Background: The purpose of this study was to determine the bidirectional association between burning mouth syndrome (BMS) and depression disorders. Methods: A total of 854 pairs of BMS and 58 999 pairs of depression disorders matched 1:1 for age and sex were analyzed using conditional logistic regression models, which were adjusted for potential confounding factors. Results: Bidirectional analysis found that BMS was associated with depression disorders (odds ratio=4.64, P < 0.001) and depression disorders was also significantly associated with BMS (odds ratio=2.97, P < 0.001). Conclusion: These findings indicate a significant bidirectional association between BMS and depression disorders. The odds ratios suggest that BMS is a stronger predictor for incidence of depression disorders than depression disorders predicting incidence of BMS. Given this retrospective cohort design, the mechanisms underlying the association between BMS and depression disorders are not directly analyzed. Therefore, further investigation are needed to analyze the causality between BMS and depression disorders.

Abstract
Ⅰ. INTRODUCTION
Ⅱ. MATERIALSS AND METHODS
    1. 연구 자료
    2. 연구 대상
    3. 변수의 정의
    4. 통계 분석
Ⅲ. RESULTS
    1. BMS와 우울장애의 인구학적 특성
    2. BMS 및 우울장애와 관련된 위험 요인들
    3. BMS와 우울장애의 발생률
    4. BMS와 우울장애의 양방향 연관성
Ⅳ. DISCUSSION
Ⅴ. CONCLUSION
REFERENCES

• 조혜민(서울대학교병원 의생명연구원 응급의료연구실) | Hye Min Cho (Laboratory of Emergency Medical Services, Biomedical Research Institute, Seoul National University Hospital)
• 최혜미(전북대학교 자연과학대학 통계학과) | Hye Mi Choi (Department of Statistics, Research Institute of Applied Statistics, Jeonbuk National University)
• 조남표(전북대학교 치과대학 구강병리학교실) | Nam-Pyo Cho (Department of Oral Pathology, School of Dentistry, Institute of Biodegradable Material, Institute of Oral Bioscience, Jeonbuk National University) Corresponding author