Serum Rheumatoid Factor as Risk Predictor for Tooth Loss

Objectives: The purpose of this study was to evaluate the relationship between tooth loss over a 10-year period and serum rheumatoid factor (RF) level in community-dwelling elderly women. Methods: We selected 206 women aged 70 years with ≥14 teeth at baseline. Among them, 116 subjects were followed up for 10-year examination. We defined a serum RF >15 U/ml as RF(+), and compared oral health status, oral health behavior at baseline and the number of missing teeth during 10 years between RF >15 U/ml and RF ≤15 U/ml at baseline using Student's t-test, chi-squared test, and Mann-Whiteny U test when applicable. Furthermore, multiple linear regression analysis was used to evaluate the relationship between the number of missing teeth during 10 years and serum RF level. The number of missing teeth during 10 years was selected as the dependent variable. Serum RF level was selected as independent variable including other six items. Results: The subjects with serum RF level >15 U/ml had significantly higher number of missing teeth during 10 years compared with the subjects with serum RF level ≤15 U/ml at baseline. The number of missing teeth were 6.2±6.4 and 2.6±2.8 (p=0.024), respectively. A significant relationship was identified between the number of missing teeth during 10 years and serum RF level at baseline according to multiple linear regression analysis adjusted for six variables. The beta of serum RF level for the number of missing teeth was 0.48 (p<0.001). Conclusion: This study shows a clear relationship between serum RF level and the number of missing teeth during 10 years. These findings suggest that high RF level contribute to tooth loss in elderly women.