Long-term outcome and efficacy of cyclophosphamide therapy in Japanese patients with ANCA-associated microscopic polyangiitis: a retrospective study.
OBJECTIVE
The aim of this study was to elucidate the efficacy of cyclophosphamide (CY) in Japanese patients with antineutrophil cystoplasmic antibody (ANCA)-associated microscopic polyangiitis (MPA).


METHODS
Sixty-four patients, newly diagnosed with ANCA-associated MPA were included in this retrospective study. The patients were divided into two groups based on whether they received combination therapy of CY and corticosteroid (CS) (CY group, n=29) or CS alone (CS group, n=35) for remission induction. The primary outcome was all-cause mortality.


RESULTS
Most patients in the CY group were treated with oral CY. Between the two groups, there were no differences in the baseline characteristics except for a higher proportion of male patients in the CY group. The remission rate was not substantially different between the two groups (86.2% in the CY group vs. 91.4% in the CS group). The survival rate was slightly higher in the CY group than in the CS group (not statistically significant; 0.86 vs. 0.77 at 1 year and 0.73 vs. 0.64 at 5 years, p=0.648). In the CY group, the hazard ratio after adjusting for age, sex, Birmingham vasculitis activity score values, serum albumin levels and C-reactive protein (CRP) levels was 0.657 (95% CI, 0.254-1.699; p=0.386).


CONCLUSIONS
We observed no increased efficacy of CY in ANCA-positive MPA in the Japanese patients, and hence, its efficacy may be limited in these patients.
Department of Nephrology, Iwate Prefectural Central Hospital, Japan.
Izaya
I
Nakaya
Mayumi
M
Yahata
Satoko
S
Takahashi
Tomomi
T
Sasajima
Tsutomu
T
Sakuma
Yugo
Y
Shibagaki
Jun
J
Soma
D000305:Adrenal Cortex Hormones / Q000008:administration & dosage; D000368:Aged; D000369:Aged, 80 and over; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood; D044466:Asian People; D003520:Cyclophosphamide / Q000008:administration & dosage / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008775:Methylprednisolone / Q000008:administration & dosage; D055953:Microscopic Polyangiitis / Q000188:drug therapy* / Q000276:immunology; D008875:Middle Aged; D011239:Prednisolone / Q000008:administration & dosage; D012189:Retrospective Studies; D016896:Treatment Outcome
D000305:Adrenal Cortex Hormones; D019268:Antibodies, Antineutrophil Cytoplasmic; D003520:Cyclophosphamide; D011239:Prednisolone; D008775:Methylprednisolone