Attribute-based medicine for IgA nephropathy: risk factor constellations influence kidney prognosis

Attribute-based medicine emphasizes tailoring care to patient-specific characteristics. Immunoglobulin A nephropathy (IgAN), a heterogeneous glomerular disease, presents varying risks across subgroups. We hypothesized that an attribute-based medicine approach could identify residual risk factors and inform personalized strategies.

We analysed data from 996 patients from the Japanese Nationwide Retrospective Cohort Study in IgAN. The primary outcome was kidney replacement therapy initiation or a 1.5-fold increase in serum creatinine. Six pre-specified attributes were assessed: age, sex, body mass index (BMI), chronic kidney disease (CKD) stage, urinary protein excretion (U-Prot) and urine occult blood (U-OB). Cox regression and Kaplan-Meier analyses were performed to evaluate interactions between attributes and risk factors.

Poor kidney prognosis was associated with lower estimated glomerular filtration rate (eGFR) [per 10 mL/min/1.73 m² increase, hazard ratio (HR) = 0.87], higher U-Prot (log-transformed HR = 4.54) and hyperuricaemia (HR = 1.64), while oral corticosteroids (HR = 0.60) and tonsillectomy (HR = 0.44) were protective factors. Significant interactions included the following: hyperuricaemia with BMI <22 kg/m²; hypertension with female sex; eGFR and age with CKD stage; U-Prot with age, eGFR and corticosteroid use; and U-Prot with U-OB. Prognostic effects of age and eGFR were reversed for CKD stage 3 compared with stages 1-2. U-Prot was the most consistent predictor of poor prognosis, especially in patients with U-OB ≤2+. Corticosteroids improved outcomes in patients with U-Prot ≥1 g/day, while tonsillectomy was effective in those with U-OB ≥3+.

Attribute-based analysis revealed critical risk modifiers and supported stratified treatment strategies for IgAN. These findings underscore the potential of attribute-based medicine in guiding personalized care for patients with IgAN.