Influence of Psychological Factors on Risk of Temporomandibular Disorders

TLDR

Psychological traits may cause or result from temporomandibular disorder. The study tested whether pain‑sensitive psychological traits predict first‑onset TMD and whether this association is mediated by COMT genotype. A prospective cohort of 171 healthy women aged 18–34 was genotyped for COMT, surveyed for psychological traits, and assessed for pain sensitivity at baseline. Over up to three years, 8.8% developed TMD, and depression, stress, and mood were linked to pain sensitivity and doubled or tripled TMD risk, an association that remained after adjusting for COMT genotype.

Abstract

Psychological characteristics potentially may be a cause or consequence of temporomandibular disorder (TMD). We hypothesized that psychological characteristics associated with pain sensitivity would influence risk of first-onset TMD, but the effect could be attributed to variation in the gene encoding catechol- O-methyltransferase (COMT). We undertook a prospective cohort study of healthy female volunteers aged 18–34 yrs. At baseline, participants were genotyped, they completed psychological questionnaires, and underwent quantitative sensory testing to determine pain sensitivity. We followed 171 participants for up to three years, and 8.8% of them were diagnosed with first-onset TMD. Depression, perceived stress, and mood were associated with pain sensitivity and were predictive of 2- to 3-fold increases in risk of TMD (P < 0.05). However, the magnitude of increased TMD risk due to psychological factors remained unchanged after adjustment for the COMT haplotype. Psychological factors linked to pain sensitivity influenced TMD risk independently of the effects of the COMT haplotype on TMD risk.