SCREENING OF CHRONIC KIDNEY DISEASE IN NON-NEPHROLOGY OUTPATIENTS REVEALS POOR DIAGNOSTICS AND INADEQUATE THERAPY

Although novel treatments in chronic kidney disease (CKD) are effective in reducing the risk of its progression, CKD is often unrecognized and untreated. Effective screening programs are thus vital to combat the CKD epidemic. However, the optimal screening settings have not been yet defined.

This is a cross-sectional study (NCT07153432) performed between February and May 2025 in a large tertiary European center. The aim was to explore CKD prevalence in the population of patients followed at non-nephrology outpatient departments (hepato-gastroenterology, diabeto-endocrinology, cardiology) and to assess the penetration of prescription of nephroprotective drugs in CKD patients. The screening procedure consisted of estimated glomerular filtration rate (eGFR; estimated by the 2021 CKD-EPI equation) and urine albumin to creatinine ratio (uACR). The main inclusion criterion was increased risk of CKD per local guidelines defined as presence of 1 of the following conditions: diabetes mellitus, atherosclerotic disease, arterial hypertension, hearth failure or age over 50. Kidney transplant recipients were excluded.

A total of 2903 patients were evaluated for eGFR and uACR. Overall, 32.5% of patients met the KDIGO criteria for CKD; 21.7% presented with decreased eGFR while 18.3% presented with increased uACR. Prevalence of CKD was comparable among men and women (33.8% vs. 31%, respectively). When categorized into risk categories according to KDIGO, 18.8% were in the moderately increased risk, 8% in the high-risk and 5.7% in the very high-risk categories. Out of the 1071 cases with abnormal results, only 668 (62.4%) had previously recognized CKD. Thus, an additional 403 (33.8%) previously unrecognized CKD cases were revealed by the screening procedure, which equates to 5.2 patients needed to be screened in order to detect one new case of CKD. The conditions most strongly associated with CKD were age > 60 years (OR = 2.3), Charlson comorbidity index > 4 (OR = 2.7), previous non-renal transplant (OR = 1.8), heart failure (OR = 1.8), atrial fibrillation (OR = 1.8), and presence of atherosclerotic cardiovascular disease (OR = 1.9). Of the CKD patients fulfilling indication criteria, 78.6% were being prescribed RAAS inhibitors, but only 42% SGLT-2 inhibitors, 42.6% GLP-1 receptor agonists, and 6.7% non-steroidal mineralocorticoid receptor antagonists. This shows a significant room for patient care improvement despite the tertiary care center setting. When previously published eGFR slope data of SGLT-2 inhibitor treatment are considered (Fernández-Fernandez et al. Clin Kidney J. 2023 Jun 16;16(8):1187-1198.), a hypothetical scenario in which an SGLT-2 inhibitor would be given to all eligible patients shows that up to 6924 cumulative years of delay to kidney failure could be achieved, up to 15.3 years per newly treated patient on average.

Patients followed at tertiary care centers are excellent candidates for CKD screening programs, which are cost-effective, yield high rates of previously unrecognized patients with CKD, and thus can have a profound impact on public health.