Ethnic differences for developing rheumatic fever in a low-income group living in Hawaii.

UNLABELLED: The risk factors responsible for acute rheumatic fever (ARF) are complex, in part, because group A streptococcus (GAS) infection is a prerequisite for this disease. We attempted to differentiate socioeconomic from genetic risk factors by studying subjects in a Hawaii pediatric cardiology clinic who qualified for Medicaid. This ethnically diverse group was unique because they maintained a low socioeconomic but generally healthy lifestyle with more limited risks than those living in extremely impoverished conditions. METHODS: Questionnaires were administered to consenting subjects in the clinic, who were divided into those diagnosed with ARF (n = 26) and those with other (primarily congenital) heart diseases (n = 41). RESULTS: The socioeconomic status of the ARF and non-ARF groups was lower than that of the Hawaii population in general, and little differences were noted between the groups. The ARF group, however, had slightly larger household sizes and more children than the non-ARF group. The greatest difference was in ethnicity. By the Fisher exact test, the number of Polynesians belonging to the ARF group was significantly greater than all other ethnicities (P = .005). Polynesians had an odds ratio > 4.80 of developing ARF, which increased to 6.33 when number of children per household was considered. CONCLUSION: The potential contribution of genetic predisposing factors for developing ARF was analyzed in subjects living in a homogeneously low socioeconomic level relative to the general Hawaii population. Polynesians were at highest risk when compared to other ethnicities living in similar socioeconomic conditions.

Visiting consultant clinics to study prevalence rates of juvenile rheumatoid arthritis and childhood systemic lupus erythematosus across dispersed geographic areas.

OBJECTIVE: Visiting consultant clinics (VCC) may provide pediatric rheumatologic care to children in rural populations, but the clinical demands have not been studied. We studied whether these clinics could be effective in determining prevalence rates of rheumatic illness like juvenile rheumatoid arthritis (JRA) and childhood systemic lupus erythematosus (SLE) across large dispersed geographic areas. METHODS: The study population included children diagnosed with JRA or SLE at the only civilian pediatric rheumatology center in the State of Hawaii. Prevalence rates of these illnesses were then calculated for the urban and more rural neighbor island areas. VCC and prevalence data were calculated over a 10-year period. RESULTS: We found a lower prevalence of JRA in the urban area (38.3 per 100,000) when compared to the rural neighbor islands (63.2 per 100,000). However, an equivalent prevalence of SLE was found in the urban (24.0 per 100,000) and neighboring islands (21.8 per 100,000). Clinical demands increased significantly with the success of the VCC, and with an increase in pediatric rheumatologic staffing. CONCLUSION: We found an increased prevalence of JRA in rural areas when compared to urban areas. Similar prevalence rates of SLE suggested the finding was not due to referral bias alone. VCC are useful to estimate disease prevalence over large areas, and therefore make it possible to identify areas at greater risk. Further investigations are needed to elucidate the possible environmental and genetic factors that may explain the regional differences in JRA prevalence.

Ethnic differences in risk for pediatric rheumatic illness in a culturally diverse population.

OBJECTIVE: To analyze the differences of occurrence of pediatric rheumatic disease among various ethnic groups in a culturally diverse isolated geographic area. METHODS: A retrospective study of pediatric rheumatic diseases in a multiethnic area during a 6 year period. RESULTS: A group of 922 patients was categorized based on predominant ethnicity, and their risk of having acute rheumatic fever (ARF), juvenile rheumatoid arthritis (JRA), and systemic lupus erythematosus (SLE) was studied. Odds ratios (OR) were computed for each illness with Caucasians as the reference group. Results indicated that Polynesians were overrepresented among patients with ARF, having elevated OR that were significantly different from Caucasians (22.5-120.7, p < 0.0001). For SLE, the highest OR were obtained for Samoans, Filipinos, and Japanese. In contrast, for JRA, Filipinos and Japanese had OR less than one, and no Samoans were diagnosed with JRA, possibly indicating a protective effect against developing JRA. CONCLUSION: This unique retrospective study examined the ethnic variations of expression of certain rheumatic diseases in an isolated region. Results reveal that certain ethnic groups are at risk for ARF and SLE, but are protected against JRA. These findings suggest investigating possible immunogenetic similarities and differences in these illnesses.