Research Paper|Volume 15, Issue 3|pp 748—764

Intrinsic capacity differs from functional ability in predicting 10-year mortality and biological features in healthy aging: results from the I-Lan longitudinal aging study

Wei-Ju Lee^1,^2,³, Li-Ning Peng^1,^2,⁴, Ming-Hsien Lin^1,^2,⁴, Ching-Hui Loh^1,^2,⁵, Fei-Yuan Hsiao^6,^7,⁸, Liang-Kung Chen^1,^2,^4,⁹

¹Center for Healthy Longevity and Aging Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
²Department of Geriatric Medicine, National Yang Ming Chiao Tung University, School of Medicine, Taipei, Taiwan
³Department of Family Medicine, Taipei Veterans General Hospital Yuanshan Branch, Yi-Lan County, Taiwan
⁴Center for Geriatrics and Gerontology, Taipei Veterans General Hospital, Taipei, Taiwan
⁵Center of Health and Aging, Hualien Tzu Chi Hospital Buddhist Tzu Chi Medical Foundation, Hualien County, Taiwan
⁶Graduate Institute of Clinical Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan
⁷School of Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan
⁸Department of Pharmacy, National Taiwan University Hospital, Taipei, Taiwan
⁹Taipei Municipal Gan-Dau Hospital, Taipei, Taiwan

Received: July 28, 2022Accepted: January 23, 2023Published: February 6, 2023

https://doi.org/10.18632/aging.204508

Copyright: © 2023 Lee et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

This study aimed to explore the biological features and mortality risk of intrinsic capacity (IC) and functional ability (FA). Based on data from 1839 participants from the I-Lan Longitudinal Aging Study, multivariable Cox proportional hazard models were used to evaluate the predictive ability of IC (range 0–100) and FA (range 0–100) on 10-year mortality. Of 2038 repeated measurements for IC within a 7-year observational period, multivariable logistic regression was used to compare biological features of participants with maintained, improved and rapidly deteriorated IC. A 1-point increased IC value was associated with a 5% (HR 0.95, 95% CI 0.93–0.97, p < 0.001) decrease in mortality risk. Low IC (HR 1.94, 95% CI 1.39–2.70, p < 0.001) was associated with higher mortality risk. Hyperglycemia (OR 1.40, 95% CI 1.09–1.81, p = 0.010), low serum levels of DHEA-S (OR 3.33, 95% CI 1.32–8.41, p = 0.011), and high serum levels of C-reactive protein (OR 1.45, 95% CI 1.05–2.00, p = 0.023) were associated with low IC at baseline. Low serum levels of DHEA-S (middle tertile OR 1.84, 95% CI 1.15–2.95, p = 0.012; lowest tertile OR 2.25, 95% CI 1.34–3.77, p = 0.002) and vitamin D deficiency (OR 1.82, 95% CI 1.02–3.27, p = 0.044) were associated with rapid deterioration of IC. IC and FA predicted 10-year mortality, whereas chronic inflammation, hyperglycemia, and low DHEA-S were associated with low IC status. Low DHEA-S and vitamin D deficiency may be considered as potential biomarkers of rapid IC declines, which implies underlying biological mechanisms of healthy aging.