Prevalence of Undertreated CKD among Hospital Inpatients: A Prospective Cross-Sectional Study

BACKGROUND: CKD affects 14% of adults in Australia and is frequently under-recognised or diagnosed in late stages when opportunities to prevent progression to kidney failure have been missed. Existing early identification programs target primary care or specific high-risk populations. Hospitalisation may present an opportunity to identify undertreated CKD. We hypothesise that there is a high prevalence of undertreated stage 3b-5 CKD among patients admitted to teaching hospitals in Sydney, Australia. METHODS: We prospectively identified all adult patients with an eGFR < 45ml/min/1.73m2 admitted to hospital under a non-nephrology service, in six metropolitan hospitals from two health districts of Sydney, Australia, between March 2024-Feb 2025 inclusive. To identify those mostly likely to benefit from guideline directed medical therapy (GDMT) for CKD, we excluded those >80 years of age, pregnant, diagnosed with dementia, nursing home residents, who had a life-expectancy less than 2 years, or who had acute kidney injury. We extracted demographic, co-morbidity and medication data from the electronic medical record. RESULTS: Among 77,447 patients, 11,243 (14.5%) had an eGFR < 45ml/min/1.73m2 on admission. After exclusions, 956 patients (1.2%) were included in the study. Median age was 75 years (IQR: 70,78), and participants had multiple co-morbidities including hypertension (78.1%), diabetes (40.7%), obesity (46.8%), coronary artery disease (34.6%) and heart failure (22.1%). CKD was documented in 24.2% and 5.8% had a urine albumin:creatinine (UACR) result available. Medications on admission included SGLT2 inhibitors (18.5%), renin-angiotensin blockers (52.1%), and statins (63.2%). CONCLUSIONS: Hospital admission represents a unique opportunity to identify undiagnosed and/or undertreated patients with mid to late-stage CKD. Interventions designed to detect and better manage this population warrant further investigation.