Diagnostic modulation of subgingival proteomic biomarkers by age and smoking habits in periodontitis

Periodontitis is a chronic inflammatory disease characterized by the progressive destruction of the supporting structures of the teeth. Previous investigations have demonstrated that certain gingival crevicular fluid (GCF) proteins exhibit high diagnostic capability for detecting periodontitis. However, individual risk factors, such as age and smoking habits, may affect the reliability of these protein-based biomarkers. In this multicenter study, we analyzed GCF samples from periodontally healthy and periodontitis subjects using the proteomic technique sequential window acquisition of all theoretical mass spectra (SWATH-MS). We evaluated the diagnostic accuracy of eight proteins, both unadjusted and adjusted for age and smoking habits (years of smoking and cigarette consumption), as well as the clinical variables alone. The results showed that age consistently improved the accuracy of all proteins in distinguishing between periodontal health and periodontitis, achieving outstanding diagnostic performance. In contrast, the impact of smoking status was lower and more protein-specific. Some biomarkers showed increased results in relation to tobacco habits, while others were less accurate when considering this risk factor. These findings highlight the influence of the patient's age and smoking status on the diagnostic accuracy of GCF proteins for detecting periodontitis.