Evidence-practice gaps in chronic kidney disease management among patients taking antidiabetic or antihypertensive medications: a nationwide analysis of Japanese primary care electronic health records.

BACKGROUND

The management of chronic kidney disease (CKD) in primary care remains poorly defined despite primary care physicians managing a high proportion of patients with hypertension and diabetes. This study examined CKD-related laboratory testing and anemia management patterns in Japanese primary care settings.

METHODS

Using the Japan Medical Data Survey (JAMDAS) database, we analyzed electronic health records from Japanese primary care clinics. We included patients aged ≥ 18 years who received antihypertensive or antidiabetic medications at least twice in 2024 and visited clinics quarterly, excluding those who received kidney replacement therapy.

RESULTS

Among 859,044 eligible patients (mean age: 70.3 years; men: 48.9%), estimated glomerular filtration rate, dipstick proteinuria, serum potassium, and hemoglobin were measured in 76.2%, 11.2%, 62.9%, and 69.6% of patients, respectively. Proteinuria testing declined with increasing age. Of 604,936 patients who underwent any anemia-related laboratory testing, only 5.1%, 0.4%, and 15.1% had their serum ferritin, transferrin saturation, and serum iron measured, respectively. Among 5219 patients with coded renal anemia, 73.9% received erythropoiesis-stimulating agents (ESAs) or hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs). Notably, 58.6% of 553 patients with a renal anemia diagnosis and hemoglobin levels ≥ 13 g/dL were treated with ESAs or HIF-PHIs.

CONCLUSION

Evidence-practice gaps in CKD management were identified in Japanese primary care settings, including limited proteinuria testing and raising hemoglobin levels above guideline-recommended limits, despite inadequate evaluation of iron parameters. These findings indicate that systematic quality improvement initiatives are needed to improve CKD management in primary care.