Intrinsic capacity impairments are associated with increased risk of incident dementia among community-dwelling older adults: Results from a 9-year follow-up of a nationwide cohort in Taiwan

OBJECTIVES: The main aim of this study was to examine whether screening for intrinsic capacity (IC) impairments could identify those at increased risk of incidence of dementia among community-dwelling older adults. DESIGN: Nine-year longitudinal study. SETTINGS AND PARTICIPANTS: A total of 2308 community-dwelling persons aged 65 years or older who participated in the National Health Interview Survey (NHIS) in Taiwan, 2013. MEASUREMENTS: IC impairments were measured using the questionnaire from NHIS based on six domains of cognition, vitality, locomotion, vision, hearing, and psychological. The incidence of dementia was confirmed by the computerized data files of the Taiwan National Health Insurance claims database. RESULTS: In this study, a total of 358 persons developed incident dementia during the 9-year follow-up, giving a cumulative incidence rate of 15.5% (358/2308). Overall, 28.4% of participants had one IC domain impairment, 29.4% of participants had two or more domains impairment. Compared to those participants with no IC impairment, participants with one IC domain impairment had no increased risk of incident dementia (adjusted SHR=1.17; 95% CI=0.89-1.54), but increased risk was observed in participants with impairments in two or more domains (adjusted SHR=1.54; 95% CI=1.18-2.01). CONCLUSIONS: Our results highlight the high prevalence of participants with impairments in two or more IC domains and its independent association with increased risk of incident dementia among community-dwelling older adults. Further investigation is needed to explore whether such individuals could benefit from interventions to reduce risk of dementia.