Abstract
INTRODUCTION: Kidney Disease: Improving Global Outcomes (KDIGO) 2012 guidelines classify chronic kidney disease (CKD) risk or prognosis using estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR). We assessed patient characteristics and outcomes according to the KDIGO classification, using data from DISCOVER CKD (NCT04034992). METHODS: Data were extracted from the US integrated Limited Claims and Electronic Health Record Dataset and TriNetX databases, and the UK Clinical Practice Research Datalink linked to Hospital Episode Statistics and Office for National Statistics databases. Eligible patients were aged ≥18 years with CKD, and identified by 2 consecutive eGFR measures (5 to <75 ml/min/1.73 m(2); ≥90 days apart [maximum 730]) from January 2008. Index date was the second eGFR measurement; patients were categorized using the UACR measure closest to the index. Outcomes included patient characteristics, eGFR or UACR measurement frequency, and clinical outcomes per baseline KDIGO classification. RESULTS: Across databases, only 8.6% of patients with 2 eGFR measures had ≥1 UACR measures. Among 123,807 eligible patients, prevalence of heart failure, hypertension, and type 2 diabetes increased with increasing albuminuria. Incidence rates of mortality and adverse cardiovascular and renal outcomes increased with declining baseline eGFR, and particularly with increasing albuminuria. Median number of eGFR and UACR tests per year post-index ranged from 1.6 to 2.5 and 0.5 to 0.6, respectively, across databases; there was no clear increase in UACR testing frequency following the KDIGO 2012 guidelines. CONCLUSION: Albuminuria monitoring is critical for optimal risk stratification in CKD, and our findings highlight an imperative for more regular UACR testing in clinical practice.