Abstract
Objectives
It is inconsistent in the literature on whether inequalities of health in older age
widen or narrow over time. We assessed the associations of socioeconomic status (SES),
physical functioning, and mortality in an older age cohort in Hong Kong.
Design
Longitudinal cohort study.
Setting and Participants
We recruited 2032 older adults aged 70+ in 1991 to 1992 and followed them for 10 years.
Methods
SES was operationalized as education, baseline individual income, and longest-held
occupation in lifetime. Physical functioning was measured by Barthel's Index for activities
of daily living (ADL), from which disability was defined as ADL score <20. Mortality
data were obtained from the Death Registry. Bayesian joint modeling with 2 sub-models,
mixed-effect, and Cox proportional hazard model, were used to respectively model the
associations of SES and disability, and SES and mortality, accounting for selection
by mortality.
Results
Education and income at baseline were not clearly related to disability, but those
with lower education level and income at baseline tended to have their risks increased
with time. Older adults who had been mostly economically inactive or unemployed in
their lifetime had higher risk of disability [odds ratio 3.24; 95% credible interval
(95%CrI) 1.29 to 7.97], and such risk increased over time. For mortality, older adults
with no schooling were at higher risk compared with those with secondary education
or above (hazard ratio 1.25; 95%CrI 1.00 to 1.57). Income at baseline and longest-held
occupation in lifetime were not clearly related to mortality.
Conclusions and Implications
We observed inequalities of health of older adults in Hong Kong that widened as they
age. Community and medical interventions targeting the older adults with the lowest
SES would be important to prevent their more rapid decline in physical functioning.
Keywords
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Article info
Publication history
Published online: September 20, 2021
Footnotes
The study was supported by the Croucher Foundation and the Hong Kong Health Services Research Grant #411009. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
The authors declare no conflicts of interest.
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© 2021 AMDA - The Society for Post-Acute and Long-Term Care Medicine.
