Epidemiological and clinical insights into Behçet's disease in Japan: a 2019 nationwide analysis

Clinical Snapshot

Key Findings

• P Value: Not reported

• Effect Size: 53.2% female predominance overall, with distinct sex-based clinical phenotypes

• Primary Outcome: Sex-based differences in clinical manifestations: males more likely to have serious organ involvement (ocular, vascular, CNS), females more mucocutaneous and articular symptoms

• Nnt Or Sensitivity: 93.8% of patients receiving pharmacological treatment, 44.3% on corticosteroids, 50.9% on colchicine

• Confidence Interval: Not reported

Clinical Application

High feasibility for clinical application of sex-based risk stratification and treatment patterns Relevant for Australian rheumatologists and ophthalmologists; infliximab and adalimumab PBS-listed for Behçet's disease, supporting similar treatment approaches Patients with Behçet's disease in developed healthcare systems with access to biologics

Abstract

OBJECTIVES: To clarify contemporary epidemiological and clinical trends of Behçet's disease in Japan by analysing the 2019 National Database of Designated Intractable Diseases (MHLW), describing patient demographics, organ involvement, impact on daily life, and treatment patterns. METHODS: This study analysed the 2019 data from the National Database of Designated Intractable Diseases of Japan, provided by the Japanese Ministry of Health, Labour and Welfare. We focused on age distribution, symptom frequency, daily life impact, and treatment trends. RESULTS: In the 2019 database, 10 406 patients with BD were registered. The median age was 55 years, with a higher proportion of women affected (53.2%). Serious manifestations such as ocular, vascular, and central nervous system involvement were more frequent in males, whereas females showed more mucocutaneous and articular symptoms, representing mild forms of the disease. Pharmacological treatment was common (93.8%), with corticosteroids (44.3%), colchicine (50.9%), infliximab (17.0%), and adalimumab (9.6%) being frequently used. BD significantly affected daily life, with nearly one-third experiencing impaired mobility or depression. CONCLUSIONS: This nationwide analysis highlighted sex-based differences in clinical features and found that BD continues to substantially affect quality of life. The widespread use of biologics suggests a shift in therapeutic strategies.

References

1. 1.Mizuki, Y., Horita, N., Takeno, M., Meguro, A., Kirino, Y., Kawagoe, T., Sakono, T., Ishihara, M., Ohno, S., & Mizuki, N. (2026). Epidemiological and clinical insights into Behçet's disease in Japan: a 2019 nationwide analysis. Modern Rheumatology. https://doi.org/10.1093/mr/roaf103