Black patients with lupus have higher risk of stroke and ischemic heart disease

New research reveals that, in the U.S., Black patients with lupus have a threefold higher risk of stroke and a 24-fold higher risk of ischemic heart disease. The study also found several lupus-specific symptoms that predict stroke and IHD in these patients. Details of the study was presented at ACR Convergence, the American College Rheumatology's annual meeting (ABSTRACT #0433).

Systemic lupus erythematosus, also called lupus or SLE, is a chronic disease that causes systemic inflammation affecting multiple organs, such as the skin, joints, kidneys, the tissue lining the lungs (pleura), heart (pericardium) and brain. Many patients experience fatigue, weight loss and fever. The disease is more common among Black, Asian, and Native American people and tends to be worse in these groups.

Black people with lupus have a 19-fold higher occurrence of cardiovascular disease compared to other groups and have a disproportionately higher number of stroke-related events around the time of lupus diagnosis. Researchers wanted to know more about the specific risks and predictors of stroke and ischemic heart disease in Black people with lupus.

"The risk for developing cardiovascular disease is up to 52 times higher in patients with lupus, compared to patients without lupus. Black populations have three times higher risk to develop lupus, develop it at a significantly younger age and have more severe disease. However, most prior lupus and cardiovascular disease (CVD) studies were conducted in predominantly white cohorts, limiting the generalizability of the findings," says the study's co-author, Shivani Garg, MD, MS, Assistant Professor of Medicine at the University of Wisconsin School of Medicine and Public Health. "It's important to quantify the risk, predictors and timing of stroke and ischemic heart disease in Black people with lupus in order to guide early CVD diagnosis and preventive interventions in this at-risk population." The study highlights the need for aggressive heart disease preventive care to reduce these racial disparities and improve lupus outcomes, particularly in recently diagnosed patients, she adds.

The researchers collected data from the Georgia Lupus Registry of lupus patients from Atlanta. They identified patients from 2002 to 2004 who met four or more of the ACR's SLE criteria or three criteria with a final lupus diagnosis by their own rheumatologist. They matched the patients to the Georgia Hospital Discharge Database and National Death Index from 2000 to 2013.

Stroke and ischemic heart disease-related hospitalizations and deaths were based on hospital admission and death medical codes. Transient ischemic attacks were included in the stroke data, and myocardial infarction (heart attack) and angina were included in ischemic heart disease data. The researchers also examined symptoms that predicted strokes and ischemic heart disease. Of the 336 lupus patients included in the final study, 87% were female, 75% were Black, and the mean age at diagnosis was 40.

They found 38 stroke-related and 25 ischemic heart disease -related health events or deaths that occurred from two years before to 14 years after a lupus diagnosis. In the 11% of patients who had strokes, the mean age at first stroke was 48, and 78% of the strokes occurred in females. Ninety percent of the strokes occurred in Black patients. The peak number of strokes happened in the second year after lupus diagnosis. The study also showed that 8% of the patients had ischemic heart disease, and their mean age at diagnosis was 52. All the ischemic heart disease cases occurred in females, 96% occurred in Black patients and the peak number of cases occurred in the 14th year after diagnosis with lupus. All in all, the data showed that Black patients with lupus have a threefold higher stroke risk and a 24-fold higher ischemic heart disease risk than other groups.

What about potential predictors of stroke or ischemic heart disease? Discoid rash at the time of lupus diagnosis predicted a five-fold higher risk of stroke, while renal disorder at the time of lupus diagnosis predicted a two-fold higher stroke risk. Neither discoid rash nor renal disorder predicted ischemic heart disease, however. Strong predictors of ischemic heart disease were neurologic disorders (prior psychosis or seizure) and immunologic disorders (anti-DNA, anti-Sm, or antiphospholipid antibodies), but these did not predict strokes.

These findings highlight significant racial disparities in both stroke and ischemic heart disease among patients with lupus, says Dr. Garg.

Our study increases awareness of higher risk, the timing of accelerated risk and disease presentations that contribute to higher risk of stroke and ischemic heart disease among Black patients with lupus. Such knowledge can help patients and providers look for and diagnose CVD events earlier and discuss starting preventive care to reduce their risk. Timely interventions could help reduce cardiovascular disparities in lupus and reduce CVD-related morbidity and mortality in young lupus patients, who are at relatively higher risk of premature CVD."

Dr. Shivani Garg, MD, MS, Assistant Professor of Medicine, University of Wisconsin School of Medicine and Public Health