Associations of ADL and IADL disability with physical and mental dimensions of quality of life in people aged 75 years and older.

Background: Quality of life is an important health outcome for older persons. It predicts the adverse outcomes of institutionalization and premature death. The aim of this cross-sectional study was to determine the influence of both disability in activities of daily living (ADL) and instrumental activities of daily living (IADL) on physical and mental dimensions of quality of life.

Methods: A total of 377 Dutch people aged 75 years and older completed a web-based questionnaire. This questionnaire contained the Groningen Activity Restriction Scale (GARS) for measuring ADL and IADL and the Short-Form Health Survey (SF-12) for measuring quality of life. The SF-12 distinguishes two dimensions of quality of life, a physical and mental dimension.

Results: All ADL disability items combined and all IADL disability items combined explained a significant part of the variance of the physical and the mental dimension of quality of life. Only ADL item "stand up from sitting in a chair", and IADL items "do "heavy" household activities" and "do the shopping" were negatively associated with both quality of life dimensions after controlling for all the variables in the model.

Discussion: This study showed that disability in ADL and IADL is negatively associated with quality of life in older people. Therefore, it is important for health care professionals to carry out interventions aimed to prevent and diminish disability or the adverse outcomes of disability such as a lower quality of life. In order to be effective these interventions should be inexpensive, feasible, and easy to implement.