Sex disparities in IgA nephropathy: a retrospective study in Chinese patients

Aim The aim of this study was to explore the effect of sex on the clinicopathological features and long-term outcomes of IgAN patients. Methods A total of 1096 adult IgAN patients were divided into male and female groups. Clinicopathological features and risk factors of IgAN patients of different genders were contrasted. The primary endpoint was the combined endpoint of a 50% reduction in estimated glomerular filtration rate (eGFR) and/or end stage renal disease (ESRD: eGFR < 15 mL/min/1.73 m(2)or dialysis). The effect of gender on prognosis of IgAN was assessed using Kaplan-Meier and Cox proportional hazards models. Results In total, 475 male patients and 621 female patients were included in this study. At baseline, male patients had higher values for blood pressure, serum creatinine, urine protein and serum uric acid, as well as lower levels of eGFR. Further analysis indicated that tubular atrophy/interstitial fibrosis (T) lesions and vascular lesions were more frequent in male patients. During the follow-up period of 40.9 +/- 24.2 months,kidney survival rates of male IgAN patients were remarkably lower than those of female patients. Using multivariate Cox regression analysis, male gender was identified as an independent risk factor for poor outcomes (beta = 0.384, Wald = 4.290, Exp (beta) = 1.47,p = 0.038), including hypertension, low eGFR, IgM deposition, arteriosclerosis lesions and T1-T2 lesions. However, male and female patients were characterized by different risk factors. Conclusion Male patients presented with more severe clinical and pathological changes than female patients. Renal survival rates of male patients were remarkably lower than those of female patients, and male gender was identified as an independent risk factor for poor outcomes.