Session Information
Date: Wednesday, November 8, 2017
Title: Systemic Sclerosis, Fibrosing Syndromes and Raynaud's – Clinical Aspects and Therapeutics III
Session Type: ACR Concurrent Abstract Session
Session Time: 11:00AM-12:30PM
Background/Purpose:
Retrospective cohorts have demonstrated that African Americans (AAs) with scleroderma are more likely to have severe disease and higher mortality than non-AAs. A prior study concluded that this excess risk was not fully explained by differences in rates of diffuse disease and autoantibody status (Gelber 2013). Our study sought to further evaluate this risk among matched AAs and non-AAs at our site.
Methods:
A single-center, retrospective study comparing AA and non-AA patients with scleroderma was performed. Patients were evaluated by the senior author between 2008 and 2016. AA and non-AAs were matched based on sex, age at first visit, date of first visit, disease duration at first visit, and limited vs. diffuse cutaneous disease. Demographic, serologic, and clinical features were compared. Mortality risks were assessed in an unadjusted manner and by a Cox proportional hazards model with covariates of race, median household income by ZIP code, marital status, education level, employment status, and insurance type.
Results:
AAs comprised 203 of the 402 patients analyzed. The groups were statistically similar regarding all factors by which they were matched. Table 1 shows our findings. AAs had significantly reduced FVC and DLCO, more severe fibrosis per CT, a higher prevalence of any type of pulmonary hypertension, and more severe cardiac involvement. As expected, autoantibody profile statistically differed among the two groups (p<0.001). Death during follow-up was 21.2% in AAs vs. 11.1% in non-AAs (p=0.006). AA status demonstrated an unadjusted hazard ratio for death during follow-up of 2.037 (p=0.007), but when adjusted for the aforementioned socioeconomic covariates, the hazard ratio of AA status declined to 1.256 (95% CI 0.494 – 3.191, p=0.633). The only statistically significant covariate was median income in thousands of dollars by ZIP code, with a hazard ratio of 0.983 (95% CI 0.968 – 0.999, p=0.033).
Conclusion:
African American patients with scleroderma have more severe pulmonary disease and a higher unadjusted risk of mortality than matched non-African Americans. Adjusting for available socioeconomic factors, African American race was not a significant risk factor for mortality, but lower median household income by ZIP code was an independent risk factor for increased mortality.
| African American (n = 203) | Non-African American (n = 199) | p-value | |
| Sex (female) | 176 (86.7) | 173 (86.9) | 0.944 |
| Age at first visit, mean ± SD | 47.4 ± 13.3 | 48.5 ± 13.0 | 0.379 |
| Disease duration at first visit (years), mean ± SD |
7.7 ± 8.1 | 8.3 ± 9.6 | 0.512 |
| SSc type (diffuse) | 97 (47.8) | 81 (40.7) | 0.121 |
| Autoantibody | < 0.001 | ||
| anti-centromere | 15 (7.4) | 43 (21.6) | < 0.001 |
| anti-Scl70 | 43 (21.2) | 41 (20.6) | 0.886 |
| anti-U1RNP | 26 (12.8) | 10 (5.0) | 0.006 |
| isolated nucleolar ANA | 50 (24.6) | 32 (16.1) | 0.033 |
| anti-RNA polymerase III | 7 (3.4) | 29 (14.6) | < 0.001 |
| non-specific SSc ANA | 46 (22.7) | 27 (13.6) | 0.018 |
| negative ANA | 11 (5.4) | 9 (4.5) | 0.680 |
| no result | 5 (2.5) | 8 (4.0) | 0.378 |
| Inflammatory arthritis | 33 (16.3) | 43 (21.6) | 0.171 |
| Tendon rubs | 25 (12.3) | 40 (20.1) | 0.034 |
| Telangiectasia | 39 (19.2) | 101 (50.8) | < 0.001 |
| Calcinosis | 10 (4.9) | 33 (16.6) | < 0.001 |
| Skin score, mean ± SD | 14.1 ± 13.2 | 14.4 ± 12.6 | 0.803 |
| FVC (% predicted), mean ± SD | 68.4 ± 20.4 | 84.1 ± 48.7 | < 0.001 |
| DLCO (% predicted), mean ± SD | 45.8 ± 19.8 | 63.7 ± 20.9 | < 0.001 |
| Fibrosis per CT | 0.002 | ||
| no fibrosis | 38 (18.7) | 60 (30.2) | 0.008 |
| mild/moderate fibrosis | 77 (37.9) | 67 (33.7) | 0.373 |
| severe fibrosis | 22 (10.8) | 6 (3.0) | 0.002 |
| not performed | 66 (32.5) | 66 (33.2) | 0.889 |
| Pulmonary hypertension by right heart catheterization |
42 (20.7) | 25 (12.6) | 0.029 |
| Severe cardiac involvement | 35 (17.2) | 17 (8.5) | 0.009 |
| Renal crisis | 17 (8.4) | 6 (3.0) | 0.021 |
| Death during follow-up | 43 (21.2) | 22 (11.1) | 0.006 |
| Duration from diagnosis to death or end of study (years), mean ± SD |
9.5 ± 7.3 | 9.5 ± 8.9 | 0.920 |
To cite this abstract in AMA style:
Moore DF, Kramer E, Eltaraboulsi R, Steen VD. Morbidity and Mortality of Scleroderma in African Americans [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/morbidity-and-mortality-of-scleroderma-in-african-americans/. Accessed .« Back to 2017 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/morbidity-and-mortality-of-scleroderma-in-african-americans/