The associations among vitamin D deficiency, C-reactive protein, and depressive symptoms

• Published in: Journal of psychosomatic research Vol. 90; pp. 98 - 104
• Main Authors: Shin, Young-Chul, Jung, Chan-Hyun, Kim, Hyung-Jun, Kim, Eun-Jin, Lim, Se-Won
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01.11.2016
• Subjects: Adult; Aged; Biomarkers - blood; C-reactive protein; C-Reactive Protein - metabolism; Cross-Sectional Studies; Depression - blood; Depression - diagnosis; Depression - psychology; Depressive symptom; Female; Humans; Male; Middle Aged; Psychiatry; Republic of Korea - epidemiology; Vitamin D; Vitamin D - blood; Vitamin D Deficiency - blood; Vitamin D Deficiency - diagnosis; Vitamin D Deficiency - psychology; Young Adult; Vitamin D; Depressive symptom; C-reactive protein
• ISSN: 0022-3999; 1879-1360; 1879-1360
• DOI: 10.1016/j.jpsychores.2016.10.001

Vitamin D deficiency has been reported to be associated with depression, but the underlying mechanisms aren't well understood. Our study aims to investigate the associations among serum vitamin D, C-reactive protein (CRP) level, and depressive symptoms. Serum levels of Vitamin D and CRP were measured from 52,228 participants. Depressive symptoms were assessed using a Korean version of the CES-D scale. We used logistic regression to calculate the odds ratio (ORs) of depressive symptoms according to vitamin D and CRP levels. The regressions were adjusted for covariates, and each model was adjusted mutually for vitamin D and CRP levels. A significant difference was found in vitamin D status between depressed and non-depressed participants, but CRP status was not significantly different. The OR for the presence of depressive symptoms was significantly increased in participants with vitamin D deficiency after adjusting for potentially confounding factors (Adjusted OR=1.158, 95% CI=1.003–1.336, p=0.046). The OR of depressive symptoms was not significantly increased in individuals with high (3.01-10mg/L) CRP level compared to individuals with low (≤3mg/L) CRP level (Adjusted OR=1.004, 95% CI=0.821–1.227, p=0.97). There was no significant association between vitamin D and CRP level. Additional adjustment for serum CRP level did not weaken the resulting association between vitamin D deficiency and the presence of depressive symptoms. Vitamin D deficiency was associated with depressive symptoms, but elevated serum CRP level was not. The results indicate that CRP level does not account for the association between vitamin D deficiency and the presence of depressive symptoms. •Serum levels of Vitamin D and CRP were measured from 52,228 participants who attended employee health screenings.•Depression was assessed using a Korean version of the CES-D scale.•Vitamin D deficiency was associated with depressive symptoms, but elevated serum CRP level was not.•The serum CRP and vitamin D levels did not account for each other’s association with depression.