Remaining Tooth Numbers and Falls in the Community-Dwelling Japanese Elderly

Objectives: To assess the relationship between remaining tooth numbers and incidences of falls in two prospective years
Methods: The participants of this 2-year longitudinal study were 124 Japanese older people (42 males and 82 females, average age 81.3 years). At baseline in 2017, dental and physical fitness examinations, including Timed Up & Go test (TUG), walking speed, handgrip strength, were conducted. Mini-Mental State Examination (MMSE) and the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) were also used to assess cognitive function and higher-level functional capacity, respectively. At follow-ups in 2018 and 2019, we ascertained the history of falls by questionnaires. We divided dental status into three groups: (I) subjects with at least 20 remaining teeth, (II) subjects with less than 20 remaining teeth, (III) edentulous subjects. In the multiple logistic regression models, dependent variables are a history of falls at a 1-year follow-up, and a history of falls throughout the study period, while an independent variable is dental status (group I-III). Confounders are age, gender, TUG, walking speed, handgrip strength, MMSE, and TMIG-IC. A significant level was set at 0.05.
Results: Twenty participants (16.1%) reported falls during the first year of follow-up. Seven participants (5.6%) reported falls every year (2017 and 2018). Multiple logistic regression analyses, adjusted for all covariates, show that subjects with less than 20 remaining teeth (group II) have a significantly increased risk of falls at the 1-year follow-up (OR: 4.46, 95% CI: 1.10,18.1), and edentulous subjects (group III) has a significantly increased risk of continuous falls in two consecutive years (OR:16.49, 95% CI: 1.06-256.7) compared with subjects with at least 20 remaining teeth (group I).
Conclusions: The reduced number of teeth may increase the risk of falls, and fall prevention efforts possibly be especially helpful to edentulous older people.