CHICAGO – Two simple-to-calculate ratios – neutrophil lymphocyte ratio and platelet lymphocyte ratio – may be able to predict impending death in patients who have recently begun hemodialysis, based on data from 108,548 incident hemodialysis patients in the database of DaVita HealthCare Partners from 2007 to 2011.
“Neutrophil lymphocyte ratio (NLR) and platelet lymphocyte ratio (PLR), and inflammatory and nutritional indices, which are calculated from complete blood count, were identified as strong predictors of impending death ... and thus are inexpensive and immediately available markers for predicting short-term mortality,” said Yoshitsugu Obi, MD, PhD, a visiting scholar at the Harold Simmons Center for Kidney Disease Research & Epidemiology, University of California Irvine School of Medicine, Irvine, California.
Dr. Yoshitsugu Obi
The data were obtained from the database of a large dialysis organization; 108,548 patients who began hemodialysis from 2007 to 2011 were included. The range of NLR values were divided into 12 categories with ratios of less than 1.5 and greater than or equal to 6.5 as the bracketing ratios. The 10 other intervening ratios differed incrementally by 0.5. Eight SLR categories were created with the bracketing ratios being less than 5 and greater than or equal to 35. The intervening six ratios differed incrementally by 5.
The mean age of the cohort was 63 ± 15 years. Males predominated (56%), 59% of the subjects were diabetic, and 31% were African American. At baseline the median NLR and PLR were 3.64 and 13.12, respectively.
In an unadjusted regression analysis, the categories of NLR and PLR had a strong and linear relationship with all-cause mortality. In an analysis that adjusted for covariates, including demographics and comorbidities, as well as markers of malnutrition and inflammation, the association of the two ratios with all-cause mortality persisted.
Unlike previous small and inconclusive studies, the size of the present study makes robust the connection between these cell ratios and death in dialysis patients, he said. The plan now is to compare the mortality predictability of NLR and PLR with other established risk factors including albumin, phosphorus, and alkaline phosphatase.