Elevated neutrophil-to-lymphocyte ratio but not platelet-to-lymphocyte ratio is associated with generalized aggressive periodontitis in a Chinese population.

<bold>Background: </bold>Host inflammatory mediators are associated with tissue destruction in patients suffering from generalized aggressive periodontitis (GAgP). However, the correlations between neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) with GAgP remain unknown.<bold>Methods: </bold>Periodontal clinical parameters, including probing depth (PD), bleeding index (BI) and attachment loss (AL) were collected from patients with GAgP and healthy controls. Complete blood cells analyses were obtained; further, NLR and PLR were calculated using neutrophil, platelet, and lymphocyte counts. Smooth curve fitting and segmented regression models were used to analyze the roles and predictive value of NLR with GAgP.<bold>Results: </bold>In total, 505 participants from a Chinese population were recruited, including 133 healthy controls and 372 patients with GAgP. Periodontal clinical parameters, NLR, and neutrophil counts were significantly higher in patients with GAgP than the control group. Moreover, NLR was positively correlated with the risk and clinical parameters of GAgP. When NLR < 3, the risk of GAgP increased by 20.6% for each 0.1 increase in NLR, reaching saturation when NLR > 3. An increase in NLR equivalent to 1 was associated with an increase in PD, BI, and AL by 0.41 mm, 0.26, and 0.57 mm, respectively. Notably, PLR did not show obvious correlations with GAgP.<bold>Conclusions: </bold>NLR but not PLR may be a potential marker to identify GAgP in healthy individuals, particularly in a Chinese population. [ABSTRACT FROM AUTHOR]