title: General health status and incidence of first-onset temporomandibular disorder: the OPPERA prospective cohort study.
abstract: Temporomandibular disorder (TMD) overlaps with other health conditions, but no study has examined which of these conditions increase the risk of developing first-onset TMD. The authors prospectively evaluated the relationship between health status at enrollment and subsequent incidence of TMD in 2,722 men and women. Participants aged 18 to 44 years had no history of TMD and were clinically free of TMD when enrolled in 2006 to 2008 at 4 U.S. study sites in the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) prospective cohort study. First-onset examiner-classified TMD developed in 260 people over a median 2.8 years of follow-up. Cox regression estimated the association between health conditions and TMD incidence while accounting for potential confounders. Incidence of first-onset TMD was 50% higher for people with low back pain (adjusted hazard ratio [AHR] = 1.50, 95% confidence limits [CLs]: 1.08, 2.10) and 75% higher for people with genital pain symptoms (AHR = 1.75, 95% CLs = 1.04, 2.93) than people without a history of these pain disorders. Digit ratio, a marker of intrauterine exposure to sex hormones, was significantly associated with TMD incidence. Other independent predictors of first-onset TMD were sleep disturbance and cigarette smoking. These findings reveal multiple influences of health status on incidence of first-onset TMD.
  
  
  CONCLUSIONS
  This article examines health conditions that commonly overlap with TMD to determine which ones predict first-onset TMD. A history of low back pain and genital pain conditions at baseline were important predictors. Novel findings were that disrupted sleep and conditions in utero may increase incidence of first-onset TMD.
authors.affiliation: Regional Center for Neurosensory Disorders, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Department of Dental Ecology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Electronic address: anne_sanders@dentistry.unc.edu.
authors.forename: Anne E
authors.initials: AE
authors.lastname: Sanders
authors.forename: Gary D
authors.initials: GD
authors.lastname: Slade
authors.forename: Eric
authors.initials: E
authors.lastname: Bair
authors.forename: Roger B
authors.initials: RB
authors.lastname: Fillingim
authors.forename: Charles
authors.initials: C
authors.lastname: Knott
authors.forename: Ronald
authors.initials: R
authors.lastname: Dubner
authors.forename: Joel D
authors.initials: JD
authors.lastname: Greenspan
authors.forename: William
authors.initials: W
authors.lastname: Maixner
authors.forename: Richard
authors.initials: R
authors.lastname: Ohrbach
mesh_terms: D000328:Adult; D017668:Age of Onset; D005157:Facial Pain / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006304:Health Status; D006801:Humans; D015994:Incidence; D008297:Male; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013705:Temporomandibular Joint Disorders / Q000453:epidemiology* / Q000209:etiology
keywords: Temporomandibular disorder; comorbidity; epidemiology; prospective cohort studies