REFERENCE VALUES OF NEUTROPHIL LYMPHOCYTE RATIO AND PLATELET LYMPHOCYTE RATIO IN HEALTHY ADULTS IN A TERTIARY CARE CENTER IN NORTH INDIA

Background: Neutrophil Lymphocyte Ratio (NLR) and Platelet Lymphocyte Ratio (PLR) have been suggested as easily measurable and less invasive marker with predictive and prognostic implications in various inflammatory and ischemic conditions. The studies showing the role of NLR and PLR as a predictive prognostic factor in several inflammatory and ischemic conditions have their cut-off value based on the median, higher quartile, or values determined using receiver-operating curves. Also, their values have been postulated to have geographical, racial, gender, and age differences. A standardized reference value of these attributes is therefore needed to put the results of previous studies into a context that allows for proper interpretation of their potential clinical value.

Objectives: To establish the reference values for Neutrophil-lymphocyte ratio (NLR) and Platelet-lymphocyte ratio (PLR) in healthy adults in a tertiary care center in North India.

Methods: 500 apparently healthy volunteers aged 18-60 years were enrolled for the study and their blood samples were analyzed by an automated counter (MinDr.ay Bc-6800) to get complete hemogram values. Neutrophil Lymphocyte Ratio (NLR) was calculated by dividing absolute neutrophil count by absolute lymphocyte count, likewise, Platelet Lymphocyte ratio (PLR) was calculated by dividing platelet count by absolute lymphocyte count.

Results: The mean NLR and PLR in our study were 1.9±0.6 and 91.77±26.95, respectively. The mean NLR was 1.88±0.61 in males and 1.93±0.59 in females (P-value = 0.373). The mean PLR was 91.55±27.49 in males and 92.08±26.24 in females (P-value = 0.834). The mean NLR for different age groups was 1.87±0.60, 1.93±0.62, and 1.90±0.58 in 18-30, 31-45, and 46-60 years respectively (P-value0.584). The mean PLR was 92.53±27.98, 90.54±26.53, and 92.61±25.75 in 18-30, 31-45, and 46-60 years age groups respectively (P-value = 0.735).

Conclusion: We propose a normal NLR and PLR to be 1.9±0.6 and 91.77±26.95 respectively in our population of North India with no significant difference between males and females. Also, we conclude that NLR and PLR do not differ with age. But more studies with a larger number are required to delineate the difference of NLR and PLR as per sex and age-group is concerned.