Declined intrinsic capacity and its influencing factors among older adults in China: a national cross-sectional survey

Abstract Background The decline in intrinsic capacity (IC) among older adults is a significant global health challenge, impacting their well-being and quality of life. Despite global efforts to promote healthy aging, research on factors contributing to IC decline in the Chinese population is limited. This study aims to investigate the decline of intrinsic capacity in Chinese older adults and to explore the influence of sociodemographic, health status, and lifestyle factors on the decline of intrinsic capacity. Methods Prevalence of intrinsic capacity decline was described using frequency analysis, while chi-square tests were used to analyze its associations with sociodemographic characteristics, health status, and lifestyle factors. Binary logistic regression analysis was used to identify significant factors influencing the decline of intrinsic capacity (α = 0.05). Results Among 6,941 respondents aged 60 years and above, 83.8% reported a decline in intrinsic capacity. Cognitive impairment was predominant (71.8%), followed by psychological (40.4%), locomotion (19.8%), vitality (17.2%), and sensory impairments (8.9%). Sociodemographic factors associated with a decline in intrinsic capacity included female gender, age 80 and older, unmarried, divorced or widowed status, rural residence, low education, and lack of health or pension insurance (p < 0.05). From the perspective of health status, factors associated with higher rates of intrinsic capacity decline include poor self-rated health, multiple chronic conditions, recent falls, frequent physical pain, recent outpatient visits, hospitalizations, and pessimistic life expectancy (p < 0.05). Lifestyle factors such as alcohol consumption, lack of social participation, prolonged sleep duration, and no Internet use were also linked to higher rates of intrinsic capacity decline (p < 0.05). The results of the binary logistic regression indicated that age, marital status, residence address, education level, pension insurance status, self-rated health, the presence of multiple chronic conditions, frequency of perceived physical pain, subjective life expectancy, social participation, sleep duration, and Internet access significantly influenced the decline of intrinsic capacity in older adults (p < 0.05). Conclusions The decline in intrinsic capacity among older adults in China, particularly in cognitive impairment, is concerning. Targeted interventions are necessary for vulnerable populations, especially those who are older, divorced or widowed, living in rural areas, or have lower education levels. Enhancing social pensions, promoting social participation, encouraging healthy sleep patterns, and improving digital inclusion to improve intrinsic capacity among older adults is important.