Multiple roads to success: A latent class analysis on successful aging among Hong Kong near-centenarians and centenarians (NCC)

Abstract

Notwithstanding successful aging being a multidimensional construct, measuring successful aging in adults of advanced age, such as nonagenarians and centenarians, has often been challenging. First, over reliance on physical health criteria could be unrealistic, considering most of these older adults are living with multimorbidity and disability. Second, enumerating the number of criteria fulfilled may not reflect the diversity of how they attain (partial) successful aging through soliciting different resources in their daily lives. Hence, this study investigated the subphenotypes of successful aging using the data from Hong Kong Centenarian Study 2 by referencing to two models which have been adopted in previous centenarian studies.

Method: Between April 2021 and September 2022, we interviewed the family caregivers of 146 community dwelling older adults aged 95 or above by phone. A structured questionnaire with items on the physical, psychological, and social well-being of the older adults was administered. Latent class analysis was used to identify the classes of successful aging based on eleven dichotomized indicators - good health, happiness, good perceived economic status, absence of dementia diagnosis, ambulation, resistance, indoor transfer, dressing, vision and hearing impairment and weekly social activities.

Results: Among the 146 older adults aged between 95 to 106 (mean (SD): 97.5 (2.5); 76.0% female), 13.0% fulfilled all successful aging criteria based on caregivers’ judgments of happiness, health, and economic status, and 2.1% fulfilled all criteria based on caregivers’ observation of their physical functions and social activities. LCA identified three latent classes: Class 1 (46.6%) characterized by poor cognitive and functional health, Class 2 (37.0%) with good functional health but poor mobility, and Class 3 (16.4%) with overall good health. Class membership was unrelated to gender, age, living arrangement, and education status of the older adults.

Conclusions:

Notwithstanding the oldest-old cohort being the fastest-growing population in most ageing societies, characterizing successful ageing in adults of advanced age, such as nonagenarians and centenarians, remains challenging. This study investigated the successful ageing subphenotypes using the data from Hong Kong Centenarian Study 2. Between April 2021 and September 2022, 146 family caregivers of community-dwelling older adults aged 95 or above were interviewed by phone. Latent class analysis identified three classes—Overall Frail (46.6%) with poor mobility, cognitive and functional health, Nonambulant (37.0%) but good functional health, and Robust (16.4%) with overall good health—from 11 indicators based on caregivers’ reports. Although we found a low prevalence of fulfillment of all indicators of successful ageing, our findings will help care professionals appreciate the heterogeneity underlying partial successful ageing in this vulnerable cohort for segmented and targeted healthy longevity interventions.