Clinical and Humanistic Burden of IgA Nephropathy in Adult Patients

Key Points IgA nephropathy (IgAN) exerts a significant humanistic burden on patients. Quality of life is impaired in patients with IgAN. Progression of disease in IgAN, especially proteinuria and GFR loss, are associated with the burden of disease. Background IgA nephropathy (IgAN) is a chronic, progressive kidney disease in which proteinuria, reduced eGFR, pain, and fatigue are common. How symptoms interact and affect patient quality of life (QoL) in real-world practice is poorly studied. This study investigated how patient and physician symptom perceptions differ and how proteinuria and eGFR correlate with pain, fatigue, and QoL in adult patients with IgAN. Methods Data were drawn from the Adelphi IgAN Disease Specific Program, a cross-sectional survey of physicians and their biopsy confirmed patients with IgAN in China, France, Germany, Italy, Spain, the United Kingdom, the United States, and Japan from June to October 2021. Physicians provided demographics and clinical characteristics, including pain and fatigue severity. The same patients completed a self-completion form containing questions on symptom severity, the EQ-5D-5L, Kidney Disease QoL, and Work Productivity and Activity Impairment questionnaires. Symptom scores were grouped by severity, and patients were grouped by proteinuria and eGFR. Analysis of variance, chi-squared, or Fisher exact tests were performed as appropriate and Dunn multiple comparisons with Bonferroni adjustment for pair-wise comparisons. Results Overall, 1515 patients were included (mean [SD] age: 43 [15] years, 60% [ n =903] male, 70% [ n =1020/1459] diagnosed >1 year ago). Pain was reported by 46% ( n =374) of physicians and 47% ( n =384) of patients and fatigue by 65% ( n =530) of physicians and 76% ( n =620) of patients. Both pain and fatigue increased with increased proteinuria and reduced eGFR (all P < 0.001). Finally, patients with increased proteinuria and reduced eGFR experienced worse ( P < 0.05) QoL and work productivity across all measures (except work absenteeism). Conclusions Patients with higher proteinuria and lower eGFR face higher symptom burden and reduced QoL compared to their counterparts. Physicians underestimated fatigue levels faced by patients. To improve QoL, more effective treatments are needed to prevent high proteinuria and preserve eGFR.