Association Between Low Kidney Function and Excess Weight Concerning Unfavourable Periodontal Health among Community-dwelling Older Japanese Women.

Purpose: To investigate the association of low renal function and overweight with poor periodontal condition in community-dwelling older Japanese women.

Materials and methods: In total, 359 older women (age range: 55-74 years) participated in this study. Two periodontal parameters - the number of teeth with a probing pocket depth (PPD) or clinical attachment level (CAL) ≥ 4 mm - were used as the dependent variables. The principal independent variables were low renal function as defined by the estimated glomerular filtration rate (eGFR) and overweight as defined by the body mass index. Poisson regression analysis was used to calculate the ratio of means (RM).

Results: The RMs of the number of teeth with a PPD or CAL ≥ 4 mm in an adjusted model without an interaction term were 1.21- or 1.27-fold higher among those with an eGFR < 60, while those among the participants with an eGFR < 60 in the adjusted model with interaction terms for the number of teeth with a PPD or CAL ≥ 4 mm were 1.43- or 1.36-fold higher. In addition, increments of periodontal risk with low renal function and overweight showed a slightly smaller to negative trend.

Conclusion: The present findings suggest a connection between unfavourable periodontal health and both renal function and being overweight among older Japanese women. A weak negative interaction was also found between poor renal condition and overweight in relation to periodontal condition.