Black Patients with Lupus Face Significantly Greater Cardiovascular Risks

Shivani Garg, MD, MS (UW)

Stroke and ischemic heart disease are significantly more likely among black patients with systemic lupus erythematosus (SLE) than white comparators, according to an assessment of a statewide lupus registry which highlights significant outcome disparity in the common rheumatic condition.

In a new study presented at the American College of Rheumatology (ACR) Convergence 2020 this week, a team of US investigators reported findings from the Georgia Lupus Registry showing that black patients with lupus face a 24-fold increased risk of ischemic heart disease, with a series of multisystem biomarkers indicative of such risks.

Led by Shivani Garg, MD, MS, Assistant Professor of Medicine at the University of Wisconsin School of Medicine and Public Health, the team sought to measure risk and predictors of both stroke and heart disease among the registry’s database of predominately black, population-based cohort.

They conducted their review with a bevy of foundational evidence showing cardiovascular disease risk is up to 52 times more common in patients with lupus, and that black populations face a three-fold greater risk of lupus development, particularly at younger ages and with more severe disease progression.

“However, most prior lupus and cardiovascular disease (CVD) studies were conducted in predominantly white cohorts, limiting the generalizability of the findings,” Garg said in a statement. “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.”

In assessing the Atlanta-based Georgia Lupus Registry, Garg and colleagues observed incident patients from 2002-2004 who met ≥4 ACR SLE criteria, or 3 criteria, with a final diagnosis of SLE delivered by a board-certified rheumatologist. They matched patients to the Georgia Hospital Discharge Database and National Death Index from 2000-2013.

Investigators classified stroke- and ischemic heart disease-related hospitalizations and deaths by the first 3 admission or cause-of-death codes. Predictors for either event were examined through the Cox proportional hazards models.

Stroke- and IHD-related hospitalizations and deaths were classified by the first three admission or cause of death codes. Stroke also included transient ischemic attack, and IHD included myocardial infarction and angina. Predictors of strokes and IHD were examined using Cox proportional hazards models.

In the 336 observed incident lupus patients, 87% were female, and 75% were black with a mean age of 40 years old at SLE diagnosis. Investigators observed 38 stroke-related and 25 ischemic heart disease-related events or deaths from the period 2 years before through 14 years post-diagnosis.

Though strokes were prevalent in just 11% of SLE patients, 90% occurred in black patients. Ischemic heart disease was associated with even greater disparity: 8% of all patients, with 96% occurring in black patients.

Garg and colleagues reported a three-fold greater risk for stroke (HR, 3.4; 95% CI, 1.2-10; P <.03), and a 24-fold greater risk for ischemic heart disease (HR, 24; 95% CI, 3-206; P <.004) among black patients with lupus versus white patients.

Highly common stroke risk indicators included discoid rash at the time of SLE diagnosis, as well as renal disorder. Ischemic heart disease risk indicators included neurologic and immunologic disorders.

Investigators concluded their findings provide a unique perspective into significantly different predictors of SLE-associated cardiovascular disease, and a greater understanding of racial disparities in this patient population.

“Such knowledge can help patients and providers look for and diagnose CVD events earlier and discuss starting preventive care to reduce their risk,” Garg said. “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.”

The study, “Racial Disparities and New SLE-Specific Predictors of Stroke and Ischemic Heart Disease in Patients with Lupus,” was presented at ACR 2020.