SAN FRANCISCO — The majority of vascular events that occur early in the course of systemic lupus erythematosus cannot be attributed to atherosclerosis, judging from the results of an ongoing multinational study.
The inception cohort included 1,249 patients who enrolled in the study within a year of receiving a diagnosis of SLE. During the first 8 years of follow-up, 72 patients had 97 vascular events. Among these were 24 cases of heart failure, 23 strokes, 15 cases of angina, 13 MIs, 13 transient ischemic accidents (TIAs), and 9 cases of peripheral vascular disease (PVD).
Of these 97 events, 31 were attributable to atherosclerosis, said Dr. Murray B. Urowitz, who presented the findings at the annual meeting of the American College of Rheumatology. An event was attributed to atherosclerosis if it occurred when SLE was inactive or if atherosclerotic changes were identified on imaging or pathology.
The events that could not be attributed to atherosclerosis occurred during a phase of active lupus in 50 cases; the remaining 16 vascular events had known causes such as fluid overload, pregnancy, or coagulation disorders. The 31 events attributable to atherosclerosis occurred in 22 of the lupus patients and included 12 cases of angina, 8 MIs, 5 cases of heart failure, 4 PVDs, and 2 TIAs.
The 22 patients who developed symptomatic early ath-erosclerosis during the first 2 years of follow-up were more likely to be male, be older at lupus diagnosis, have hypertension, and be obese than were the 661 cohort members who did not have symptomatic atherosclerosis, said Dr. Urowitz, a rheumatologist at Toronto Western Hospital and a participant in the Systemic Lupus International Collaborating Clinics.
The 22 participants with atherosclerosis were also more likely to have high serum cholesterol levels and/or diabetes, be smokers, and have a family history of coronary artery disease, but these were not significant.
The participants were enrolled between 2000 and 2008; 89% were women. Whites accounted for 49%; 15% were black, 16% Hispanic, 16% Asian, and 4% other. Mean age at lupus diagnosis was 34; disease duration at the end of follow-up was 5.5 years. About 70% had been on steroid therapy, 40% had taken immunosuppressants, and 63% had used antimalarials.