Association Between Tooth Loss, Receipt of Dental Care, and Functional Disability in an Elderly Japanese Population: The Tsurugaya Project

Takamasa Komiyama; Takashi Ohi; Yoshitada Miyoshi; Takahisa Murakami; Akito Tsuboi; Yasutake Tomata; Ichiro Tsuji; Makoto Watanabe; Yoshinori Hattori

doi:10.1111/jgs.14390

Association Between Tooth Loss, Receipt of Dental Care, and Functional Disability in an Elderly Japanese Population: The Tsurugaya Project

J Am Geriatr Soc. 2016 Dec;64(12):2495-2502. doi: 10.1111/jgs.14390. Epub 2016 Nov 1.

Authors

Takamasa Komiyama¹, Takashi Ohi^{1

2}, Yoshitada Miyoshi¹, Takahisa Murakami³, Akito Tsuboi⁴, Yasutake Tomata⁵, Ichiro Tsuji⁵, Makoto Watanabe⁶, Yoshinori Hattori¹

Affiliations

¹ Division of Aging and Geriatric Dentistry, Department of Oral Function and Morphology, Graduate School of Dentistry, Sendai, Japan.
² Japanese Red Cross Ishinomaki Hospital, Ishinomaki, Japan.
³ Division of Public Health, Hygiene, and Epidemiology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Japan.
⁴ Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan.
⁵ Division of Epidemiology, Department of Health Informatics and Public Health, School of Public Health, Graduate School of Medicine, Tohoku University, Sendai, Japan.
⁶ Department of Social Welfare, Faculty of General Welfare, Tohoku Fukushi University, Sendai, Japan.

PMID: 27801931
DOI: 10.1111/jgs.14390

Abstract

Objectives: To examine whether number of remaining teeth and regular dental care affect incident functional disability in elderly Japanese adults.

Design: Prospective cohort study.

Setting: Tsurugaya district, Sendai, Japan.

Participants: Community-dwelling individuals aged 70 and older (N = 834).

Measurements: The outcome measurement was incident functional disability, defined as first certification of long-term care insurance in Japan, which is determined on the basis of a strictly established uniform nationwide standard. During a median follow-up of 7.9 years (interquartile range 4.8-7.9 years), information on long-term care insurance was obtained from the Sendai Municipal Authority. Oral health was assessed according to number of remaining teeth and presence or absence of regular dental care. Data were also collected on age, sex, body mass index, medical history, smoking, alcohol consumption, duration of education, depressive symptoms, cognitive impairment, physical functioning, and social support.

Results: Participants with 10 to 19 teeth (adjusted hazard ratio (aHR) = 1.42, 95% confidence interval (CI) = 1.03-1.94), one to nine teeth (aHR = 1.46, 95% CI = 1.04-2.03), and no teeth (aHR = 1.49, 95% CI = 1.03-2.14) were more likely to develop functional disability than those with 20 or more teeth. There was no significant difference in risk of functional disability between participants with 20 or more teeth and those with zero to 19 teeth who were receiving regular dental care, whereas those with zero to 19 teeth without regular dental care had a significantly greater risk of functional disability than those with 20 or more teeth (HR = 1.46, 95% CI = 1.11-1.92).

Conclusion: Tooth loss was associated with greater risk of functional disability in community-dwelling elderly Japanese. Regular dental care might moderate the risk of functional disability in elderly individuals with missing teeth.

Keywords: cohort study; dental care; disability; geriatrics; tooth loss.

MeSH terms

Aged
Dental Care for Aged / statistics & numerical data*
Disability Evaluation*
Female
Geriatric Assessment*
Humans
Incidence
Insurance, Long-Term Care
Japan / epidemiology
Male
Oral Health
Prospective Studies
Risk Factors
Tooth Loss / epidemiology*