The relationship between the modified National Institute of Health activity and chronicity scoring system, and the long-term prognosis for lupus nephritis: A retrospective single-center study
Shiori Nakagawa, Tadashi Toyama, Yasunori Iwata, Megumi Oshima, Hisayuki Ogura, Kōichi Sato, Yuta Yamamura, Taro Miyakawa, Shinji Kitajima, Akinori Hara, Norihiko Sakai, Miho Shimizu, Takashi Wada
Abstract
Background The revision of International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification guidelines for lupus nephritis (LN) was suggested by a working group, who recommended a modified National Institute of Health (NIH) activity and chronicity scoring system to evaluate active and chronic LN lesions. However, whether this approach was useful for estimating long-term prognosis for LN patients is unclear. Methods We conducted a retrospective cohort study in Japanese subjects with biopsy-proven LN, between 1977 and 2018. Pathologic lesions were evaluated based on ISN/RPS 2003 classifications and the modified NIH scoring system. Patients were grouped by activity index (low, 0–5; moderate, 6–11; high, 12–24), and chronicity index (low, 0–2; moderate, 3–5; high, 6–12). The primary outcome was a composite of end-stage kidney disease (ESKD) or all-cause death, and the secondary outcome was ESKD alone. Results Sixty-six subjects with a median age of 31 years were included. During median follow-up (11.5 years), 15 patients reached the primary outcome: 10 had ESKD, four had died, and one had ESKD and died. Kaplan–Meier analysis showed that the cumulative primary outcome incidence increased with a higher chronicity index (log-rank trend p < 0.001). From multivariable survival analysis, moderate (hazard ratio [HR] 6.17, 95% confidence interval [CI] 1.14 to 33.20; p = 0.034) and high chronicity indices (HR 20.20, 95% CI 1.13 to 359.82; p = 0.041) were risk factors for the primary outcome. Conclusion Moderate and high chronicity indices were associated with an increased ESKD risk for LN.