Association between low renal function and tooth loss over 5 years.

OBJECTIVES: This longitudinal study evaluated the relationship between low renal function and tooth loss in elderly subjects. MATERIAL AND METHODS: Subjects comprised 406 female subjects (55-74 years old) who agreed to participate in a baseline examination and a follow-up examination after 5 years. Serum cystatin C levels were used to assess renal function. Multiple logistic regression analysis was used to evaluate the relationship between tooth loss and change in serum cystatin C levels over 5 years. Tooth loss over 5 years (0: no, 1: yes) was used as the dependent variable. Seven variables were used as independent variables, including change in serum cystatin C levels over 5 years. RESULTS: Results of multiple logistic regression analysis showed that cystatin C change over 5 years, age, number of remaining teeth at baseline, number of sites with >/=4 mm clinical attachment level at baseline and serum 25-hydroxyvitamin D levels at baseline were significantly associated with tooth loss. The odds ratio for tooth loss with cystatin C change over 5 years was 7.70 (p=0.029). CONCLUSION: This study indicates a relationship between serum cystatin C levels and number of missing teeth, and thus suggests that low renal function is associated with tooth loss.