International comparison of oral hypofunction among community-dwelling older adults in three Asian countries: A cross-sectional and multi-national study

Authors

• Ryosuke Yanagida, Department of Dysphagia Rehabilitation, Graduate Schools of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, JapanFollow
• Kohei Yamaguchi, Department of Dysphagia Rehabilitation, Graduate Schools of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, Japan
• Kazuharu Nakagawa, Department of Dysphagia Rehabilitation, Graduate Schools of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, Japan
• Chantaramanee Ariya, Department of Dysphagia Rehabilitation, Graduate Schools of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, Japan
• Patcharaphol Samnieng, Department of Oral Prevention, Faculty of Dentistry, Naresuan University, Phitsanulok, Thailand
• Megan F Liu, School of Gerontology and Long-Term Care, College of Nursing, Taipei Medical University, Taipei, Taiwan
• Nai-Chia Teng, School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
• Ting-Yi Renn, School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
• Rieko Moritoyo, Department of Dysphagia Rehabilitation, Graduate Schools of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, Japan
• Sirinthip Amornsuradech, Department of Dysphagia Rehabilitation, Graduate Schools of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, Japan
• Kanako Yoshimi, Department of Dysphagia Rehabilitation, Graduate Schools of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, Japan
• Haruka Tohara, Department of Dysphagia Rehabilitation, Graduate Schools of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, Japan

Abstract

Background/purpose: In aging Asian societies, oral hypofunction among older adults has gained importance, with most epidemiological studies conducted in Japan. We aimed to compare oral function in community-dwelling older adults in Japan, Taiwan, and Thailand.

Materials and methods: Community-dwelling older adults aged ≥ 60 years who participated in Yokohama, Taipei, and Phitsanulok health surveys (May 2022–September 2024) were included. Age, sex, body mass index (BMI), and denture use data were recorded. Using the Japanese Society of Gerodontology diagnostic framework, seven oral hypofunction components were evaluated: oral hygiene, oral dryness, occlusal force, tongue–lip motor function, tongue pressure, masticatory function, and swallowing function. Between-site differences were examined using chi-square tests, one-way analysis of variance, and a Kruskal–Wallis test. Exploratory sensitivity analysis excluding the oral diadochokinesis criterion and multivariable logistic regression adjusted for age, sex, BMI, and denture use were conducted.

Results: Significant differences were observed among 179 participants in the 3 study sites concerning all oral function criteria, except oral dryness. Oral hypofunction prevalence was 41.1 %, 83.1 %, and 56.3 %, in Yokohama, Taipei, and Phitsanulok, respectively. After adjusting for age, sex, BMI, and denture use, participants in Taipei demonstrated significantly higher odds of oral hypofunction than did those in Yokohama. Participants in Phitsanulok demonstrated higher odds; however, it did not reach significance.

Conclusion: Oral hypofunction was common among the participants across the three Asian study sites, whereas prevalence and component profiles differed. Larger, multi-region studies and locally appropriate reference values are needed to enable valid cross-site and cross-country comparisons.

Recommended Citation

Yanagida, Ryosuke; Yamaguchi, Kohei; Nakagawa, Kazuharu; Ariya, Chantaramanee; Samnieng, Patcharaphol; Liu, Megan F; Teng, Nai-Chia; Renn, Ting-Yi; Moritoyo, Rieko; Amornsuradech, Sirinthip; Yoshimi, Kanako; and Tohara, Haruka (2026) "International comparison of oral hypofunction among community-dwelling older adults in three Asian countries: A cross-sectional and multi-national study," Journal of Dental Sciences: Vol. 21: Iss. 4, Article 8.
Available at: https://jds.ads.org.tw/journal/vol21/iss4/8

Publication Date

2026

Received Date

July 14 2026

Accepted Date

July 21 2026

Final Revision Date

July 21 2026