Clinicopathological characteristics and risk factors in elderly patients with biopsy-proven IgA nephropathy

Abstract

Background Immunoglobulin A nephropathy (IgAN) has been well studied among young people, but few data on clinicopathological characteristics, treatment response and outcomes for elderly IgAN patients are available. Methods A cohort study of elderly IgAN patients was performed. The combined endpoints of renal outcome were a 50% decline in eGFR compared with the time of renal biopsy, end-stage kidney disease and/or death. Risk factors associated with poor renal outcomes were then determined. The benefits of immunosuppressant therapies were also evaluated by Kaplan-Meier survival curve analysis. Results This study ultimately included 126 elderly patients with IgAN. Comparison between the endpoint and non-endpoint groups indicated that patients with poor outcomes had more severe clinical features, such as worse kidney function, severe hematuria and lower albumin levels. Cox regression analysis indicated that age (HR 1.15, 95% CI 1.02–1.29, p = 0.021), male gender (HR 9.71, 95% CI 1.00–97.56, p = 0.050), and urine red blood cells (HR 1.003, 95% CI 1.000–1.006, p = 0.029) were independent risk factors for poor renal outcome in elderly IgAN patients. To explore possible reasons accounting for the predictive value of age and sex, patients were divided into two groups based on these two variables. Patients in the geriatric group had lower serum albumin, estimated glomerular filtration rate, hemoglobin and aspartate aminotransferase levels than those in the quinquagenarian group. Male patients tended to have higher hemoglobin, higher alanine aminotransferase, and lower triglycerides and cholesterol levels than female patients. To investigate different treatment responses, patients were classified into two groups depending on treatment strategies (renin-angiotensin system inhibitors and immunosuppressive therapy), and the survival analysis indicated no significant difference in kidney outcome between the two groups ( p > 0.05). This result still holds after adjusting for age, sex, eGFR, hematuria, and proteinuria. Conclusion Advanced age, male, and hematuria might be independently associated with poor kidney outcomes in elderly patients with IgAN. Immunosuppressive therapy might confer no overall benefit to older IgAN patients.

Gender-related differences in IgA nephropathy; an eleven-year experience according to revised Oxford classification

“…During their follow-up, renal survival rates of male IgAN patients were significantly lower than female patients (17). Consistently, other studies found that being male was associated with greater levels of serum creatinine and a worse outcome (17,18). An analysis by Riispere et al on 73 biopsy-proven IgAN cases (62% males and 38% females) held the same view that IgAN progresses more rapidly in male than in female patients through faster glomerular filtration rate declines.…”

“…Lv et al demonstrated, proteinuria of more than 1 g/d connected to poor prognosis in patients with an average of 6.1 years (23). Contrary to these results, Sevillano et al in a cohort of 151 patients ≥65 years old, and Tan et al on 126 patients with a mean age of 57.12 ± 6.24 years, reported proteinuria was not significantly associated with poor outcomes (16,18). We suggest that the disparity between these studies can be due to several variables, including the patient population, the duration of follow-up, age, behavioral patterns such as individual physical activity or eating habits, race, biopsy practice, and various outcome definitions.…”

Clinical Significance of Persistent Hematuria Degrees in Primary IgA Nephropathy: A Propensity Score-Matched Analysis of a 10-Year Follow-Up Cohort

“…2). The decrease in these indicators was found to be associated with a poor prognosis in previous studies [17,18]. However, the multivariate Cox proportional hazards model showed that the crescent was not an independent risk factor.…”

Detection of N‑glycoprotein associated with IgA nephropathy in urine as a potential diagnostic biomarker using glycosylated proteomic analysis

“…IgAN accounts for ~40% of all native-kidney biopsies in Japan, 25% in Europe and 12% in the United States ( 56 , 57 ). Currently, the gold standard for the diagnosis of IgAN remains renal biopsy, which, as an invasive diagnostic method, has numerous limitations and may lead to multiple complications ( 58 , 59 ). Traditional clinicopathological indicators remain inadequate to predict the diagnosis, progression and prognosis of IgAN, such as blood pressure, albuminuria and hematuria.…”