Potential Association of Body Constitution with the Prognosis of IgA Nephropathy: A Long-Time Follow-Up of 203 Cases in China

OBJECTIVE: This study investigated the association between body constitution (BC) and the prognosis of IgA nephropathy. METHODS: We analyzed 203 biopsy-diagnosed IgA nephropathy patients, who were followed up for (63.9±16.2) months. The participants' BC statuses were evaluated with the Constitution in Chinese Medicine Questionnaire; the relationships between clinical parameters and renal outcomes were analyzed by Cox regression. RESULTS: Patients were classified into chronic kidney disease stages with 43.4% in stage 1, 27.1% in stage 2, 26.1% in stage 3, 3.5% in stage 4, and none in stage 5. Qi-deficiency BC type was the most common BC type in IgA nephropathy patients. In univariate analysis, proteinuria of more than 1g/d, hypertension, renal impairment (estimated glomerular filtration rate <60 mL/min), hypoproteinemia, hyperuricemia, Yang-deficiency BC, and blood-stasis BC were associated with poor prognosis. Multivariate analysis identified that hypertension (hazard ratios (HR) 3.5, P=0.009), renal impairment (HR 5.8, P<0.001), Yang-deficiency BC (HR 2.3, P=0.041), and blood-stasis BC (HR 2.5, P=0.017) were independent predictors of unfavorable renal outcomes. CONCLUSIONS: Most patients of IgA nephropathy were biopsied at an early stage. Yang-deficiency BC and blood-stasis BC at biopsy were most closely associated with the worse prognosis of IgA nephropathy along with hypertension and renal impairment.