Multivariate analysis of independent determinants of ADL/IADL and quality of life in the elderly

BACKGROUND: This study evaluated the determinants of disability and quality of life in elderly people who participated at the multi-centred RubiN project (Regional ununterbrochen betreut im Netz) in Germany. METHODS: Baseline data of the subjects aged 70 years and older of the RubiN project were used and only subjects with complete data sets were considered for the ensuing analysis (complete case analysis (CCA)). Disability was examined using the concepts of ADL (activities of daily living) and IADL (instrumental activities of daily living). Subjects exhibiting one or more deficiencies in ADL respectively IADL were considered as ADL respectively IADL disabled. Quality of life was assessed using the WHOQOL-BREF and the WHOQOL-OLD. Applying multivariate analysis, sociodemographic factors, psychosocial characteristics as well as the functional, nutritional and cognitive status were explored as potential determinants of disability and quality of life in the elderly. RESULTS: One thousand three hundred seventy-five subjects from the RubiN project exhibited data completeness regarding baseline data. ADL and IADL disability were both associated with the respective other construct of disability, sex, a reduced cognitive and functional status as well as domains of the WHOQOL-BREF. Furthermore, ADL disability was related to social participation, while IADL disability was linked to age, education and social support. Sex, ADL and IADL disability, income, social support and social participation as well as the functional status were predictors of the domain ‘Physical Health’ (WHOQOL-BREF). The facet ‘Social Participation’ (WHOQOL-OLD) was affected by both ADL and IADL disability, income, social participation, the nutritional and also the functional status. CONCLUSIONS: Several potential determinants of disability and quality of life were identified and confirmed in this study. Attention should be drawn to prevention schemes as many of these determinants appear to be at least partly modifiable. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12877-022-03621-3.