PHOENIX – African Americans with systemic lupus erythematosus are more likely to experience recurrent hospitalizations for cardiovascular disease, compared with other racial/ethnic groups, results from a single-state registry study found.
“SLE is an autoimmune disease that causes inflammation affecting multiple organ systems including the cardiovascular system,” Meghan Angley, MPH, said at the Epidemiology and Prevention/Lifestyle and Cardiometabolic Health meeting. “Therefore, individuals with SLE are at risk for early CVD. African Americans represent the racial group at greatest risk for SLE.”
According to Ms. Angley, with the department of epidemiology at Emory University, Atlanta, white women with SLE have CVD associated mortality 12 years earlier than their non-SLE counterparts, while African American women with SLE have CVD-associated mortality 19 years earlier than their non-SLE counterparts. “We know that recurrent hospitalizations for CVD are associated with mortality,” she said. “These represent potential points of identification of high-risk individuals and also points of interventions.”
In order to study racial disparities across recurrent hospitalizations for cardiovascular disease in an SLE population, Ms. Angley and her colleagues drew from the Georgia Lupus Registry, which is a population-based registry of patients with validated SLE in two Georgia counties. They included all cases diagnosed between 2000 and 2004. The registry was linked to records of all inpatient hospitalizations in Georgia between 2000 and 2013. The researchers used ICD-9 codes to identify hospitalizations for coronary heart disease, peripheral artery disease, cerebrovascular disease, and heart failure and used the Prentice-Williams-Peterson model for recurrent time-to-event analysis. Specifically, they looked at the total time scale from the point of diagnosis to each of the subsequent CVD hospitalizations and truncated the number of hospitalizations at three to maintain stable modeling estimates. The analysis was censored at the time of patient death or at the end of 2013 and adjusted for sex and age at diagnosis.
The sample included 417 African Americans with SLE and 149 non–African Americans with the disease. Most (86%) were female, and the non–African American group was slightly more likely to have been diagnosed with SLE after the age of 45 years, compared with the African American group (36% vs. 30%, respectively).
Ms. Angley and her colleagues found that 24% of African Americans had at least one CVD hospitalization, and 14% had at least two, while 13% of non–African Americans had at least one CVD hospitalization, and 5% had at least two. Among those in the African American group, reasons for hospitalizations were congestive heart failure, (58%), cerebrovascular disease (27%), coronary heart disease (18%), and peripheral artery disease (2%). Among those in the non–African American group, reasons for hospitalizations were congestive heart failure (38%), coronary heart disease (38%), cerebrovascular disease (25%), and peripheral artery disease (6%).
Overall, African American race was associated with recurrent hospitalizations (adjusted hazard ratio, 1.9). In an event-specific stratified analysis, the association between African American race and the hazard of recurrence became even more pronounced with each event (hospitalization 1 aHR, 1.2; hospitalization 2 aHR, 1.5; hospitalization 3 aHR, 1.9). The researchers also observed that African Americans were hospitalized sooner, compared with non–African Americans: a median of 3.68 versus 4.61 years for hospitalization 1, 3.73 years versus 5.98 years for hospitalization 2, and 4.84 years versus 8.14 years for hospitalization 3.
“African Americans with SLE are more likely to experience recurrent hospitalizations for CVD,” Ms. Angley concluded at the meeting, which was sponsored by the American Heart Association. “The events occur sooner after diagnosis than in non–African Americans, suggesting that African Americans may be more vulnerable to the cardiovascular complications of SLE. Our next steps include examining potential reasons for these disparities, such as looking at primary care patterns over time, SLE severity over time, and treatment at CVD hospitalizations.”
In an interview, one of the meeting session’s moderators, Sherry-Ann Brown, MD, called for additional research to determine the reasons for disparities that were observed between African Americans with SLE and their non–African American counterparts. “We need to figure out why and address it,” said Dr. Brown, who is a cardiologist and physician-scientist at Mayo Clinic, Rochester, Minn. “We recognize that social determinants of health, such as insurance, socioeconomic factors, and psychosocial factors, can contribute. We need to figure out the additional steps we need to take in order to close that gap.”
Ms. Angley reported having no disclosures. The study was funded by grants from the Centers for Disease Control and Prevention and by the National Institutes of Health.
SOURCE: Angley M et al. Epi/Lifestyle 2020, Abstract 5.