Neutrophil/lymphocyte ratio is correlated with levels of inflammatory markers and is significantly reduced by smoking cessation

Abstract

Previous studies have reported that the neutrophil to lymphocyte ratio (NLR) is associated with onset and prognosis of cardiovascular disease (CVD). Smoking is a major risk factor for CVD and smoking cessation significantly reduces CVD risk. However, the effects of smoking cessation on the NLR remain unknown. Among smokers visiting our smoking cessation clinics, we examined changes in the NLR and CVD biomarkers before and after smoking cessation. A total of 389 individuals (301 men and 88 women) were enrolled in the study. The median NLR was significantly reduced after successful smoking cessation (before: 1.8, interquartile range [IQR] 1.5, 2.5; after: 1.7, IQR 1.3, 2.4). In a linear regression model adjusted for sex, percent change in NLR comparing before and after smoking cessation was significantly and positively correlated with percent changes in C-reactive protein (β = 0.260), α1-antitrypsin-low density lipoprotein (β = 0.151, p < 0.05), and serum amyloid A-low density lipoprotein (β = 0.325). Our study demonstrated for the first time that smoking cessation significantly reduces the NLR in tandem with markers of inflammation and oxidative stress.

Influence of oral tobacco versus smoking on multiple sclerosis disease activity and progression

“…Although rather few patients stopped smoking post diagnosis, and the ability to assess benefits of smoking cessation was limited, our finding is in accordance with previous studies 6–8. A reduction of systemic inflammation and oxidative stress following smoking cessation may contribute to the favourable effect on disease outcomes 28–30…”

“…[6][7][8] A reduction of systemic inflammation and oxidative stress following smoking cessation may contribute to the favourable effect on disease outcomes. [28][29][30] Although we found a significant influence of current smoking on the risk of cognitive disability worsening in MS as well as a trend showing increased risk of unfavourable outcome with increasing cumulative dose of smoking, we observed no significant association in our main analysis where individuals were followed up to 15 years. Further studies are thus needed to investigate the impact of smoking on cognitive functioning in MS.…”

An Elevated Neutrophil-to-Lymphocyte Ratio Predicts Poor Prognosis in Patients with Liver Cancer after Interventional Treatments

“…However, since the lymphocyte and neutrophil counts are affected by many factors, especially infections [46,47] and drugs [48], and in a recent study, COVID-19 infection was also found to result in severe lymphopenia [49], therefore, cautions should be taken to interpret the changes of NLR in HCC patients, and additional data, particularly inflammation-related data, are needed to trace the therapeutic outcomes and to rule out other factors and diseases that may affect changes. For example, the pathogenesis of several diseases such cardiovascular diseases [50], retinal artery occlusion [51], and spinal epidural abscess [52] have been found to result in high NLR, while treatment with 25-hydroxyvitamin D 3 and smoking cessation are associated with a reduced blood NLR [53,54], suggesting when NLR is used for individual patients, it should be evaluated along with other pathological conditions to obtain more reliable prediction. Mechanisms by which high NLR are associated with poor HCC prognosis may result from the interaction between tumor and inflammatory microenvironment [55,56].…”