Morbidity, comorbidity, and their association with disability among community-dwelling oldest-old in Israel

Background. The impact of chronic conditions on the development of disability has not yet been comprehensively studied among the elderly population living in Israel. This study evaluates the prevalence of disability and morbidity among the community-dwelling oldest-old population and examines the association between medical conditions, comorbidity, and disability in basic and instrumental activities of daily living (ADLs, IADLs). Method. The data are based on a national random stratified sample of 1,820 Israeli Jewish individuals 75-94 years old. of whom 1,487 lived in the community. Results. Nineteen percent of the population was disabled in ADLs and 36% in IADLs. Disability rose with age and was higher for women and among individuals of Middle Eastern and North African origin. Stepwise logistic regression indicates that the variables associated with disability in ADLs and IADLs were older age, Middle Eastern or North African origin, living with others, and the following conditions: stroke, hip fracture, diabetes, osteoporosis, anemia, and heart attack. In addition, lower education and suffering from urinary or kidney diseases, respiratory disease, and/or Parkinson's disease were related to disability in ADLs; being a woman and suffering from heart diseases other than heart attack were related to disability in IADLs. Comorbidity was related to increased disability only for individuals with three or more conditions. Conclusions. The identification of medical conditions and sociodemographic variables related to limitations in functioning may serve as a basis for health promotion and disease prevention in elders by attempting to reduce the incidence and disabling consequences of known disabling conditions.