Relationship between hemoglobin and renal tubular atrophy/interstitial fibrosis in patients with IgA nephropathy / 中华肾脏病杂志

ABSTRACT

Objective@#To clarify the relationship between the hemoglobin level and renal tubular atrophy/interstitial fibrosis (T) in the Oxford stage of renal pathology in IgA nephropathy (IgAN) patients.@*Methods@#Patients diagnosed with IgAN by renal biopsy from January 1st 2010 to December 31st 2015 in Shenzhen Second People's Hospital with complete laboratory and imaging data were retrospectively analyzed. Patients were divided into anemic group and non-anemic group. The relationship between hemoglobin level and renal tubular atrophy/interstitial fibrosis was determined by logistic regression analysis. The possible curve relationship between hemoglobin and renal tubular atrophy/interstitial fibrosis was analyzed by smooth curve fitting analysis. The diagnostic value of hemoglobin for renal tubular atrophy/interstitial fibrosis was analyzed by the receiver operating curve (ROC).@*Results@#A total of 630 patients with IgAN were included in this study, 130 patients in the anemia group (20.63%) and 500 patients in the non-anemia group (79.37%). There was no statistically significant difference in age between the two groups, but the difference of the gender was statistically significant (male 35.38% vs 53.80%, χ2=10.740, P<0.001). Compared with the non-anemia group, the anemia group had a higher proportion of tubular atrophy/interstitial fibrosis (χ2=62.586, P<0.001), higher 24 h urinary protein quantification (Z=-6.082, P<0.001), and lower eGFR (t=7.126, P<0.001). Multivariate logistic regression analysis showed that increasing hemoglobin level was an independent protective factor for reducing the risk of renal tubular atrophy/interstitial fibrosis (OR=0.973, 95%CI 0.958-0.987, P<0.001). Smooth curve fitting analysis showed that there was a linear negative correlation between hemoglobin and tubular atrophy/interstitial fibrosis. The ROC curve suggested that the best threshold of hemoglobin was 120.5 g/L when renal tubular atrophy/interstitial fibrosis occurred. That was, when hemoglobin was above 120.5 g/L, the severity level of renal tubular atrophy interstitial fibrosis might be reduced.@*Conclusion@#The incidence of renal tubular atrophy/interstitial fibrosis is higher in IgAN patients with anemia, and hemoglobin>120.5 g/L may reduce the risk of tubular atrophy/interstitial fibrosis.