Table 2

Seasonality and disease activity in kidney biopsy-proven AAV, as measured by EGFR and proteinuria

MPAGPA
eGFRuPCReGFRuPCR
Autumn37.6±35.6150 (76–233)33.3±28.3121 (40–451)
Winter28.6±24.6112 (76–290)32.5±24.8139 (104–176)
Spring28.1±18.0167 (101–392)37.4±27.8110 (69–190)
Summer21.8±13.8152 (77–326)35.3±30.6244 (115–281)
P valueNSNSNSNS
  • Mean±SD values eGFR (mL/min/1.73 m2) and median (IQR) of urine protein:creatinine ratio (mg/mmol).

  • AAV, ANCA-associated vasculitis; eGFR, estimated glomerular filtration rate; GPA, granulomatosis polyangiitis; MPA, microscopic polyangiitis; UPCR, urine protein to creatinine ratio.