Analysis of association between segmental glomerulosclerosis and renal function decline in IgA nephropathy / 中华肾脏病杂志

ABSTRACT

Objective:To explore the relationship between segmental glomerulosclerosis and the change of renal function in IgA nephropathy (IgAN).Methods:It was a single-center retrospective cohort study. The patients with biopsy-proven primary IgAN who were hospitalized in Shenzhen Second People's Hospital from January 1, 2011 to December 31, 2018 were included. Participants with a secondary cause of IgAN, without baseline serum creatinine or renal pathology data for Oxford classification, baseline estimated glomerulofiltration rate (eGFR)<30 ml·min -1·(1.73 m 2) -1, follow-up time<6 months, or less than three times measurements of followed-up serum creatinine were excluded. The clinical data, laboratory tests and renal pathology data and so on were collected. Patients were divided into absence of segmental glomerulosclerosis (S0) group and segmental glomerulosclerosis (S1) group according to the Oxford classification. The generalized additive mixed model was used to analyze the associations of segmental glomerulosclerosis and longitudinal renal function decline (Renal function was evaluated by using the eGFR). Results:There were 280 patients included in this study, with 199 patients in S0 group, and 81 patients in S1 group. Compared with S0 group, patients in S1 group exhibited higher levels of triglyceride, serum uric acid as well as 24-hour urinary protein, and a lower level of eGFR, and had higher proportions of tubular atrophy and interstitial fibrosis (T) (all P<0.05). After adjusting for age, gender, mean arterial pressure, 24-hour urinary protein, mesangial hypercellularity (M), endocapillary hypercellularity (E), T and crescent (C) in the generalized additive mixed model, the effect value of S1 (the difference of baseline eGFR between S1 group and S0 group) was -14.09 ml·min -1·(1.73 m 2) -1. For every additional year, the eGFR of S0 group decreased 1.29 ml·min -1·(1.73 m 2) -1 (95% CI 0.47-2.12, P=0.002) in average, and eGFR decline in S1 group had 2.85 ml·min -1·(1.73 m 2) -1 more than that in S0 group [95% CI 1.05-4.64, P=0.002]. Conclusion:Segmental glomerulosclerosis is independently associated with the longitudinal decrease in renal function in patients with IgAN, which suggests therapies targeted for improving the early damages of segmental glomerulosclerosis may be essential to delay the renal function decline progression.