Investigation of periodontitis, halitosis, xerostomia, and hematological characteristics of patients with osteoarthritis and rheumatoid arthritis and identification of new biomarkers

Abstract

Abstract Rheumatoid arthritis (RA) and osteoarthritis (OA) are two different types of arthritis. These two diseases share similar clinical characteristics; however, each has a different etiology and requires different treatment. Thus, the accurate diagnosis and development of reliable biomarkers for diagnosing these two diseases is important. This study investigated and compared the distribution of salivary flow rate, xerostomia, halitosis, and periodontitis in patients with RA and OA to clarify the differences from healthy controls. In addition, we investigated the hematological characteristics of the patients, the factors that distinguished patients with RA from those with OA, and the main factors that differentiated between seronegative RA (snRA) and seropositive RA (spRA) patients. A total of 161 participants (mean age: 52.52 ± 14.57 years, 32 males and 129 females) were enrolled in this study and categorized as: normal (n = 33), OA (n = 31), and RA (n = 97). Patients with RA were divided into the following two subtypes: snRA (n = 18) and spRA (n = 79). Demographics, oral health, and hematological characteristics of these patients were compared. The prevalence of periodontal diseases was significantly higher in patients with OA (100%) and RA (92.8%) than in healthy controls (0.0%). Xerostomia occurred more frequently in patients with RA (84.5%) than in patients with OA (3.2%) and healthy controls (0.0%) (all p < 0.001). ROC analysis revealed that periodontal disease was a very strong predictor in the diagnosis of OA compared to healthy controls, with an AUC value of 1.00 (p < 0.001). Additionally, halitosis (AUC = 0.746, 95% CI: 0.621–0.871, p < 0.001) and female sex (AUC = 0.663, 95% CI: 0.529–0.797, p < 0.05) were also significant predictors of OA. The strongest predictors of RA diagnosis compared to healthy controls were periodontal diseases (AUC = 0.964), followed by xerostomia (AUC = 0.923), age (AUC = 0.923), female sex (AUC = 0.660), and halitosis (AUC = 0.615) (all p < 0.05). Significant hematological predictors of RA were anti-CCP Ab (AUC = 0.808), and RF (AUC = 0.746) (all p < 0.05). When diagnosing spRA compared to snRA, anti-CCP Ab (AUC = 1.000, p < 0.001) and RF (AUC = 0.910, 95%CI: 0.854–0.967, p < 0.001) had outstanding predictive performances. Periodontal diseases were present in majority of patients with OA and RA, and were not used as a distinguishing factor between these two diseases. However, xerostomia was overwhelmingly prevalent in patients with RA and had a predictive performance comparable to that of anti-CCP Ab in predicting RA. Therefore, clinicians and researchers should carefully examine the oral status of patients with OA and RA and consider it as a predictor.