Cardiovascular, renal and mortality risk by the KDIGO heatmap in Japan.

Background: This study aimed to assess the prognosis of people with chronic kidney disease (CKD) in Japan using the Kidney Disease: Improving Global Outcomes (KDIGO) heatmap.

Methods: The prognoses of individuals with estimated glomerular filtration rates (eGFR) <90 mL/min/1.73 m were evaluated based on the KDIGO heatmap using an electronic medical record database in Japan. The primary outcome was major adverse cardiovascular events (MACE), a composite of myocardial infarction (MI), stroke, heart failure (HF) hospitalization and in-hospital death (referred to as MACE1). Additionally, MACE2 (MI hospitalization, stroke hospitalization, HF hospitalization and in-hospital death) was examined. The secondary outcome was the renal outcome.

Results: Of the 543 606 individuals included, the mean age was 61.6 ± 15.3 years, 50.1% were male and 40.9% lacked urine protein results. The risk of MACEs increased independently with both eGFR decline and increasing proteinuria from the early KDIGO stages: hazard ratios (95% confidence interval) of MACE1 and MACE2, compared with G2A1 were 1.16 (1.12-1.20) and 1.17 (1.11-1.23), respectively, for G3aA1, and 1.17 (1.12-1.21) and 1.35 (1.28-1.43), respectively, for G2A2. This increased up to 2.83 (2.54-3.15) and 3.43 (3.00-3.93), respectively, for G5A3. Risks of renal outcomes also increased with CKD progression.

Conclusions: This study is the first to demonstrate the applicability of the KDIGO heatmap in assessing cardiovascular and renal risk in Japan. The risk increased from the early stages of CKD, indicating the importance of early diagnosis and intervention through appropriate testing.