Hospitalized patients with reduced kidney function on admission who are discharged with apparently normal kidney function have increased risks for end-stage kidney disease (ESKD) and death, a new study finds.
Among 40,558 adults without pre-existing chronic kidney disease or kidney transplant, 6226 (15%) had an estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m2 on admission. They did not meet time-dependent KDIGO criteria for acute kidney injury throughout hospitalization and were later discharged with normal kidney function exceeding 60 mL/min/1.73 m2.
Patients with decreased eGFR on presentation had a significant 18% increased risk of dying within 1 year compared with those who presented with normal kidney function, Orly Efros, MD, MHA, National Hemophilia Center and Thrombosis & Hemostasis Institute, Sheba Medical Center in Ramat Gan, Israel, and colleagues reported in JAMA Network Open. This group with a low-to-normal kidney function trajectory also had a significant 3.7-fold increased risk of progressing to ESKD within 10 years.
Patients who presented to the hospital with an eGFR of 0 to 45 mL/min/1.73 m2 fared the worst. They had significant 1.4- and 3.5-fold increased risks for early death and ESKD, respectively. Analyses using serum creatinine alone supported these trends.
The investigators adjusted their analyses for age, sex, hypertension, diabetes, ischemic heart disease, heart failure, cancer, atrial fibrillation, and chronic obstructive pulmonary disease. Many of these factors disproportionally affected the low-to-normal kidney function group.
When normal kidney function was re-defined as an eGFR of more than 90 mL/min/1.73 m2, no excess risks were found. The investigators also could not completely rule out the potential influence of muscle loss over the hospitalization.
“A possible explanation for our findings is that an observed decrease in kidney function during hospitalization might reveal an existing decreased kidney reserve, unmasked by the stress of acute illness,” Dr Efros’ team stated. They recommended that such patients receive outpatient medical observation after discharge.
Efros O, Beckerman P, Basson AA, et al. Fluctuations in serum creatinine levels during hospitalization and long-term end-stage kidney disease and mortality. JAMA Netw Open. Published online August 1, 2023. doi:10.1001/jamanetworkopen.2023.26996