Low Serum Bilirubin Levels in Women With the Antiphospholipid Syndrome

Abstract

The aim: To investigate the relationship between serum bilirubin level and the presence of the APS in women with a history of spontaneous miscarriages. Materials and methods: Fifty six women aged 22-38 (median 27) years with a history of spontaneous miscarriages were divided into two groups: 33 women with the APS and 23 without. Patients were tested for the presence of lupus anticoagulant, anticardiolipin, anti-β2-glycoprotein 1, antiphospholipid antibodies and genetic thrombophilic defects. Results: Groups were comparable by age, blood pressure, BMI, co-morbidity (anemia, heart abnormality, thyroid disease, overweight). Median serum total bilirubin levels were 7,2 μmol/L (interquartile range [5,8-9,7]) in women with the APS and 10,5 μmol/L (interquartile range [7,5-15,1]) in control group, p=0.005. The chance of detecting a total bilirubin level of less than 8 μmol/L is 4.1 times higher in the APS patients than in the control group (OR 4,1; 95% CI 1,274-13,213). Logistic regression analysis found a statistically significant association between total bilirubin and the presence of the APS (odds ratio, 0.856; 95% CI, 0.734-0.997, p =0.046). Patients with the APS had elevated serum C-reactive protein (medians 2,3 vs 1,1 mg/L, p=0.01) and fibrinogen (medians 2,8 vs 2,5 g/L, p=0.006) levels compared with controls. Correlation analysis revealed a significant correlation between all types of bilirubin and inflammatory markers. Conclusions: All types of serum bilirubin (total, direct and indirect) are significantly reduced in women with APS, associated with higher inflammatory markers and lower levels of 25-hydroxyvitamin D, which may be the result of oxidative stress.

Relationship between bilirubin and systemic lupus erythematosus: A systematic review and meta‐analysis

“…The available literature suggests that there is an elevation of oxidative stress in SLE, which leads to dysregulation of immune system, abnormal activation and processing of signals related to cell‐death, and production of autoantibodies 3 . According to numberous reports, bilirubin is commonly recognized as an antioxidant and immunomodulator, potentially serving as a safeguard aganist autoimmune disease 4 . It seems related to the disease activity of rheumatoid arthritis, Takayasu arteritis, Crohn's disease, and primary Sjögren's Syndrome 5–7 .…”

“…3 According to numberous reports, bilirubin is commonly recognized as an antioxidant and immunomodulator, potentially serving as a safeguard aganist autoimmune disease. 4 It seems related to the disease activity of rheumatoid arthritis, Takayasu arteritis, Crohn's disease, and primary Sjögren's Syndrome. [5][6][7] Besides, many studies have indicated a strong correlation between SLE and serum bilirubin.…”