From the Guidelines
The neutrophil to lymphocyte ratio (NLR) is a significant prognostic marker for poor outcomes in various conditions, including cancer, and should be considered in clinical practice as a simple and inexpensive indicator of systemic inflammation. The NLR is calculated by dividing the absolute neutrophil count by the absolute lymphocyte count from a complete blood count, with values above 3 often considered elevated 1. A high NLR has been associated with reduced quality of life and survival in patients with advanced disease, as it reflects an upregulated immune response and systemic inflammation 1.
Key Points to Consider
- Elevated NLR values are associated with worse prognosis in various conditions, including cancer 1
- The ratio increases during acute stress or inflammation as neutrophils rise while lymphocytes decrease
- Clinicians should interpret NLR values in context with other clinical findings and laboratory tests
- Serial measurements of NLR may provide more valuable information than a single reading, especially when monitoring treatment response or disease progression
Clinical Implications
The NLR can be used as a prognostic marker to identify patients at high risk of poor outcomes, allowing for early intervention and personalized treatment plans. For example, in patients with cancer, a high NLR has been associated with poor cancer outcomes, including reduced survival and quality of life 1. By monitoring NLR values, clinicians can assess the effectiveness of treatment and make adjustments as needed to improve patient outcomes.
Limitations and Considerations
While the NLR is a useful prognostic marker, it should be interpreted in context with other clinical findings and laboratory tests, as it can be affected by medications, acute infections, and chronic conditions 1. Additionally, serial measurements of NLR may provide more valuable information than a single reading, especially when monitoring treatment response or disease progression.
From the Research
Significance of Neutrophil to Lymphocyte Ratio
The Neutrophil to Lymphocyte Ratio (NLR) is a significant marker of systemic inflammation that has been widely used to predict mortality and morbidity in various medical conditions. Some key points about NLR include:
- NLR is an easy-to-measure laboratory marker that reflects the dynamic relationship between innate and adaptive cellular immune responses during illness and various pathological states 2.
- An elevated NLR is associated with poor survival and increased morbidity in cancer and cardiovascular disease 3.
- NLR is influenced by many conditions, including age, chronic disease, medication, and stress 2.
- A normal range of NLR is between 1-2, while values higher than 3.0 and below 0.7 in adults are considered pathological 2.
Clinical Applications of NLR
NLR has various clinical applications, including:
- Predicting mortality in medical inpatients with multiple chronic conditions 3.
- Serving as a reliable and cheap marker of ongoing cancer-related inflammation and a valid indicator of prognosis of solid tumors 2.
- Diagnosing and stratifying systemic infection, sepsis, and bacteremia 2, 4.
- Predicting the outcome of patients with ST-elevation myocardial infarction (STEMI) 5.
- Identifying individuals at risk of mortality in the general population 6.
Interpretation of NLR Values
The interpretation of NLR values is crucial in clinical practice. Some key points include:
- NLR values above 3.0 are associated with increased mortality and morbidity in various medical conditions 3, 2, 5.
- NLR values in the grey zone between 2.3-3.0 may serve as an early warning of pathological states or processes 2.
- Dynamic changes in NLR values can precede clinical states and warn clinicians about ongoing pathological processes 2, 4.