Quitting smoking after a cancer diagnosis is associated with high-risk neutrophil-to-lymphocyte ratio among tobacco use-related cancer survivors

Quitting smoking could potentially minimize the risk of a high neutrophil-to-lymphocyte ratio (NLR) among tobacco use-related (TUR) cancer survivors. A total of 1263 TUR cancer survivors aged 20 to 85 years old were investigated using data from the National Health and Nutritional Examination Survey 1999–2018. The primary outcome was the NLR, which was defined as having two levels: high-risk (≥ 3) and low-risk (< 3). The association between smoking cessation time and a high-risk NLR level was analyzed using weighted logistic regression models. Overall, the current smoking rate of TUR cancer survivors was found to be 21.7%. Older age (75 years above), gender and respiratory-related cancers are covariables associated with high risk of NLR levels for individual who identified as Non-Hispanic White (NHW). Non-Hispanic Black (NHB) (n = 27) who quit smoking after a cancer diagnosis were associated with the highest risk of a high NLR (OR 4.83, 95% CI 1.40–16.61, p = 0.01) compared to NHB nonsmokers (n = 139). These findings suggest that the risk of a high NLR level is strongly associated with the time of smoking cessation in NHB TUR cancer survivors. As a result, NHB TUR cancer survivors should quit smoking as soon as possible because the benefits of quitting smoking were observed over the 5 year period following smoking cessation.