Disease duration of greater than 10 years is associated with a significantly increased risk for cardiovascular morbidity and mortality in patients with mild systemic lupus erythematosus (SLE) compared with control participants with similar cardiovascular risk factors, according to study results published in Lupus Science & Medicine.
Previous studies have shown that SLE is associated with an increased risk for premature cardiovascular morbidity and all-cause mortality. The objective of the current study was to identify prognostic factors in patients with SLE vs control participants.
The study included patients with SLE aged less than 70 years from the outpatient clinic at the Karolinska University Hospital, Sweden, and age- and sex- matched control participants from the general population without a history of cardiovascular disease who underwent carotid ultrasound.
The outcome of the study was the composite event of incident cardiovascular event (acute myocardial infarction, hospitalization for angina pectoris, coronary artery bypass grafting or percutaneous coronary intervention, ischemic stroke, and transient ischemic attack) or death from all causes.
The study sample included 99 patients with mild SLE (mean age, 47 years; 87% women; mean disease duration, 12 years) and 109 control participants (mean age, 49 years; 91% women). Lupus disease activity was assessed using the Systemic Lupus Erythematosus Diseases Activity Index (SLEDAI), and organ damage was measured using the Systemic Lupus International Collaborating Clinics (SLICC) Damage Index.
There was no difference in baseline carotid intima-media thickness between patients with lupus and control participants, but carotid plaques were more common among those with lupus (38.5% vs 26.6%, P =.068).
During a median follow-up of 10.1 years, 12 patients with SLE and 4 control participants reached the outcome of cardiovascular event or mortality (P =.022). After adjustment for age, sex, and smoking habits, the risk for adverse outcomes was 3.7-fold higher in patients with SLE compared with the control participants (hazard ratio [HR], 3.7; 95% CI, 1.2-11.5; P =.025).
Event-free survival was significantly shorter in patients with SLE who were older, those with higher levels of triglycerides and waist circumference, diabetes mellitus, and higher carotid intima-media thickness, SLICC, and SLE-antiphospholipid syndrome (SLE-APS). After controlling for age and sex, adverse outcomes were significantly associated with both SLICC score (HR, 1.66; 95% CI, 1.20-2.28; P =.002) and SLE-APS syndrome (HR, 9.08; 95% CI, 2.71-3.05; P <.001).
Compared with each measure separately, a combination of carotid intima-media thickness and SLICC significantly improved the predictive ability (P <.001). The combination of carotid intima-media thickness and SLE-APS also improved the predictive ability of the model (P <.001).
Researchers acknowledged several study limitations, including the relatively small sample size and missing follow-up data in the control group, no data on plaque burden, and the potential competing risk for death.
“This study provides data to support the need for a comprehensive approach to risk management in SLE, including assessment of both traditional risk factors, disease-specific characteristics and subclinical atherosclerosis,” the researchers concluded.
Ajeganova S, Hafström I, Frostegård J. Patients with SLE have higher risk of cardiovascular events and mortality in comparison with controls with the same levels of traditional risk factors and intima-media measures, which is related to accumulated disease damage and antiphospholipid syndrome: a case-control study over 10 years. Lupus Sci Med. 2021;8(1):e000454. doi:10.1136/lupus-2020-000454