Risk factors for serious infection in patients with microscopic polyangiitis: results from the reveal cohort

Background Many studies have reported risk factors for infection in ANCA-associated vasculitis, but the consistency of these risk factors varies between studies [1-5] . In addition, few reports have focused specifically on patients with microscopic polyangiitis (MPA) or have focused on the impact of glucocorticoids (GC) reduction on the risk of infection. Objectives In this study, we aimed to examine risk factors of serious infections (SI) in patients with MPA in the REVEAL cohort, a Japanese multicenter cohort. As one of the risk factors, we also focused on the pace of GC reduction. Methods 181 MPA patients hospitalized for induction therapy and followed for at least three months were recruited from the REVEAL cohort. We evaluated the demographic, clinical, and laboratory findings, and treatments. To assess the pace of GC reduction, GC doses at 3, 12, and 24 months were extracted, and the ratio of each to the initial dose was calculated. Univariate analysis and COX regression analysis were performed to identify risk factors for SI, defined as infections requiring hospitalization in these patients. Gray test was performed for the comparison of the cumulative incidence of SI between groups. Results There were 115 patients without SI and 66 patients with SI. Univariate analysis showed that age, smoking index, CRP, and GC dose ratio (3 months/initial dose) were associated with SI. In the COX regression analysis (shown in Table 1), age, CRP, and GC dose ratio (3 months/initial dose) were identified as significant risk factors (p values are <0.005, <0.005, and 0.04, respectively). In addition, the group with GC dose ratio (3 months/initial dose) ≥ 0.4 had significantly higher cumulative incidence of SI than the other group (p=0.032) (shown in Figure 1). Conclusion Age, CRP, and GC dose ratio (3 months/initial dose) were identified as risk factors for SI in MPA patients. References [1]Lai QY, Ma TT, Li ZY, et al. Predictors for mortality in patients with antineutrophil cytoplasmic autoantibody-associated vasculitis: a study of 398 Chinese patients. J Rheumatol. 2014;41:1849–55. [2]Little MA, Nightingale P, Verburgh CA, et al. Early mortality in systemic vasculitis: relative contribution of adverse events and active vasculitis. Ann Rheum Dis. 2010;69:1036–43. [3]Mohammad AJ, Segelmark M, Smith R, et al. Severe Infection in Antineutrophil Cytoplasmic Antibody-associated Vasculitis. J Rheumatol. 2017;44:1468–75. [4]Yoo J, Jung SM, Song JJ, et al. Birmingham vasculitis activity and chest manifestation at diagnosis can predict hospitalised infection in ANCA-associated vasculitis. Clin Rheumatol. 2018;37:2133–41. [5]Yang L, Xie H, Liu Z, et al. Risk factors for infectious complications of ANCA-associated vasculitis: a cohort study. BMC Nephrol. 2018;19:138. Table 1 Odds ratio [95% CI] p value Age (years ) 1.08 [1.04-1.12] <0.005 Sex (Female ) 0.57 [0.30-1.07] 0.08 Smoking index 1.00 [1.00-1.00] 0.26 CRP 1.08 [1.03-1.13] <0.005 GC dose ratio (3 months/initial dose ) 6.53 [1.08-39.52] 0.04 Figure 1 Acknowledgements None. Disclosure of Interests Atsushi Manabe: None declared, Keiichiro Kadoba: None declared, Ryosuke Hiwa: None declared, Mikihito Shoji: None declared, Mirei Shirakashi: None declared, Hideaki Tsuji: None declared, Koji Kitagori: None declared, Syuji Akizuki Grant/research support from: Asahi Kasei, Ran Nakashima Speakers bureau: Astellas, Boehringer Ingelheim, Asahi Kasei, Japan Blood Products Organization, Nihon Pharmaceutical, Grant/research support from: Boehringer Ingelheim, Medical & Biological Laboratories Co., Ltd., Hajime Yoshifuji: None declared, Wataru Yamamoto: None declared, Ayana Okazaki: None declared, Shogo Matsuda Speakers bureau: Abbvie, Takuya Kotani Speakers bureau: Abbvie, Bristol Myers Squibb, Chugai, Eisai, Eli Lilly, Pfizer, Takaho Gon: None declared, Ryu Watanabe Speakers bureau: Asahi Kasei, Eli Lilly, Chugai, GSK, Sanofi, Grant/research support from: AbbVie, Motomu Hashimoto Speakers bureau: Eli Lilly, Chugai, Tanabe-Mitsubishi, Bristol Myers Squibb, Eisai, Grant/research support from: AbbVie, Asahi Kasei, Astellas, Bristol Myers Squibb, Eisai, Daiichi Sankyo, Eli Lilly, Novartis, Akio Morinobu Speakers bureau: Chugai, Eli Lilly, Eisai, Bristol Myers Squibb, Tanabe-Mitsubishi, Astellas, Grant/research support from: Asahi Kasei, Chugai, Tanabe-Mitsubishi, Taisho, Eisai.