD. In a prospective cohort study of 40 subjects who underwent extraction of at least one fully impacted mandibular third molar, subjects had 6 months post-surgery follow-up of postoperative pain. DNA extracted from peripheral blood was genotyped for three COMT polymorphisms (rs4680, rs6269, and rs165774) by real-time TaqMan method. The association between COMT polymorphisms and clinical variables was determined by calculating odds ratios (OR) and their 95% confidence intervals (CI).
Results: Homozygous AA genotype and heterozygous variant A allele carriers (genotype AG/AA) for rs165774 polymorphism were associated with increased risk of TMD compared to wild type (wt) GG genotype (OR = 9.448, P = .006; OR = 2.088, P = .017, respectively). In addition, AA genotype was associated with increased risk of arthralgia (OR = 4.448, P = .011), myofascial pain (OR = 3.543, P = .035), and chronic TMD pain (OR = 6.173, P = .006), compared to wt genotype. AA genotype for rs6269 polymorphism was related to less postoperative chronic TMD pain (P = .025) and lower postoperative acute pain at the extraction site (P = .030). No associations with depression and somatization were observed.
Conclusion: AA genotype of rs165774 could be a significant risk factor for the development of TMD and TMD pain, while AA genotype of rs6269 presents less postoperative chronic TMD pain and acute pain at a dental extraction site.
Keywords: COMT, genetic polymorphisms, pain, temporomandibular disorders, third molar surgery