Association of − 717 A > G (rs2794521) CRP polymorphism with high cardiovascular risk by C-reactive protein in systemic lupus erythematosus patients

Introduction Systemic lupus erythematosus (SLE) is an autoimmune disease where genetic factors have been related to SLE susceptibility and disease severity. CRP polymorphisms have been associated with high C-reactive protein (CRP) serum levels, cardiovascular disease (CVD), and high clinical disease activity in SLE patients; however, the evidence is still inconclusive. Objective This study was aimed to assess the association of the − 717 A > G, − 409 G > A, + 1444 C > T, and + 1846 C > T CRP polymorphisms with genetic susceptibility, clinical disease activity, and CVD risk in Mexican-mestizo SLE patients. Methods A comparative cross-sectional study was conducted on 369 unrelated women: 183 with SLE according to the 1997 SLE-ACR criteria and 186 healthy subjects (HS). The clinical disease activity was assessed by the Mex-SLEDAI score; CRP and lipid profile were quantified by turbidimetry and colorimetric-enzymatic assays, respectively. The CRP polymorphisms genotyping was carried out by allelic discrimination. Results SLE patients with − 717 AA genotype had higher CRP serum levels than SLE carriers of AG and GG genotypes (AA = 5 mg/L vs. AG = 3.2 mg/L vs. GG = 2.4 mg/L; p = 0.01), and the AA genotype was associated with high CVD risk by CRP in SLE patients (OR = 3; CI: 1.2–7.6; p < 0.01). Conclusions The − 717 A > G CRP polymorphism is a risk factor for high CRP levels and high CVD risk in Mexican-mestizo SLE patients. Key Points • Cardiovascular disease is one of the major causes of death in SLE patients due to the higher prevalence of traditional and non-traditional cardiovascular risk factors. • C-reactive protein is a liver-derived acute-phase protein suggested as one powerful independent risk predictor factor for cardiovascular disease. • Single nucleotide polymorphisms in CRP have been suggested as genetic susceptibility factors that could modify the SLE pathophysiology outcomes. • Mexican-mestizo SLE patients carrying the −717 A>G CRP AA genotype had 3-fold high cardiovascular disease risk than SLE patients with AG or GG genotypes