Successful aging among Chinese near-centenarians and centenarians in Hong Kong: a multidimensional and interdisciplinary approach

Abstract

Objectives: This study applied a multidimensional model on a continuum to examine successful aging (SA) and investigated whether SA is associated with biomedical and psychosocial–demographic factors among Hong Kong Chinese near-centenarians and centenarians.

Method: A cross-sectional data analysis was performed on a geographically representative sample of 120 near-centenarians and centenarians with an age range of 95–108 years. We developed an integrated and cumulative Successful Aging Index (SAI) based on participants’ performance in four dimensions: (1) physical and functional health (PF), (2) psychological well-being and cognition (PC), (3) social engagement and family support (SF), (4) economic resources and financial security (EF). To examine the criterion validity of SAI, we conducted a multiple binary logistic regression with interviewer-rated health. A multiple regression model was ran to investigate the independent biomedical and psychosocial–demographic correlates of SAI.

Results: Results show that only 5.8% of participants attained SA in all four dimensions. PF had the least achievers, whereas the proportion was the highest in PC. SAI was significantly associated with interviewer-rated health and a high level of high-density lipoprotein cholesterol. Living with family or friends, high level of optimism, fewer diseases, and barriers to social activities were independent predictors of SAI score.

Conclusion: In the light of the lack of consensus on the constituents and assessment of SA especially among very old adults, our findings add to the extant literature by underscoring the importance of the multidimensional nature and the utility of an integrated and cumulative-based assessment of SA at the extreme of longevity.

Keywords:

• centenarians
• Hong Kong SAR
• successful aging
• healthy longevity
• well-being

Acknowledgements

This study was supported by the Seed Funding Program for Basic Research, the matching fund from the Department of Social Work and Social Administration at University of Hong Kong (Project No. 104001032), and AXA funded red packets to the participants upon the completion of the interview. The authors would like to thank Mr Kenneth Liang, Institute of Human Performance and Prof. Paul Yip, Dr Paul Wong, Ms Noel Chun-Fong Kwok, The Department of Social Work and Social Administration at HKU. Our heartfelt appreciation also goes to Dr Yee-Man Angela Leung, School of Nursing at HKU for the blood test coordination and Dr Morris Tai, Dr Jason So, Queen Mary Hospital, Dr Winnie Mok and Dr Felix Chan, TWGHs Fung Yiu King Hospital, Dr Chan Wai-Man, Dr Linda Hui, Dr Sammy Ng, Ms Shelley Chan, Elderly Health Service, the Department of Health and Ms Grace M.Y. Chan and Ms Winter Chan, Hong Kong Council of Social Service. We also thank Mr Wan W-K (Phlebotomist), Ms Karen Cheung C-P, Ms Irene Lau, Ms Rosanna Liu, and Ms Luk F-L (Registered Nurses) for supporting this study. Finally, the project would not have been possible without the keen participation of the participants and their family members. The earlier draft version of this paper has been presented in the VID conference on ‘Determinants of Unusual and Differential Longevity,’ 21–23 November 2012 in Vienna, Austria and the latest versions have been presented in the International Centenarian Consortium annual meetings that were held at Osaka University, 15–18 May 2014 and in Sardinia, 18–20 June 2015. The authors also thank the anonymous reviewers for their constructive comments on this article.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1. Out of the original sample of 153 participants, we have included an analysis on the participants with valid answers on any of the indicators of SAI (N = 120) and excluded (N = 33) in the current study. The breakdowns of missing values cover four participants providing invalid answers on subjective health; one participant on ADL independence; six participants on Geriatric Depression Scale; 13 participants on Mini-Mental State Examination; two participants on frequency of social activities; 10 participants on presence of spousal/children confidant; 14 participants on perceived economic status of household; and nine participants on sufficiency of income. Some participants had missing values overlapped.

2. We also examined the correlations among the 33 biomarkers and the two indicators of physical and functional health (PF) dimension (i.e., good subjective health and ADL independence). It was found that controlling for the effect of age and gender, subjective health was not significantly related to any biomarkers, whereas ADL independence was related to a lower level of platelet (r = −.26, p = .018) and a higher level of albumin (r = .27, p = .014). Previous studies on centenarians revealed that higher albumin level was related to better functional health (Gondo et al., 2006) and higher levels of hemoglobin and albumin had a significant positive effect on subjective health (Cho et al., 2011), while lower platelet count was related to lower risk of cardiovascular events (Gangemi et al., 2004). Since the current study is interested in the correlates of a multidimensional SA construct, the patterns and pathways were not elaborated through which biomarkers including albumin and platelets manifest themselves in physical and functional health per se.

Additional information

Funding

This study was supported by the Seed Funding Program for Basic Research, the matching fund from the Department of Social Work and Social Administration at University of Hong Kong [Project No. 104001032], and AXA funded red packets to the participants upon the completion of the interview.