Pathologic features can provide valuable information for determining prognosis in IgA nephropathy (IgAN). However, it is uncertain whether the Oxford classification, a new classification of IgAN, can predict renal outcome better than previous ones. We conducted a retrospective cohort study in 500 patients with biopsy-proven IgAN between January 2002 and December 2010 to compare the ability of the Haas and the Oxford classifications to predict renal outcome. Primary outcome was a doubling of the baseline serum creatinine concentration (D-SCr). During a mean follow-up of 68 months, 52 (10.4%) and 35 (7.0%) developed D-SCr and end-stage renal disease, respectively. There were graded increases in the development of D-SCr in the higher Haas classes. In addition, the primary endpoint of D-SCr occurred more in patients with the Oxford M and T lesions than those without such lesions. In multivariate Cox regression analyses, the Haas class V (HR, 12.19; P =.002) and the Oxford T1 (hazard ratio [HR], 6.68; P <.001) and T2 (HR, 12.16; P <.001) lesions were independently associated with an increased risk of reaching D-SCr. Harrell's C index of each multivariate model with the Haas and the Oxford classification was 0.867 (P =.015) and 0.881 (P =.004), respectively. This was significantly higher than that of model with clinical factors only (C = 0.819). However, there was no difference in C-statistics between the 2 models with the Haas and the Oxford classifications (P =.348). This study suggests that the Haas and the Oxford classifications are comparable in predicting progression of IgAN.
Bibliographical noteFunding Information:
This study was supported by a faculty research grant of Yonsei University College of Medicine for 2012 (6-2012-0033); and by a grant of the Korea Healthcare Technology R&D Project, Ministry of Health and Welfare, Republic of Korea (A102065).
All Science Journal Classification (ASJC) codes
- Pathology and Forensic Medicine