Age at Dx, Signs Differ in Hispanics

TOPLINE:

Hispanic patients with dermatomyositis are diagnosed at a younger age, exhibit different clinical manifestations, and are more likely to have a different autoantibody than non-Hispanic patients, researchers report.

METHODOLOGY:

• A retrospective cohort study included 207 adults with dermatomyositis (79.7% women) at the University of Miami, Coral Gables, Florida, from 2010 to 2022.
• A total of 95 patients were Hispanic (mean age, 54.6 years), and 112 were non-Hispanic (mean age, 58.1 years). Serological data were available for 20 and 48 patients in the two groups, respectively.
• Researchers analyzed the demographic, laboratory, and clinical characteristics of the patients.

TAKEAWAY:

• Hispanic patients with dermatomyositis were diagnosed at a significantly younger age than non-Hispanic patients (mean 48.3 vs 52.4 years; P = .02).
• Hispanic patients had a higher prevalence of mechanic’s hands (14.7% vs 5.4%; P = .02), a lower prevalence of the Gottron sign (31.6% vs 50.9%; P = .005), and were less likely to receive colonoscopy screening (21.1% vs 46.6%; P < .001) and treatment with mycophenolate mofetil (24.2% vs 38.4%; P = .04).
• The most prevalent autoantibody in Hispanic patients was anti-threonyl-transfer RNA synthetase (25% vs 2.1% in non-Hispanic patients), and in non-Hispanics, it was anti-transcription intermediary factor 1γ (18.8% vs 10% in Hispanics).
• Malignancy rates in Hispanic and non-Hispanic patients were 17.9% vs 9.8%, respectively, which was not a significant difference. The mortality rate (2.1% in Hispanics vs 2.7% in non-Hispanics) was similar in both groups.

IN PRACTICE:

The study results provided “valuable insights for diagnosis, management, and addressing disparities,” the authors wrote. “Hispanic patients were slightly younger at diagnosis compared with previous US-based studies, possibly indicating earlier clinical onset. Clinical differences in Gottron signs and mechanic’s hands in Hispanic patients also suggest variations in disease manifestation, which may influence the use of mycophenolate mofetil,” they added. They also recommended interventions to address lower rates of colonoscopy screening in Hispanic patients.

SOURCE:

The study was led by Rachel R. Lin, BS, University of Miami Leonard M. Miller School of Medicine in Miami, and was published online on August 14 in JAMA Dermatology.

LIMITATIONS:

The study’s limitations included a small sample size, the retrospective design, and potential bias from incomplete clinical records or a lack of access to a standardized dermatomyositis assessment tool. The low number of available serologic test results also limited the analysis, and the binary classification of Hispanic ethnicity may not fully capture diversity within this group.

DISCLOSURES:

The study funding source was not disclosed. Two authors received personal fees and grants from pharmaceutical companies outside this work. Other authors reported no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.