Plasma Neutrophil Gelatinase-Associated Lipocalin and Kidney Function Decline and Kidney Disease-Related Clinical Events in Older Women

<b><i>Background:</i></b> It is still unclear whether serum neutrophil gelatinase-associated lipocalin (NGAL), a biomarker of renal tubular injury, is a prognostic marker for the progression of chronic kidney disease (CKD) in the general population. <b><i>Methods:</i></b> A prospective-cohort study of 1,245 women aged ≥70 from the general population. Associations between plasma NGAL and change in 5-year estimated glomerular filtration rate (eGFR), rapid renal decline and 10-year risk of acute or chronic renal disease-related hospitalisations and/or mortality were examined. <b><i>Results:</i></b> Compared to women with above-median plasma NGAL of 76.5 ng/l, women with below-median plasma NGAL had a 9.3% reduction in eGFR over a 5-year period. Among women with above-median plasma NGAL, there was over a 1.7-fold increased risk of rapid renal decline (eGFR decline of >3 ml/min/year) (adjusted odds ratio 1.76, 95% CI 1.003, 3.102, p = 0.049). Compared to women with baseline eGFR of <60 ml/min/1.73 m², women with above-median plasma NGAL experienced over a 2.5-fold increased risk of renal disease events at 10 years (hazard ratio 2.55, 95% CI 1.13, 5.78, p = 0.025) after adjustment of age, hypertension and diabetes. Addition of plasma NGAL in participants with eGFR of <60 ml/min/1.73 m² significantly improved the accuracy in predicting the 10-year risk of renal disease events (adjusted area-under-curve receiver operator characteristics without and with NGAL 0.64 and 0.71, respectively; p = 0.027) and reclassified 13% of women who experienced renal disease events into the higher risk categories (p = 0.03). <b><i>Conclusion:</i></b> Plasma NGAL is of modest clinical utility in predicting the renal function decline and risk of renal disease-related clinical events, particularly those with mild to moderate CKD.