Lupus anticoagulant (LAC) may serve as a potential biomarker of cardiac dysfunction in patients with systemic lupus erythematosus (SLE), according to study findings published in the Journal of Autoimmunity.
SLE is a chronic autoimmune disorder characterized by circulating autoantibodies causing inflammation and tissue damage, which increases risk for cardiac dysfunction. Patients with SLE present with pericarditis, myocarditis, arrhythmias, heart failure, myocardial infarction, valvular disease, and stroke.
Researchers in Denmark conducted a 5-year follow-up study to identify characteristics associated with cardiac size and function in patients with SLE who received care at the Copenhagen Lupus and Vasculitis Clinic at Copenhagen University Hospital between June 2013 and May 2014.
Patients provided blood samples and updated echocardiograms and the researchers compared 5-year measurements against baseline data to identify potential biomarkers for cardiovascular dysfunction in the patient population. Blood biomarker analysis included creatinine, total cholesterol, triglycerides, low-density lipoprotein (LDL), high-density lipoprotein (HDL), LAC, immunoglobulin M (IgM) and G (IgG) antiphospholipid antibodies (aPL), IgG anticardiolipin antibodies (aCL), and anti-beta-2 glycoprotein I antibodies (aB2GPI).
A total of 108 patients with SLE (90% women; mean age, 46±13 years) were included in the analysis. Deteriorating diastolic function was observed during baseline vs 5-year echocardiographic measurements of tricuspid regurgitation peak velocity (2.0±0.6 vs 2.2±0.4 mmHg; P <.001) and peak velocities during early (E) and late (A) diastole denoted by the E/A ratio (1.4±0.5 vs 1.3 ± 0.5; P =.002). Left ventricular end-diastolic volume index was increased (43.7±13.9 vs 52.5±15.7 mL/m2; P <.001); however, the researchers did not observe changes in left or right ventricular systolic function.
After 5 years, LAC significantly correlated with decreased diastolic function, such as lower E/A ratio (P =.04), increased left ventricular atrial volume (P =.01), and left ventricular dilation (P =.01).
Study limitations included lack of a control group and relatively small sample size, which prohibited stratified analyses having sufficient power to assess other correlations. The researchers did not analyze other inflammatory biomarkers, the effect of specific medications, valvular heart disease, and cumulative damage.
“LAC is known to have implications for the microvascular circulation, but the clinical significance of the present findings is yet to be elucidated,” the study authors said.
Myhr KA, Zinglersen AH, Hermansen MLF, et al. Left ventricular size and function in patients with systemic lupus erythematosus associate with lupus anticoagulant: an echocardiographic follow-up study. J Autoimmun. 2022;132:102884. doi:10.1016/j.jaut.2022.102884