Maximum occlusal force and physical performance in the oldest old: the Tokyo oldest old survey on total health.
OBJECTIVE
To elucidate the independent relationship between masticatory and physical performance in community-living oldest old people (mean age ± standard deviation 87.8 ± 2.2, range 85-102).


METHODS
Cross-sectional analysis.


METHODS
University research center or home-based examination.


METHODS
Four hundred eighty-nine community-living individuals (219 men, 270 women) aged 85 and older.


METHODS
Maximum occlusal force (MOF) was measured using an occlusal force measuring device. Sociodemographic and functional factors, oral health, comorbidities, blood chemistry, lower extremity performance, and handgrip strength were assessed. Blood chemistry analyses included serum albumin, C-reactive protein, interleukin (IL)-6, and total and free testosterone.


RESULTS
MOF was significantly associated with age, body mass index, and cognitive impairment in men but not in women. Comorbidities and blood chemistry were not associated with MOF except for a significant association with IL-6 concentration in women. In a multivariate model adjusted for various confounders, lower MOF was associated with greater risk for poor performance on the timed up and go (TUG) test in men and women (men: odds ratio (OR)=2.34, 95% confidence interval (CI)=1.02-5.38; women: OR=2.44, 95% CI=1.12-5.33). MOF was similarly associated with performance in chair standing, one-leg standing, and handgrip strength only in men. These associations remained after adjustment for number of natural teeth.


CONCLUSIONS
MOF was strongly and independently associated with all measures of physical performance in men and with the TUG test in women after adjustment for various confounders, suggesting that age-related declines in masticatory and skeletal muscle functions share common mechanistic pathways in older age, particularly in men.
Department of Complete Denture Prosthodontics, School of Dentistry, Nihon University,1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan. iinuma@dent.nihon-u.ac.jp
Toshimitsu
T
Iinuma
Yasumichi
Y
Arai
Motoko
M
Fukumoto
Michiyo
M
Takayama
Yukiko
Y
Abe
Keiko
K
Asakura
Yuji
Y
Nishiwaki
Toru
T
Takebayashi
Takashi
T
Iwase
Kazuo
K
Komiyama
Nobuhito
N
Gionhaku
Nobuyoshi
N
Hirose
D000203:Activities of Daily Living; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001732:Bite Force; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D015577:Geriatric Assessment / Q000379:methods*; D018737:Hand Strength / Q000502:physiology; D006304:Health Status; D006801:Humans; D008297:Male; D008410:Masticatory Muscles / Q000502:physiology*; D011159:Population Surveillance; D012189:Retrospective Studies; D014041:Tokyo; D014505:Urban Population