Racial differences in scleroderma among women in Michigan

Abstract

Objective. To examine racial differences in disease onset, extent, manifestations, and survival among women with scleroderma.Methods. A retrospective cohort study of women with scleroderma, diagnosed in Michigan between 1980 and 1991, was conducted. Clinical, laboratory, and demographic data were abstracted from the patients' medical records.Results. A total of 514 women with scleroderma were identified: 117 (23%) were black and 397 (77%) were white. Among black women, the mean age at diagnosis was lower (44.5 years versus 51.5 years; P < 0.001) and diffuse disease was more common (49.6% versus 24.9%; P < 0.001) than among white women. The overall incidence of scleroderma was 14.1 per million per year: 22.5 per million per year in black women versus 12.8 per million per year in white women (P < 0.001). Pericarditis (P = 0.009), pulmonary hypertension (P < 0.001), pleural effusions (P = 0.01), myositis (P = 0.02), and an erythrocyte sedimentation rate >40 mmlhour (P < 0.001) were more frequent among black women, while white women were more likely to have digital infarctions (P < 0.001). Survival at 7 years from form October 25, 1996. diagnosis was 72.5% among black women and 77.6% among white women. Age-adjusted survival was significantly reduced among black women (P = 0.033), most likely because of increased diffuse involvement. Survival among those with renal or pulmonary involvement was also significantly reduced.Conclusion. Black women with scleroderma were significantly more likely than white women to develop diffuse disease, be diagnosed at a younger age, have a higher incidence of inflammatory features, and have a worse age-adjusted survival rate.Scleroderma is an uncommon connective tissue disease that is characterized by variable degrees of fibrosis within the skin and internal organs. Previous epidemiologic studies have provided estimates of incidence, prevalence, and mortality, and have identified the various clinical and laboratory manifestations that distinguish the diffuse and limited scleroderma subtypes (1,2). In addition, some investigators have suggested important differences between black and white women with regard to incidence, mortality, case fatality, and extent of disease manifestations (3-5). However, few studies have contained sufficient numbers of both black and white women to completely identify and confirm these observations.As part of a population-based case-control study to identify potential risk factors among women with scleroderma, we recruited a large, racially diverse cohort of women with scleroderma in Michigan (6). During review of their medical records, 74 clinical and laboratory parameters were recorded, as well as demographic information, date of diagnosis, and date of death or last followup examination. These data enabled us to examine racial differences in age at diagnosis, extent of disease, clinical manifestations, incidence of disease, and survival.

Prevalence, incidence, survival, and disease characteristics of systemic sclerosis in a large US population

“…No individual had documentation of the presence of both autoantibodies. ACA positivity was less common among black patients than among white patients (P Ͻ 0.001), as noted by other investigators (32,33), and was less common among male patients than among female patients (P Ͻ 0.001). As expected with this autoantibody pattern and as noted above, diffuse disease was more common in the black population compared with the non-black population.…”

“…As in other studies, ACAs were less frequent in black patients than in non-black patients (32,33). Of the 20 prevalent cases involving black men (5 of whom had limited disease), no individual had ACA positivity.…”

Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States

“…The b1ack:white ratio was 1.2:l except in young black women, for whom it was 10:1. Similar results were found in a population-based survey of the incidence of scleroderma in women in Michigan (104).…”

Mortality trends in systemic sclerosis in France and USA, 1980–1998: an age-period-cohort analysis

“…Blacks are at higher risk compared with whites [2,4,10]. Laing et al [11] found a higher incidence among black women compared to white women (22.5 versus 12.8 per million per year respectively) and age at diagnosis was approximately 7 years younger among blacks.…”