Knowledge about systemic lupus erythematosus (SLE) outcomes among US Asians is lacking. We examined SLE disease activity, severity, and damage among Asians of primarily Chinese and Filipino descent in a multiethnic cohort.
California Lupus Epidemiology Study (CLUES, n=328) data were analyzed. Data were collected in English, Cantonese, Mandarin or Spanish, using validated instruments for disease activity (Systemic Lupus Erythematosus Disease Activity Index), disease severity (Lupus Severity Index [LSI]) and disease damage (Systemic Lupus International Collaborating Clinics Damage Index). We assessed differences in SLE outcomes among racial/ethnic groups using multivariable linear regression including interaction terms for age at diagnosis and race/ethnicity.
Asians were the largest racial/ethnic group (38%; [Chinese=22%; Filipino=9%; Other=7%]). Average age at diagnosis (years) was younger among Asians (27.9), particularly Filipinos (22.2), compared with Whites (29.4) and Blacks (34.0). After adjustment, disease activity and damage were not significantly different across groups. Disease severity among Asians was significantly higher than Whites (LSI 7.1 vs 6.5; p<0.05) but similar to Blacks and Hispanics. Early age at diagnosis was associated with greater organ damage among Asians, Blacks, and Hispanics, but not Whites.
SLE was more severe among US Asians compared to Whites. Filipinos were affected at strikingly young ages. Asians and non-White groups with younger age at diagnosis had greater organ damage than Whites. Such racial/ethnic distinctions suggest the need for heightened clinical awareness to improve health outcomes among Asians with SLE. Further study of SLE outcomes across a range of US Asian subgroups is important.