The Five-Factor Score Revisited: Assessment of Prognoses of Systemic Necrotizing Vasculitides Based on the French Vasculitis Study Group (FVSG) Cohort
The 1996 Five-Factor Score (FFS) for systemic necrotizing vasculitides (polyarteritis nodosa [PAN], microscopic polyangiitis [MPA], and Churg-Strauss syndrome [CSS]) is used to evaluate prognosis at diagnosis. In the current study we revisited the FFS, this time including Wegener granulomatosis (WG).
We analyzed clinical, laboratory, and immunologic manifestations present at diagnosis of systemic necrotizing vasculitides for 1108 consecutive patients registered in the French Vasculitis Study Group database. All patients met the American College of Rheumatology and Chapel Hill nomenclature criteria. Univariable and multivariable analyses yielded the 2009 FFS for the 4 systemic necrotizing vasculitides.
Overall mortality was 19.8% (219/1108); mortality for each of the SNV is listed in descending order: MPA (60/218, 27.5%), PAN (86/349, 24.6%), CSS (32/230, 13.9%), and WG (41/311, 13.2%) (p < 0.001). The following factors were significantly associated with higher 5-year mortality: age >65 years, cardiac symptoms, gastrointestinal involvement, and renal insufficiency (stabilized peak creatinine ≥150 μmol/L). All were disease-specific (p < 0.001); the presence of each was accorded +1 point. Ear, nose, and throat (ENT) symptoms, affecting patients with WG and CSS, were associated with a lower relative risk of death, and their absence was scored +1 point (p < 0.001). Only renal insufficiency was retained (not proteinuria or microscopic hematuria) as impinging on outcome. According to the 2009 FFS, 5-year mortality rates for scores of 0, 1, and ≥2 were 9%, 21% (p < 0.005), and 40% (p < 0.0001), respectively.
The revised FFS for the 4 systemic necrotizing vasculitides now comprises 4 factors associated with poorer prognosis and 1 with better outcome. The retained items demonstrate that visceral involvement weighs heavily on outcome. The better WG prognosis for patients with ENT manifestations, even for patients with other visceral involvement, compared with the prognosis for those without ENT manifestations, probably reflects WG phenotype heterogeneity.