Predictive Factors of Severe Behçet's disease: A Longitudinal, Prospective Cohort Followed Between 1981-2020.

Introduction: Behçet's disease (BD) is a systemic vasculitis of unknown cause. The spectrum of the disease ranges from mucocutaneous manifestations to other organ diseases with relevant morbidity. Associations between disease severity and male sex, earlier age at onset, and the presence of erythema nodosum have been described.

Objectives: To evaluate clinical factors associated with manifestations of severe disease in a single-center cohort.

Methods: A longitudinal, prospective, unicentric cohort study with patients followed in a specialized outpatient clinic between 1981 and 2020. Severe BD was defined as a Krause total clinical severity score >4 points.

Results: We included 243 patients, of whom 31% were male, with an average follow-up time of 14.6 years. Regarding organ manifestations, all patients had mucous manifestations (N=243, 100%), 133 (55%) skin, 104 (43%) joint, 71 (29%) ocular, 48 (20%) vascular, 47 (19%) neurological, 22 (9%) gastrointestinal and 1 (0.4%) cardiac involvement by BD. One hundred fifty-six (64%) patients were classified as having severe BD. Severe BD was more frequent in men (OR=2.004, p=0.024), increasing with age (OR=1.021 per year, p=0.037), in the presence of skin manifestations (OR=4.711, p<0.001), specifically erythema nodosum (OR=8.381, p<0.001), and pseudofolliculitis (OR=2.910, p<0.001). In the multivariate model, variables independently associated with severe BD were male gender (Adjusted OR=1.961, p=0.047), erythema nodosum (Adjusted OR=8.561, p<0.001) and pseudofolliculitis (Adjusted OR=2.372, p=0.007).

Discussion: Male gender, erythema nodosum, and pseudofolliculitis were independently associated with severe BD forms and therefore should serve as warning signs to the clinician.