Health Care Resource Utilization and Associated Costs Across Proteinuria and Declining Kidney Function in Patients...

Immunoglobulin A nephropathy (IgAN) is the leading cause of chronic kidney disease (CKD) and end-stage kidney disease. Few studies have assessed health care resource utilization and costs for IgAN patients with high-risk proteinuria and worsening kidney function in Europe.

Retrospective, descriptive analysis of anonymized TriNetX data (2015-2023).

Individuals from the United Kingdom, Spain, and Germany with an IgAN diagnosis recorded between 2015 and 2022.

Proteinuria and CKD stage.

Cost per visit (inpatient, outpatient, emergency visits), total cost, and mean costs per patient.

Health care resource utilization and costs were analyzed within a year post-index date and stratified by visit type, CKD stage, and proteinuria levels, with costs obtained from official and published sources. UK/Spain costs were also stratified by a composite variable considering both CKD and proteinuria levels. This was not done for Germany because available data was insufficient.

In both Spain and the United Kingdom, the average number of inpatient (Spain, 1.9-2.5; United Kingdom, 2.2-11.0) and outpatient (Spain, 13.2-38.9; United Kingdom, 5.3-13.9) visits per patient increased with increasing CKD stages 1-5; this trend was not noted for emergency visits. In comparison, the number of outpatient visits per patient with CKD stages 1-5 in the German cohort was low (2.9-4.3). The average annual composite cost per patient for all visit types was greater for patients with higher CKD stage and proteinuria levels in Spain (CKD stage G1-G2, <0.5 g/d: €487.00 vs CKD stage G5, ≥2 g/d: €26,559.44) and the United Kingdom (CKD stage G1-G2, <0.5 g/d: £432.95 vs CKD stage G5, ≥2 g/d: £36,253.80).

Electronic medical records may be subject to misclassification, incorrect coding, and documentation errors.

This study highlights the association between declining kidney function, increased proteinuria, and considerable economic burden.