The Association between Temporomandibular Disorder and Sleep Apnea-A Nationwide Population-Based Cohort Study

Abstract

An increased incidence of temporomandibular disorders (TMD) among patients with sleep apnea (SA) has been reported. However, the association between TMD and SA has not been demonstrated in a large-scale study. This population-based cohort study with the Taiwan National Health Insurance (NHI) Research Database aimed to understand the association between SA and TMD. We identified adult patients with suspected SA (identified with diagnostic codes) and excluded those diagnosed with TMD prior to SA. Patients with SA diagnosis after polysomnography were also identified as probable SA patients. The index dates were the dates of their initial SA diagnosis. Ten control subjects were matched, by age and sex, to each SA patient, and were assigned the same index dates as the SA patients. In total, 10,408 suspected SA patients (including 4105 probable SA patients) matched to 104,080 control subjects (including 41,050 subjects matched to the probable SA patients) in this study. The TMD incidence rate was significantly higher in the SA patients than in the control subjects (2.8 vs. 1.0 per thousand-patient-year in probable SA patients vs. the corresponding control subjects, with an adjusted incidence rate ratio [95% confidence interval] = 2.5 [2.3-2.7], p < 0.0001). SA patients significantly showed a higher cumulative incidence of TMD than the corresponding control subjects (p < 0.0001). Multivariable Cox regression analysis revealed SA as an independent risk factor for the development of TMD (adjusted hazard ratio = 2.5 [1.7-3.7], p < 0.0001). In summary, this study confirmed an increased TMD incidence in the SA patients. While treating TMD patients, dentists should pay careful attention to the potential underlying SA.

Keywords: sleep apnea; sleep disordered breathing; temporomandibular disorder.

Figure A1

The cumulative incidences of temporomandibular disorder in female subjects (a,b), male subjects (c,d), subjects ≤ 50 years of age (e,f), and subjects > 50 years of age (g,h). The analyses were taken in study arm A (suspected SA vs. control A) (a,c,e,g) and study arm B (probable SA vs. control B) (b,d,f,h). The red continuous lines and blue dashed lines show the cumulative incidence of temporomandibular disorder for the sleep apnea (SA) patients and the control subjects, respectively.

Figure 1

Algorithm to identify the study population. Abbreviations: LHID2005 = Longitudinal Health Insurance Database 2005; SA = sleep apnea; TMD = temporomandibular disorder; PSG = polysomnography; y/o = years old.

Figure 2

The cumulative incidences of temporomandibular disorder. The red continuous lines show the cumulative incidence of temporomandibular disorder for the sleep apnea patients; the blue dashed lines show the cumulative incidence of temporomandibular disorder for the control subjects. (a) Study arm A (the suspected sleep apnea cohort vs. control A cohort); (b) Study arm B (the probable sleep apnea cohort vs. control B cohort).

Figure 3

Stratified analyses of multivariable Cox analyses. (a) Study arm A (suspected SA vs. control A); (b) Study arm B (probable SA vs. control B). Adjusted hazard ratios (95% confidence intervals) of sleep apnea, adjusted for sex, age, residency, income level, and the presence of various comorbidities (except for the stratifying variable) are presented. ^† Hazard ratio cannot be estimated because of small sample size. Abbreviations: SA = sleep apnea; CCI = Charlson Comorbidity Index.