Abstract
The decline in activities of daily living (ADL) significantly impacts independence and quality of life among older adults. This study used data from the China Health and Retirement Longitudinal Study (CHARLS) to conduct a cross-sectional analysis of 4,751 functionally impaired older Chinese adults aged ≥ 60 years with Modified Barthel Index (MBI) scores < 100. Participants were stratified into seven age groups (60-64, 65-69, 70-74, 75-79, 80-84, 85-89, and ≥ 90 years), and simple linear models were used to analyze age-related differences across 12 ADL domains. Results revealed three patterns of functional decline: (1) basic self-care activities (eating, getting up) remained relatively stable across age groups; (2) mobility functions (walking, stair climbing) showed progressive decline, with walking demonstrating continuous deterioration across multiple age transitions; and (3) personal care activities (bathing, grooming, toileting, dressing) showed significant decline primarily between ages 75-84. Gender-stratified analysis identified female advantages in self-care abilities and age-related changes in walking performance. The 75-84 years period emerged as a critical transition, with six functional domains showing significant deterioration. These findings suggest that interventions targeting mobility preservation and targeted interventions during the late 70s to early 80s may help delay functional decline and maintain independence in older adults.