Evaluation of serum neutrophil gelatinase‐associated lipocalin in older patients with chronic kidney disease

OBJECTIVE: Chronic kidney disease (CKD) is a major health‐care burden all over the world, and aging is an important risk factor for end‐stage renal disease (ESRD). Neutrophil gelatinase‐associated lipocalin (NGAL) has been confirmed as a novel marker for early diagnosis of acute kidney injury. Other studies have found that NGAL takes part in the mechanisms of CKD progression. The aim of this study was to evaluate the expression of serum NGAL in CKD, particularly in elderly patients who rapidly progressed to end‐stage renal failure. METHODS: Serum NGAL, cystatin C, creatinine, urea, and other factors were evaluated in a cohort of 160 CKD patients (mean age 75.29 ± 12.08 years) with various etiologies. RESULTS: Serum NGAL was closely related to cystatin C, creatinine, urea, and estimated glomerular filtration rate (eGFR). Special correlations between NGAL and, respectively, anemia and hypoalbuminemia were also found. The cutoff value of NGAL was calculated from Stage 2 to Stage 5. Receiver–operator curve analysis showed good area under the curve (>0.8) and high sensitivity (> 70%) on the cutoff value of NGAL. The NGAL levels increased progressively with the increasing of 2‐ and 5‐year risk of ESRD using the Kidney Failure Risk Equations (KFRE). CONCLUSION: In elderly patients with CKD, serum NGAL reflects renal impairment and presents a strong and independent risk marker for progression of ESRD.