Association between sedentary time and intrinsic capacity among community-dwelling older adults: evidence from a prospective BLINDSCE cohort.

Abstract

While existing studies have linked declines in intrinsic capacity (IC) to adverse health outcomes, the role of potentially modifiable lifestyle factors in this pathway, especially sedentary behavior, remains critically underexplored. Using data from the Beijing Longitudinal Disability Survey in Community Elderly (BLINDSCE) cohort (2023-2024), this study investigated both cross-sectional and 1-year longitudinal associations between sedentary time and IC in community-dwelling older adults. Of the 2044 participants (≥ 65 years) enrolled at baseline, 1576 completed 1-year follow-up assessments through face-to-face interviews. Multivariable linear regression analyses revealed that each additional hour of daily sedentary time was associated with a 1.18-point lower baseline IC score (95% CI: -1.38, -0.98) and an accelerated 0.48-point greater IC decline over 1 year (95% CI: -0.72, -0.24). Exposure-response analyses showed a linear relationship between sedentary time and 1-year IC change. Significant interaction effects were observed between sedentary time and baseline IC level, moderate-to-vigorous physical activity (MVPA), and daily internet use. These findings provide empirical support for reducing sedentary behavior, ensuring adequate MVPA, promoting moderate digital engagement, and implementing IC-stratified interventions to promote healthy aging-thereby operationalizing the WHO Integrated Care for Older People (ICOPE) framework through actionable public health measures.