Title Page

Abstract

Contents

Chapter 1. Introduction 8

1.1. Study background 8

1.2. Purpose of research 10

Chapter 2. Methods 11

2.1. Study design, setting, and participants 11

2.2. Assessment of depression 12

2.3. Assessments of plasma biomarkers 12

2.4. Assessment of covariates 13

2.5. Statistical analyses 14

Chapter 3. Results 17

3.1. Descriptive statistics 17

3.2. Cross-sectional association between depression and plasma levels of monocyte trafficking-related molecules 17

3.3. Association between plasma levels of monocyte trafficking-related molecules and the course of depression 19

3.4. Association between plasma levels of monocyte trafficking-related molecules and risk of incident depression 20

Chapter 4. Discussion 22

4.1. Cross-sectional association between depression and plasma levels of monocyte trafficking-related molecules 22

4.2. Association between plasma levels of monocyte trafficking-related molecules and the risk of incident/recurrent depression 24

4.3. Comprehensive discussion and conclusion 27

Bibliography 43

초록 50

Table 1. Comparison of characteristics between included and excluded participants 33

Table 2. Operational criteria for subsyndromal depression 34

Table 3. Cut-off values for the plasma levels of monocyte trafficking-related molecules 35

Table 4. Baseline characteristics of all participants by the presence of depression 36

Table 5. Association of the depression and other covariates with the plasma levels of monocyte trafficking-related molecules 37

Table 6. Multinomial logistic regression analysis for the association between the plasma levels of monocyte trafficking-related molecules and the course of depression 38

Table 7. Binomial logistic regression analysis for the association between the plasma levels of monocyte trafficking-related molecules and the risk of... 39

Table 8. Baseline characteristics of euthymic participants by the levels of plasma monocyte chemoattractant protein-1 (MCP-1) 40

Table 9. Baseline characteristics of euthymic participants by the levels of plasma vascular cell adhesion molecule-1 (VCAM-1) 41

Table 10. Cox proportional hazard analysis for the association between the plasma levels of monocyte trafficking-related molecules and the risk of... 42

Figure 1. Distribution of the plasma levels of monocyte trafficking-related molecules 31

Figure 2. Correlations between the plasma levels of monocyte trafficking-related molecules 32