Subjective masticatory function and healthy life expectancy among older adults in Singapore: a multistate life table analysis

AIM: Masticatory function may influence physical capacity and independence in older age. This study estimated total life expectancy (LE) and healthy LE (defined as years free of self- or proxy-reported limitations in activities of daily living (ADL) or in physical function) by masticatory function status among older adults, aged 60 and above. MATERIALS AND METHODS: Using three waves of data (2009-2015) on 3381 participants of a nationally representative survey of older Singapore citizens and permanent residents, inverse probability weighted-multistate life table models estimated total and healthy LE, stratified by self- or proxy-reported masticatory function and dental prostheses use. RESULTS: Impaired masticatory function was associated with shorter total and ADL-free LE, with greater reductions among dental prostheses users. At age 60, individuals without masticatory impairment lived 2.9 more ADL-free years than those with masticatory impairment (18.0 years [95 % CI 17.1-18.9] vs 15.1 years [95 % CI 13.9-16.3]); this gap narrowed to 1.7 years at age 80. Individuals with masticatory impairment spent 6-12 % higher proportion of remaining life with ADL limitations. Dental prostheses improved healthy LE overall but gains in ADL-free years were greater for individuals without masticatory impairment. For physical function-based healthy LE, masticatory impairment was associated with reductions of 0.9-2.2 years among non-users and 0.6-1.1 years among prostheses users. CONCLUSION: Masticatory function is a determinant of healthy ageing. Dental prostheses provide partial compensation in healthy LE when masticatory function is impaired among older adults. CLINICAL SIGNIFICANCE: Geriatric care should integrate oral functional screening with objective assessments of mastication where feasible and prioritize function-oriented rehabilitation to extend healthy LE.