Ethnic influence in clinical and functional measures of Brazilian patients with spondyloarthritis.

OBJECTIVE: Spondyloarthritides (SpA) can present different disease spectra according to ethnic background. The Brazilian Registry of Spondyloarthritis (RBE) is a nationwide registry that comprises a large databank on clinical, functional, and treatment data on Brazilian patients with SpA. The aim of our study was to analyze the influence of ethnic background in SpA disease patterns in a large series of Brazilian patients. METHODS: A common protocol of investigation was prospectively applied to 1318 SpA patients in 29 centers distributed through the main geographical regions in Brazil. The group comprised whites (65%), African Brazilians (31.3%), and people of mixed origins (3.7%). Clinical and demographic variables and various disease index scores were compiled. Ankylosing spondylitis (AS) was the most frequent disease in the group (65.1%); others were psoriatic arthritis (18.3%), undifferentiated SpA (6.8%), enteropathic arthritis (3.7%), and reactive arthritis (3.4%). RESULTS: White patients were significantly associated with psoriasis (p = 0.002), positive HLA-B27 (p = 0.014), and use of corticosteroids (p < 0.0001). Hip involvement (p = 0.02), axial inflammatory pain (p = 0.04), and radiographic sacroiliitis (p = 0.025) were associated with African Brazilian descent. Sex distribution, family history, and presence of peripheral arthritis, uveitis, dactylitis, urethritis, and inflammatory bowel disease were similar in the 3 groups, as well as age at disease onset, time from first symptom until diagnosis, and use of anti-tumor necrosis factor-α agents (p > 0.05). Schober test and thoracic expansion were similar in the 3 groups, whereas African Brazilians had higher Maastricht Ankylosing Spondylitis Enthesitis Scores (p = 0.005) and decreased lateral lumbar flexion (p = 0.003), while whites had a higher occiput-to-wall distance (p = 0.02). African Brazilians reported a worse patient global assessment of disease (p = 0.011). Other index scores and prevalence of work incapacity were similar in the 3 groups, although African Brazilians had worse performance in the Ankylosing Spondylitis Quality of Life questionnaire (p < 0.001). CONCLUSION: Ethnic background is associated with distinct clinical aspects of SpA in Brazilian patients. African Brazilian patients with SpA have a poorer quality of life and report worse disease compared to whites.

Gender characterization in a large series of Brazilian patients with spondyloarthritis.

An increasing number of women have been diagnosed with spondyloarthritis (SpA) in recent decades. While a few studies have analyzed gender as a prognostic factor of the disease, no studies have addressed this matter with a large number of patients in South America, which is a peculiar region due to its genetic heterogeneity. The aim of the present study was to analyze the influence of gender on disease patterns in a large cohort of Brazilian patients with SpA. A prospective study was carried out involving 1,505 patients [1,090 males (72.4%) and 415 females (27.6%)] classified as SpA according to the European Spondyloarthropaties Study Group criteria who attended at 29 reference centers for rheumatology in Brazil. Clinical and demographic variables were recorded and the following disease indices were administered: Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Radiologic Index (BASRI), Maastricht Ankylosing Spondylitis Enthesitis Score (MASES), and Ankylosing Spondylitis Quality of Life (ASQoL). Ankylosing spondylitis (AS) was the most frequent disease in the group (65.4%), followed by psoriatic arthritis (18.4%), undifferentiated SpA (6.7%), reactive arthritis (3.3%), arthritis associated to inflammatory bowel disease (3.2%), and juvenile SpA (2.9%). The male-to-female ratio was 2.6:1 for the whole group and 3.6:1 for AS. The females were older (p < 0.001) and reported shorter disease duration (p = 0.002) than the male patients. The female gender was positively associated to peripheral SpA (p < 0.001), upper limb arthritis (p < 0.001), dactylitis (p = 0.011), psoriasis (p < 0.001), nail involvement (p < 0.001), and family history of SpA (p = 0.045) and negatively associated to pure axial involvement (p < 0.001), lumbar inflammatory pain (p = 0.042), radiographic sacroiliitis (p < 0.001), and positive HLA-B27 (p = 0.001). The number of painful (p < 0.001) and swollen (p = 0.006) joints was significantly higher in the female gender, who also achieved higher BASDAI (p < 0.001), BASFI (p = 0.073, trend), MASES (p = 0.019), ASQoL (p = 0.014), and patient's global assessment (p = 0.003) scores, whereas the use of nonsteroidal anti-inflammatory drugs (p < 0.001) and biological agents (p = 0.003) was less frequent in the female gender. Moreover, BASRI values were significantly lower in females (p < 0.001). The female gender comprised one third of SpA patients in this large cohort and exhibited more significant peripheral involvement and less functional disability, despite higher values in disease indices.