Clinical and Humanistic Burden of IgAN in Adult Patients: A Global Real-World Survey.

Background: Immunoglobulin A nephropathy (IgAN) is a chronic, progressive kidney disease in which proteinuria, reduced estimated glomerular filtration rate (eGFR), pain and fatigue are common. How symptoms interact and impact 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 IgAN patients.

Methods: Data were drawn from the Adelphi IgAN Disease Specific Programme™, a cross-sectional survey of physicians and their biopsy confirmed IgAN patients in China, France, Germany, Italy, Spain, the United Kingdom, United States, and Japan, from June-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 Quality of Life, and Work Productivity and Activity Impairment questionnaires. Symptom scores were grouped by severity and patients grouped by proteinuria and eGFR. Analysis of variance, chi-squared or Fisher's exact tests were performed as appropriate and Dunn's multiple comparisons with Bonferroni adjustment for pair-wise comparisons.

Results: Overall, 1515 patients were included (mean [standard deviation] 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 than their counterparts. Physicians underestimated fatigue levels faced by patients. In order to improve QoL, more effective treatments are needed to prevent high proteinuria and preserve eGFR.