Differences in chronic kidney disease management based on identification and diagnosis in a population-based observational study.

Abstract

Background: Chronic kidney disease (CKD) affects 6-10% of adults and often remains undiagnosed until advanced stages, leading to inadequate management. This study compared diagnosed, proxy-diagnosed, and undiagnosed CKD patients regarding prevalence, clinical assessment, nephroprotective treatment, healthcare utilization, and mortality.

Methods: This retrospective observational study analyzed Region Halland's healthcare data for adults meeting KDIGO CKD-confirmed criteria for the year 2019. Patients were categorized as diagnosed CKD (ICD-coded), proxy-diagnosed CKD (CKD-related diagnoses), or undiagnosed CKD (meeting CKD criteria without an ICD CKD diagnosis).

Results: Of 20,488 CKD patients, 21% had diagnosed CKD, 18% proxy-diagnosed CKD, and 61% undiagnosed CKD. Mean ages were 76.4, 62.4, and 81.8 years, respectively (p < 0.001). Blood pressure follow-up was carried out in diagnosed CKD (88%) versus 67% and 80% in the proxy-diagnosed and undiagnosed groups. eGFR was tested in 66% overall (73% diagnosed, 53% proxy-diagnosed, 66% undiagnosed), while urine albumin-to-creatinine ratio (UACR) testing was performed in 27% overall (50%, 20%, and 21%, respectively). Renin-angiotensin system inhibitors were prescribed to 45% overall (51%, 28%, and 47%, respectively). The adjusted hospitalization risk was 2.71 (CI: 2.59-2.84) in diagnosed CKD and 1.38 (CI: 1.31-1.46) in proxy-diagnosed CKD. Adjusted all-cause mortality hazard ratios were 2.22 (CI: 1.95-2.52) and 1.31 (CI: 1.08-1.60), respectively. Stratified sensitivity analyses by CKD stage confirmed these associations, though the strength varied.

Conclusions: Patients with complex comorbidities, more advanced CKD, and frequent hospitalizations are more likely to be diagnosed with CKD and receive better follow-up care. Proxy-diagnosed CKD was common and associated with suboptimal management. These findings emphasize the need for consistent and accurate CKD identification to improve outcomes and optimize care.