Dataset Information

Causal association between body mass index and temporomandibular disorders: a bidirectional two-sample Mendelian randomization analysis.

ABSTRACT:

Background

Observational studies have shown that body mass index (BMI) is highly correlated with the occurrence of temporomandibular disorders (TMDs). However, these studies failed to present a causal relationship. Thus, we aimed to performed a Mendelian randomization (MR) study to investigate causality between BMI and TMDs.

Methods

We performed a two-sample bidirectional MR analysis using large-scale genome-wide association studies (GWAS). Data were obtained from a large-scale BMI dataset (N = 322,154), TMDs dataset (N = 134,280). The causal effects were estimated with inverse-variance weighted (IVW) method, MR Egger, weighted median. Sensitivity analyses were implemented with Cochran's Q test, MR-Egger intercept test, MR-PRESSO, leave-one-out analysis and the funnel plot.

Results

In the forward MR analysis, a genetic prediction of low BMI was causally associated with a higher risk of TMDs (IVW OR: 0.575, 95% CI: 0.415-0.798, p: 0.001). Similar results were obtained using other complementary methods (MR Egger OR: 0.270, 95% CI: 0.104-0.698, p: 0.009; weighted median OR: 0.496, 95% CI: 0.298-0.826, p: 0.007). In the reverse MR results, TMDs was shown to have no significant effect on BMI (all p > 0.05). No pleiotropy and heterogeneity were detected in the bidirectional analysis (p > 0.05).

Conclusion

A lower BMI might be causally associated with increased risk of TMDs, supporting the importance of weight control for the prevention of TMDs. Clinicians should pay more attention to the low-BMI patients among those seeking medical advice due to temporomandibular joint discomfort.

SUBMITTER: Chen X

PROVIDER: S-EPMC10355070 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Publications

Causal association between body mass index and temporomandibular disorders: a bidirectional two-sample Mendelian randomization analysis.

Chen Xin X Cheng Zheng Z Xu Junyu J Zhao Zhibai Z Jiang Qianglin Q

BMC oral health 20230718 1

<h4>Background</h4>Observational studies have shown that body mass index (BMI) is highly correlated with the occurrence of temporomandibular disorders (TMDs). However, these studies failed to present a causal relationship. Thus, we aimed to performed a Mendelian randomization (MR) study to investigate causality between BMI and TMDs.<h4>Methods</h4>We performed a two-sample bidirectional MR analysis using large-scale genome-wide association studies (GWAS). Data were obtained from a large-scale BM ...[more]

PMID: 37464321

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Dataset Information

Causal association between body mass index and temporomandibular disorders: a bidirectional two-sample Mendelian randomization analysis.

Background

Methods

Results

Conclusion

Publications

Causal association between body mass index and temporomandibular disorders: a bidirectional two-sample Mendelian randomization analysis.

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