Care dependence and activities of daily living in relation to ageing: results of a longitudinal study.

From 1990 to 1993, the University of Limburg and the Pepijn Centre, the Netherlands, have performed a prospective cohort study on ageing and intellectual disability. The key questions of the study were: "To what degree do the level of care dependence and activities of daily living (ADL) differ between age groups, and to what degree do these skills change during the study period (3 years)? Are the changes age related?'. Looking at the changes in time, the results show that the level of care dependence did not change substantially in the sample of 1602 residents of Dutch facilities for people with intellectual disability. Only the oldest residents (70+ years) showed a significant decline in independence. The results also show that the skills of young people with Down's syndrome (< 40 years) did not change substantially, whereas older people with Down's syndrome (40+ years) showed a substantial decrease in ADL-skills. The ADL-skills of the residents with other aetiological diagnoses younger than 60 years of age did not change substantially, while the older residents (60-69 and 70+ years) showed a significant decrease in ADL-functions. The trend between changes in ADL and age in both aetiological groups was statistically significant. Attention is paid to the implications of these findings in the discussion.