Autoantibody prevalence and lupus characteristics in a unique African American population

Abstract

Objective. The Gullah population of the Sea Islands of South Carolina is a unique group of African Americans who, due to geographic and cultural factors, remained isolated with minimal genetic admixture until the 1950s. Because of the unique homogeneous nature of the Gullah, we sought to define the genetic and environmental factors contributing to systemic lupus erythematosus (SLE) in this population.Methods. Using data from our ongoing cohort study of lupus in the Gullah population, which we established in 2003, disease characteristics and serologic profiles were summarized for 184 patients with SLE, 144 unaffected first-degree relatives, and 144 matched unrelated, unaffected control subjects. These findings were compared with those in 2 other large cohorts of African Americans with SLE.Results. In the Gullah cohort, we observed a high prevalence of SLE multiplex families (26.6%), malar rash (56.0%), discoid rash (34.2%), photosensitivity (60.9%), and oral/nasal ulcerations (43.5%), but a lower prevalence of hematologic and pleuropericardial disease than has been reported in other African American cohorts. Overall renal and central nervous system involvement, number of American College of Rheumatology disease criteria met, and SLE Damage Index scores were similar to those reported in other cohorts. Of interest, male and female first-degree relatives and male and female control subjects in this cohort had similar rates of antinuclear antibody positivity, whereas lupusspecific antibodies were more prevalent in the women than in the men.Conclusion. These data indicate that the severity of lupus in the Gullah population is similar to that in other African American populations, whereas skin disease and familial disease prevalence are increased in the Gullah. These findings suggest that there is an increased genetic influence on overall disease in this cohort compared with that in other African American cohorts, which confirms the unique nature of this cohort.African Americans have a 3-fold increased prevalence of systemic lupus erythematosus (SLE), develop SLE at an earlier age, and have increased SLE-related morbidity and mortality compared with Caucasians (1-5). Multiple factors, including genetic, environmental, and socioeconomic factors, likely underlie the ethnic disparity in SLE. Socioeconomic and genetic differences alone, however, cannot explain the significant increase in prevalence of SLE in the last 20 years or the gradient of SLE between West Africa, where it is a rare disease (6-9), and the United States, where it is prevalent. These latter findings suggest that environmental factors play a key role in inducing lupus and influencing disease severity.

Autoantibodies involved in neuropsychiatric manifestations associated with systemic lupus erythematosus: a systematic review

“…Taken together, data show that anti-NR2 antibodies can occur in up to 30% of patients with SLE 28 . Nevertheless, they are infrequent in the antibodiesence of detectable anti-dsDNA antibodies and their presence in the circulation is not associated with any of the 19 neuropsychiatric syndromes associated with SLE .…”

Self-Reported Versus Objectively Assessed Exercise Adherence

“…Recruitment was facilitated through the longitudinal observational SLE Clinic Database and SLE in Gullah Health Database (Kamen et al, 2008) and conducted by a research coordinator. To be eligible for participation in the study, participants had to meet the following inclusion criteria: (1) female, age 18 yr or older; (2) self-identification as African-American; (3) diagnosed with SLE and fulfilling at least four of the revised American College of Rheumatology classification criteria for SLE (Hochberg, 1997); (4) ambulatory; (5) experiencing fatigue for the past 3 mo or longer as indicated by a rating of at least 4 (moderate fatigue) on a Fatigue Visual Analog Scale ranging from 0 to 10, with 10 being the most fatigue (Piper et al, 2008); (6) sedentary (exercise <3 times per week for 30 min in the past 6 mo); (7) functionally literate (i.e., able to read and follow exercise directions in English); and (8) having permission from their physician to participate in the study.…”

Successes, challenges and lessons learned: Community-engaged research with South Carolina's Gullah population

“…The SLEIGH study has grown to include 237 patients with lupus, 166 unrelated controls and 220 family-member controls to date. Findings from SLEIGH to date suggest a higher than predicted prevalence of multiplex families, with 26.6 per cent of patients coming from multi-affected families, and a significantly lower age at lupus diagnosis in the offspring of a parent with lupus, which could be attributed to genetic ‘anticipation’ (Kamen et al 2008). There is also a high prevalence of autoantibody seropositivity in first-degree relatives of patients, with a notable 35 per cent of all SLEIGH first-degree relatives testing positive for antinuclear antibodies (ANA) at a significant titre of ≥ 1:120.…”

“…There is also a high prevalence of autoantibody seropositivity in first-degree relatives of patients, with a notable 35 per cent of all SLEIGH first-degree relatives testing positive for antinuclear antibodies (ANA) at a significant titre of ≥ 1:120. One of the investigations into potential environmental triggers of autoimmunity led to the discovery of an alarming 95 per cent prevalence of vitamin D deficiency among Gullah AAs, which subsequently led to further studies into the impact of vitamin D deficiency on immune and bone health (Ben-Zvi et al 2010; Kamen et al 2008). A clinical trial providing oral vitamin D to patients with SLE found that higher than expected doses of vitamin D are required to achieve normal levels, and that fortunately these doses are safe and well tolerated.…”