Correlation of brain-derived neurotrophic factor and inflammatory markers in rheumatoid arthritis patients with depressive symptoms / 中华风湿病学杂志

ABSTRACT

Objective:To evaluate the correlation between brain-derived neurotrophic factor (BDNF) and inflammatory markers in rheumatoid arthritis (RA) patients with depressive symptoms.Methods:This study was a cross-sectional study. RA patients' medical history were recorded and disease activity was evaluated. Serum BDNF, interleukin (IL)-6, tumor necrosis factor (TNF)-α were tested and clinical inflammatory indicators such as C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen (FIB), serum amyloid A (SAA) were recorded. RA patients were instructed to fill in the patient health Questionnaire-9 (PHQ-9) scale by themselves. Patients with a score greater than or equal to 5 were included in the RA with depressive symptoms group, and patients with a score of 4 or less were included in the RA without depressive symptoms group. The changes in BDNF and inflammatory indexes were compared between the two groups. Correlation analysis of PHQ-9, BDNF, inflammatory markers and DAS28 was performed. Logistic regression analysis was performed to find the risk factors of depression in RA.Results:A total of 140 RA patients were enrolled in this study, and 66 patients (47.1%) with a PHQ-9 score greater than or equal to 5 were included in the RA with depressive symptoms group. Compared with the RA without depressive symptoms group, RA patients with high disease activity, single and living alone, poor economic self-awareness and unemployed were more likely to have depressive symptoms. The serum level of BDNF[(2 276±333) pg/ml vs (1 367±431) pg/ml, t=13.91, P<0.001], IL-6[(39±28) pg/ml vs (27±8) pg/ml, t=3.66, P<0.001], TNF-α[(9.0±7.2) pg/ml vs (6.6±3.9)pg/ml, t=2.43, P=0.035], CRP[(25±13) mg/L vs (17±11) mg/L, t=3.94, P<0.001], ESR[(48±18) mm/1 h vs (34±21) mm/1 h, t=4.14, P=0.024], Fib[(3.8±1.1) g/L vs (3.0±0.5) g/L, t=5.92, P=0.023], SAA[(64±39) mg/L vs (37±19) mg/L, t=5.32, P<0.001] in RA with depressive symptoms group were significantly higher than those in RA without depressive symptoms group. Serum BDNF was significantly positively correlated with PHQ-9 score ( r=0.66, P<0.001), IL-6( r=0.20, P=0.019), TNF-α ( r=0.14, P=0.090), CRP ( r=0.32, P<0.001), ESR ( r=0.20, P= 0.001), Fib ( r=0.28, P=0.001), SAA( r=0.28, P=0.001) and DAS28 ( r=0.37, P<0.001) . BDNF [ OR (95% CI) =1.578(1.257, 2.354), P=0.001], IL-6[ OR (95% CI) =1.073(1.012, 1.075), P=0.006], CRP[ OR(95% CI)=1.085(1.045, 1.178), P=0.001], SAA[ OR(95% CI)=1.125(1.004, 1.198), P=0.018] and unemployment were risk factors for depressive symptoms in RA. Conclusion:Serum BDNF is positively correlated with PHQ-9 scores, inflammatory markers and disease activity in RA patients. BDNF, IL-6, CRP, SAA and unemployment are risk factors for depressive symptoms in RA. Effective treatment of RA can reduce the occurrence of depression symptoms.