Trajectories of Intrinsic Capacity: Determinants and Associations with Disability

Area of Science:

• Gerontology
• Public Health
• Biostatistics

Background:

• Intrinsic capacity (IC) declines with age, increasing disability risk.
• Limited understanding of how IC decline patterns relate to disability.
• Need to identify distinct IC trajectories in older populations.

Purpose of the Study:

• Identify different intrinsic capacity (IC) trajectories in older adults.
• Examine determinants of these IC trajectories.
• Assess associations between IC trajectories and Instrumental Activities of Daily Living (IADL) disability.

Main Methods:

• Longitudinal cohort study of 1371 community-dwelling older adults (aged 60+).
• Bi-factor model used for IC score generation across four time points.
• Latent class growth analysis identified IC trajectories; logistic regression examined IADL association.

Main Results:

• Three distinct IC trajectories identified: high/least declining, and low/most declining.
• Older age, female gender, lower financial adequacy, public housing, and chronic diseases linked to the most declining IC trajectory.
• The highest IC trajectory group showed significantly preserved IADL (OR 3.179) compared to the middle group, while the lowest trajectory group had impaired IADL (OR 0.253).

Conclusions:

• Distinct IC trajectories exist in older adults.
• Monitoring IC trajectories is clinically relevant for preserving functional ability.
• Focus should shift towards proactive management of IC to prevent disability.