Perspectives on spatiotemporal and kinematic gait alterations and intrinsic capacity in Chinese older adults: An analysis of cross-sectional study by latent class analysis

Intrinsic capacity (IC), a multidimensional measure of physical and mental function proposed by the World Health Organization (WHO), may help identify older adults at risk of falls. However, it remains unclear how different patterns of IC decline relate to changes in walking ability. This cross-sectional study enrolled 833 adults aged 60 years or older in Beijing, China, aiming to identify distinct IC subgroups and examine differences in gait characteristics across these subgroups. WHO-recommended assessment tools and wearable sensor-based gait analysis during 12-meter walking trials were used. Latent class analysis identified three IC subgroups: "relatively healthy" (54.5%), "sensorimotor decline" (37.7%), and "extensively impaired" (7.8%). Compared to the "relatively healthy" group, both the "sensorimotor decline" and "extensively impaired" groups showed significantly worse walking performance, including reduced cadence, shorter stride length, lower ground impact, and poorer footfall control, with greater impairments observed in the "extensively impaired" group. In addition, the "extensively impaired" group showed greater stride length variability, while the "sensorimotor decline" group showed greater asymmetry across most gait parameters. These findings were confirmed by sensitivity analyses. IC subgroup classification can effectively identify older adults with distinct fall risk profiles. Sensorimotor training is recommended for the "sensorimotor decline" group, while multidisciplinary rehabilitation is recommended for the "extensively impaired" group. IC assessment offers a simple and cost-effective approach to fall risk screening in clinical and community settings.