In the JournalsPerspective

Racial, ethnic minorities at greater risk for severe lupus manifestations

Black, Asian, Pacific islander and Hispanic patients with systemic lupus erythematosus are at a greater risk for developing more renal, neurologic and hematologic manifestations compared with white patients, and also demonstrate lupus nephritis, thrombocytopenia and antiphospholipid syndrome sooner, according to data published in Arthritis Care & Research.

“There are currently few studies exploring racial/ethnic differences in the clinical presentation of SLE or in the development of severe disease manifestations subsequent to SLE diagnosis,” Ernest Maningding, MD, of the University of California, San Francisco, and colleagues wrote. “Previous epidemiologic studies suggest that in comparison to whites, blacks have a more severe presentation of symptoms at the time of diagnosis of SLE and a worse overall prognosis. However, no studies to date have analyzed racial/ethnic differences in manifestations of SLE across the four major racial/ethnic populations in the U.S., including among [Asians/Pacific islanders] and Hispanics.”

To evaluate the differences in SLE manifestations among racial and ethnic minorities, Maningding and colleagues reviewed data from the California Lupus Surveillance Project (CLSP), one of four lupus registries funded by the CDC in the United States. Created through a partnership between the California Department of Public Health and the University of California, San Francisco, the CLSP is a population-based registry of patients with SLE living in San Francisco from 2007 to 2009, with a special focus on Asian, Pacific islander and Hispanic residents.

 
Black, Asian, Pacific islander and Hispanic patients with SLE are at a greater risk for developing more renal, neurologic and hematologic manifestations compared with white patients, and also demonstrate lupus nephritis, thrombocytopenia and antiphospholipid syndrome sooner, according to data.
Source: Adobe

For their study, the researchers identified 724 patients with SLE for inclusion. Among these patients, 26.2% were white, 18.8% were black, 36.9% were Asian or Pacific islander and 15.5% identified as Hispanic. Of those who identified as Asian or Pacific islander, 49.4% were Chinese, 1.54% were Filipino and 6.7% were Vietnamese.

In addition, 50.9% included Hispanics did not specify any ethnic origin, while 31.3% described themselves as South or Central American and 13.4% were Mexican.

Maningding and colleagues calculated prevalence ratios (PR) for SLE manifestations using Poisson regression models stratified by race/ethnicity and adjusted for sex, age at diagnosis and disease duration. In addition, they analyzed severe manifestation onset following diagnosis using KaplanMeier methods to examine timetoevent. Cox proportional hazards regressions were used to estimate hazard ratios.

According to the researchers, black (PR = 1.74; 95% CI, 1.4-2.16), Asian and Pacific islander (PR = 1.68; 95% CI, 1.38-2.05) and Hispanic (PR = 1.35; 95% CI, 1.05-1.74) patients with SLE demonstrated an increased prevalence of renal manifestations, compared with whites. In addition, black patients had increased prevalence of neurologic manifestations (PR = 1.49; 95% CI, 1.12-1.98), while blacks (PR = 1.09; 95% CI, 1.04-1.15) and Asians and Pacific islanders (PR = 1.07; 95% CI, 1.01-1.13) demonstrated an increased prevalence of hematologic manifestations.

Blacks, Asians, Pacific islanders and Hispanics also demonstrated a higher risk for lupus nephritis and thrombocytopenia, compared with whites. Asian and Pacific islander (HR = 2.5; 95% CI, 1.4-4.4) and Hispanic (HR = 2.6; 95% CI, 1.3-5.1) patients had a higher risk for antiphospholipid syndrome.

“This study found important differences in the characteristics and progression of SLE between racial/ethnic minority groups and whites,” Maningding and colleagues wrote. “It is the first study to use rigorous epidemiologic methods to compare SLE manifestations across four racial/ethnic groups, including [Asians/Pacific islanders] and Hispanics, two understudied populations.”

“Data collected in this study support the importance of increased awareness of SLE and its accelerated progression by clinicians for these racial/ethnic groups,” they added. “These data also advocate for greater resource allocation on early diagnosis and treatment in these populations.” – by Jason Laday

Disclosures : The researchers report funding from the CDC and NIH.

Black, Asian, Pacific islander and Hispanic patients with systemic lupus erythematosus are at a greater risk for developing more renal, neurologic and hematologic manifestations compared with white patients, and also demonstrate lupus nephritis, thrombocytopenia and antiphospholipid syndrome sooner, according to data published in Arthritis Care & Research.

“There are currently few studies exploring racial/ethnic differences in the clinical presentation of SLE or in the development of severe disease manifestations subsequent to SLE diagnosis,” Ernest Maningding, MD, of the University of California, San Francisco, and colleagues wrote. “Previous epidemiologic studies suggest that in comparison to whites, blacks have a more severe presentation of symptoms at the time of diagnosis of SLE and a worse overall prognosis. However, no studies to date have analyzed racial/ethnic differences in manifestations of SLE across the four major racial/ethnic populations in the U.S., including among [Asians/Pacific islanders] and Hispanics.”

To evaluate the differences in SLE manifestations among racial and ethnic minorities, Maningding and colleagues reviewed data from the California Lupus Surveillance Project (CLSP), one of four lupus registries funded by the CDC in the United States. Created through a partnership between the California Department of Public Health and the University of California, San Francisco, the CLSP is a population-based registry of patients with SLE living in San Francisco from 2007 to 2009, with a special focus on Asian, Pacific islander and Hispanic residents.

 
Black, Asian, Pacific islander and Hispanic patients with SLE are at a greater risk for developing more renal, neurologic and hematologic manifestations compared with white patients, and also demonstrate lupus nephritis, thrombocytopenia and antiphospholipid syndrome sooner, according to data.
Source: Adobe

For their study, the researchers identified 724 patients with SLE for inclusion. Among these patients, 26.2% were white, 18.8% were black, 36.9% were Asian or Pacific islander and 15.5% identified as Hispanic. Of those who identified as Asian or Pacific islander, 49.4% were Chinese, 1.54% were Filipino and 6.7% were Vietnamese.

In addition, 50.9% included Hispanics did not specify any ethnic origin, while 31.3% described themselves as South or Central American and 13.4% were Mexican.

Maningding and colleagues calculated prevalence ratios (PR) for SLE manifestations using Poisson regression models stratified by race/ethnicity and adjusted for sex, age at diagnosis and disease duration. In addition, they analyzed severe manifestation onset following diagnosis using KaplanMeier methods to examine timetoevent. Cox proportional hazards regressions were used to estimate hazard ratios.

According to the researchers, black (PR = 1.74; 95% CI, 1.4-2.16), Asian and Pacific islander (PR = 1.68; 95% CI, 1.38-2.05) and Hispanic (PR = 1.35; 95% CI, 1.05-1.74) patients with SLE demonstrated an increased prevalence of renal manifestations, compared with whites. In addition, black patients had increased prevalence of neurologic manifestations (PR = 1.49; 95% CI, 1.12-1.98), while blacks (PR = 1.09; 95% CI, 1.04-1.15) and Asians and Pacific islanders (PR = 1.07; 95% CI, 1.01-1.13) demonstrated an increased prevalence of hematologic manifestations.

Blacks, Asians, Pacific islanders and Hispanics also demonstrated a higher risk for lupus nephritis and thrombocytopenia, compared with whites. Asian and Pacific islander (HR = 2.5; 95% CI, 1.4-4.4) and Hispanic (HR = 2.6; 95% CI, 1.3-5.1) patients had a higher risk for antiphospholipid syndrome.

“This study found important differences in the characteristics and progression of SLE between racial/ethnic minority groups and whites,” Maningding and colleagues wrote. “It is the first study to use rigorous epidemiologic methods to compare SLE manifestations across four racial/ethnic groups, including [Asians/Pacific islanders] and Hispanics, two understudied populations.”

“Data collected in this study support the importance of increased awareness of SLE and its accelerated progression by clinicians for these racial/ethnic groups,” they added. “These data also advocate for greater resource allocation on early diagnosis and treatment in these populations.” – by Jason Laday

Disclosures : The researchers report funding from the CDC and NIH.

    Perspective
    David A. McLain

    David A. McLain

    This is an important study as it identifies — in a retrospective design — the differences in lupus among races and ethnic groups which included whites, blacks, Asian/Pacific Islanders (APIs), and Hispanics.

    The authors found no statistically significant differences in prevalence between racial/ethnic minority groups and whites for the mucocutaneous, serositis, cardiovascular, pulmonary, gastrointestinal, musculoskeletal or serologic manifestation categories. Hispanics had less neuropsychiatric manifestations than the other groups (significant at P<0.1) and APIs exhibited more antiphospholipid syndrome than other groups but the incidence difference was not significant.

    The authors found that for racial and ethnic minorities, the risk of lupus nephritis was greatest during the first year following diagnosis of SLE. Among the minorities studied, APIs had the highest incidence of lupus nephritis. While this study did not address socioeconomic factors in the development of lupus nephritis, previous studies have found a correlation between socioeconomics and lupus nephritis in blacks and Hispanics.

    In this study, APIs had the highest incidence of lupus nephritis but also the highest average income and education levels among the minorities studied in San Francisco County. All racial and ethnic groups, including whites, were at greatest risk of antiphospholipid syndrome and thrombocytopenia during the first year following SLE diagnosis. Additionally, the authors found that men have a higher incidence of lupus nephritis and thrombocytopenia at the time of diagnosis compared with women.

    One of the possible explanations for minorities and men having more severe disease at presentation is that these groups present at a more advanced stage at the time of diagnosis; contrary to this explanation would be their finding that the age of onset was not statistically different among the groups.

    • David A. McLain, MD, FACP, FACR
    • Executive director, Alabama Society for the Rheumatic Diseases
      Symposium director, Congress of Clinical Rheumatology

    Disclosures: McLain reports no relevant financial disclosures.