Trends in Incidence of Disability in Activities of Daily Living in Chinese Older Adults: 1993-2006

Objectives: To investigate time trends in incidence of activity of daily living (ADL) disability of Chinese older adults and to explore factors potentially contributing to trends.

Design: Population-based prospective study using a multistage, randomized, cluster sampling process.

Setting: Nine provinces of China.

Participants: Three consecutive cohorts of people aged 60 and older from the China Health and Nutrition Survey: cohort 1993-2000 (n = 831), cohort 1997-2004 (n = 1,091), cohort 2000-2006 (n = 1,152).

Measurements: Disability in ADLs was defined as inability to perform at least one of five self-care activities (transferring, dressing, toileting, bathing, feeding). Data were analyzed using Cox and generalized estimating equation models.

Results: The incidence (per 1,000 person-years) of ADL disability decreased significantly from 35.3 in 1993-2000 and 28.9 in 1997-2004 to 24.3 in 2000-2006 in Chinese older adults (P_trend < .001). The incidence of ADL disability decreased significantly in men and women, in young-old adults (aged 60-74), and in those living in rural areas (all P_trend ≤ .02) after controlling for multiple potential influential factors. Of the five ADL items, decline in incidence of disability was significant in transferring (P_trend < .001) and bathing (P_trend = .002) and marginally significant in toileting (P_trend = .06) but stable in dressing (P_trend = .38) and feeding (P_trend = .26).

Conclusion: The incidence of ADL disability decreased from 1993 to 2006 in older adults in China, especially in transferring and bathing, independent of sociodemographic, lifestyle, and chronic health conditions.