Fig. 3

Relationship between serum TIMP-1 levels and clinical outcomes in the MAAV-EU study. a Serial analysis of serum TIMP-1 and CRP levels in 30 patients [16 microscopic polyangiitis (MPA) and 14 granulomatosis with polyangiitis (GPA)] with AAV receiving maintenance therapy. All patients achieved remission at the time of enrollment. Color lines present relapsed patients (n = 5) and gray lines patients in sustained remission (n = 25). Baseline refers to 6 months after enrollment in patients in sustained remission and at the time of relapse in relapsed patients. The light blue background indicates a low TIMP-1 level (< 150 ng/mL). b Comparison of serum TIMP-1 and CRP levels between sustained remission patients (n = 25) and relapsed patients (n = 5) in both groups 6 and 3 months before baseline and at baseline. Each dot represents one patient. Box plots show the median and IQR. Whiskers indicate the most extreme points within 1.5-fold of the IQR of the box. c Comparison of clinical outcomes in the low TIMP-1 group (< 150 ng/mL 6 months before baseline, n = 15) and high TIMP-1 group (≥ 150 ng/mL, n = 15). **p < 0.01. ***p < 0.001. TIMP-1, tissue inhibitor of metalloproteinase 1; CRP, C-reactive protein; − 6 M, − 6 months; − 3 M, − 3 months; − 1 M, − 1 month; Rem, sustained remission