Characteristics and phenotype heterogeneity in late-onset Behçet's syndrome: a cohort from a referral center in China.

OBJECTIVES

To evaluate the demographics, clinical aspects, and major organ involvement of patients with late-onset Behçet's syndrome (BS) in a tertiary center in China.

METHODS

We conducted a cross-sectional study of consecutive BS patients in Huadong Hospital of Fudan University from September 2012 to January 2020. We compared clinical variables between patients with disease onset before and after 40 years of age. The relative risks (RRs) of clinical variables were calculated between the two age groups. Moreover, a hierarchical cluster analysis was conducted according to 29 variables to determine homogeneous subgroups in patients with late-onset BS.

RESULTS

We enrolled 152 late-onset BS patients, with a median age at onset of 47 years (interquartile range, IQR: 43-52 years). There is a higher prevalence of intestinal ulcers in late-onset BS than in early-onset BS (RR 1.47), but a lower prevalence of ocular involvements (RR 0.54) and folliculitis (RR 0.46). Female sex was associated with genital ulcers, erythema nodosum, and arthritis. Four clusters (C1-C4) were formed. C1 (n = 71), the largest cluster, was defined as the mucocutaneous group, C2 (n = 20) as the arthritis group, C3 (n = 39) as the gastrointestinal group, in which all patients presented with intestinal lesions, and five cases with esophageal ulcers. In C4 (n = 22), showing a mixture of uveitis and vascular lesions, 15 patients presented with uveitis and 8 had vascular lesions, and 1 case had central nervous system lesions.

CONCLUSION

Four phenotype clusters were identified. Patients with skin lesions comprised the largest cluster, while gastrointestinal, panuveitis, and cardiovascular clusters are the most commonly involved organs in late-onset BS patients. Key Points • Our analysis demonstrated the phenotype discrepancy between early and late onset groups. • Four phenotype clusters were identified, with gastrointestinal, panuveitis and cardiovascular clusters representing commonly involved organs.