The Impact of Smoking on Inflammation Indices: a Cross-Sectional Study

Abstract

We aim to investigate the association between smoking and systemic inflammation index (SII), the platelet-to-lymphocyte ratio (PLR), and the neutrophil-to- lymphocyte ratio (NLR) which are derivated from whole blood count. A total of 188 individuals who admitted to organ transplant outpatient polyclinics as donor candidates were included in this retrospective cross-sectional study. Donor candidates were divided into two groups; smokers and non-smokers. SII, PLR, and NLR were formulated from their hemogram during the preparation for donation. Serum C-reactive protein, uric acid, and creatinine levels were also compared between the two groups. P<0.05 was assumed as statistically significant. Seventy-five of 188 individuals (39.9%) were smokers. Smokers were older compared to nonsmokers and the mean smoking longevity was 21.14±12.92 years. SII, NLR, PLR, and CRP levels were higher in the smokers (p=0.020, p=<0.001, p=<0.001, and p=0.038, respectively). Smoking longevity had an impact on SII, PLR, NLR, and CRP (all p<0.001). Serum creatinine (and estimated glomerular filtration rate) had correlated with smoking and regression analysis indicated smoking was associated with high levels of serum creatinine (r=0.323, p<0.001, and r2=104). Smoking was a predictor for high levels of uric acid (p<0.001, r2=0.093). Smoking is associated with an increased inflammation status driven by changes in the immune response. The basic inflammation indices SII, NLR, and PLR, which can be derivated from whole blood count, and additionally CRP may be useful in the assessment of the inflammation status of smokers.