Case-control study to investigate the relevance of C-reactive protein in patients with depression
2021
King’s College London, London, United Kingdom
This case-control study used C-reactive protein (CRP), genetic and phenotypic data from the UK Biobank to investigate the pathways leading to inflammation in depressive disorders.
Data were used from 26,894 participants with a lifetime diagnosis of major depressive disorder from the Composite International Diagnostic Interview and 59,001 controls who reported having no mental disorder and not taking antidepressant medication. Linear regression models were constructed for log CRP level to adjust for the effects of age, sex, body mass index (BMI) and smoking, and to examine whether the polygenic risk score (PRS) for major depression was associated with log CRP level, and whether the association between log CRP level and major depression remained after adjustment for early childhood trauma, socioeconomic status and self-reported health status.
CRP levels were significantly higher in patients with depression than in control subjects, and more patients than control subjects had CRP levels above 3 mg/L, indicating low-grade inflammation. The PRS for depression was positively and significantly associated with log CRP levels, but this association was no longer significant after adjustment for BMI and smoking. The association between depression and elevated log CRP levels was substantially reduced after adjustment for the above clinical and sociodemographic factors, but still remained significant.
The data suggest that the "genetic" contribution to increased inflammation in depression is due to the regulation of eating and smoking habits rather than an "autoimmune" genetic predisposition. Furthermore, the association between depression and increased inflammation, even after full adjustment, suggests either the presence of as yet unknown or unmeasured psychosocial and clinical confounders or that a core biological link between depression and increased inflammation exists independent of confounders.
Elevated C-reactive protein in patients with depression, independent of genetic, health, and psychosocial factors: results from the UK Biobank
Carmine M. Pariante
Added on: 03-27-2024
[1] https://ajp.psychiatryonline.org/doi/10.1176/appi.ajp.2020.20060947
